BudgetLightForum.com - USB Power Device Reviews

Forums:

RD Electronic USB load LD35

Official specifications:

Rated operational voltage: DC 4-25.0V
Max discharging power: 35W
Rated operational current: 0.25-5.00A (when fan don’t work, the minimum constant current is 0.05A )
Fan Speed: Large size intelligent temperature control fan, speed 8000±10%RPM
Constant current resolution:±1% +3 digits
Heat dispatch method: intelligent temperature control fan + All aluminum fan
Working temperature: -10°C ~ 40°C
Adjustable potentiometer: Precision multiloop adjustable potentiometer
Display mode: 4 bit LED tube
Expansion port: Micro USB port, Type-C port

I got it from Aliexpress dealer: RD official store

I got it in the usual styrofoam box (That is RD’s standard packing) together with some other stuff, inside the box it was wrapped in bubble wrap.

At one end is the two buttons, the current adjustment and the display, at the other end is the 3 usb connectors (Micro, A and C), between is the heatsink and fan.

I will take a closer look at the circuit further down.

The SET button is used to change between different readings, here is the current, it will flash when the load is off and be steady when the load is on.

Actual power dissipated by the load.

Input voltage, this is the voltage feed into the load.

Overload conditions will disable the load and show a warning on the display. Here over power protection (OPP) and over voltage protection (OUP)
Holding the SET button down will toggle automatic resume on/off.
Holding the On/Off button down will toggle automatic on when power is connected.

Load testing

Current resolution is 0.01A
Voltage resolution is 0.1V
Power resolution is 0.1W
Internally current is adjusted in 0.01A steps, it is not analog!
Load is rated to handle 30V before being damaged, load shows OUP between 25V and 30V
Current adjustment range is from 0.00A to 5.09A, but supported range is from 0.05A to 4.00A
The load has USB-A, micro usb and USB-C connectors, all in parallel.
USB-C connector will not turn USB-C output on!
Voltage display shows voltage at input, any voltage drop is due to connector and cable resistance.
I got about 0.12V drop for connection and other resistance in usb load at 5A (Current in on A, check on C).
Current change during 60 minutes with 1.4A load at 24.9V is 0.0005A, i.e. 0.4%
Current change during 60 minutes with 5A load at 6.9V is 0.007A, i.e. 1.4%
The adjustment is a multiturn potentiometer and the display will show the selected current.
The fan is audible, but not loud, it starts and stops as required (This is a bit annoying).
Current when off about 17mA for the electronic and display.

Both current and voltage readout has good precision.

Electronic%20load%20RD%20LD35

Due to the power limit of 35W it is not possible to test with high current and high voltage, here I had enabled automatic recovery, i.e. load would turn on when the voltage was low enough. On many of the high current traces the fan was running when I started at the high voltage, but would stop when the load had cooled down.

Electronic%20load%20RD%20LD35%20min.

Here is a trace with adjustment in minimum position and low current traces. The load has an offset of some mA at these low currents.

Electronic%20load%20RD%20LD35%20load%20test

Electronic%20load%20RD%20LD35%20load%20test

I tried two 1 hour test, one at maximum voltage (I used 24.9V and 1.4A) and one at maximum current (I used 6.9V and 5A).

Temp5799

M1: 44.5°C, M2: 49.1°C, HS1: 52.3°C
First set of thermo photos is from 24.9V 1.4A test

Temp5800

M1: 61.0°C, HS1: 66.0°C

Temp5801

M1: 81.1°C, HS1: 91.6°C
Both transistor and regulator warms up with high input voltage.

Temp5796

M1: 44.3°C, M2: 48.3°C, HS1: 53.0°C
Next set of thermo photos is from 6.9V 5A test

Temp5797

HS1: 69.4°C

Temp5798

M1: 97.7°C, HS1: 111.8°C
With lower input voltage the transistor must handle all the power and gets a bit warmer, the shunt resistor do also get warm at 5A

A look at the circuit

The transistor (TIP122) is the load element, it uses a resistor (R6: 0.025ohm) to sense the current. The fan is a 5V version and has its own regulator (LM317), at high input voltage it must handle some power. Turning the fan on/off is handled by a small transistor (Q2), the temperature sensor is very close to the TIP122 transistor and is a NTC (RT1) that is connected to the MPU.
The electronic has its own voltage regulators (U6: M5350B 5V, IC7:5333B 3.3V). The control of the load current is done with some OpAmps (U2 & U7: 358). The brain in the circuit is a 8051 microprocessor (U1: N76E003AT20 18KB Flash, 1k RAM, 12 bit ADC). For the display a 8 bit shift register (74HC595) is used to get more output pins.

Why 4 OpAmp (358 is a dual OpAmp), a load only need one OpAmp. A look at the circuit shows some filters connected to the MPU on U7. One filter is R11, R12, C8 and C9, the other filter is R15, R16, C14 and C15.

0.5Acurve

Filter input from microprocessor at 0.5A

3Acurve

Filter input from microprocessor at 3A

The R15 etc. filter is for fine adjustment and R11 etc. filter is for coarse adjustment.

3Aclamp

The above PWM frequency is 1kHz, is there any trace of it on the output? To test that I used my current clamp to check the load current, there is no trace of the 1kHz PWM frequency.

Conclusion

The load works fine and with the multiturn adjustment and display it is easy to adjust. It has no problems handle the rated 35W power. It is not for low loads, the display and adjustment do not have resolution for it and it also need some minimum current to work.
It is a interesting design choice that the analog current setting is sampled by the microprocessor and then output as two PWM channels that is filtered and mixed, before being feed to the load regulation.
With USB-C I am missing the ability to turn outputs on (It is just a resistor), this will limit its usefulness for USB-C.

Notes

The load was supplied by RD for review.

The company also has a 25W load, main difference is the fan.

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Samsung EP-TA20EWE (Fake)

Official specifications:

Power Capacity: 9V-1.87A 5V-2.0A
Color: White
Voltage: Input:100-240V
Adaptive Fast Rapid Charger: Adaptive Fast Rapid Charger For Samsung

I got it from a ebay dealer: jtao1986

I got it in a envelope, not in a box marked Samsung

Measurements

Power consumption when idle is 0.1 watt
Output is auto coded as DCP and QC2 with 5V and 9V (This may be for Samsung)
Weight: 36.5g
Size: 75.4 × 36.5 × 23.5 mm

Samsung%20EP-TA20EWE%20230V%20load%20sweep

The charger can deliver about 3.2A, this is considerable more than the rated 2A.

Samsung%20EP-TA20EWE%20120V%20load%20sweep

At 120VAC the output drops to 3.1A

Samsung%20EP-TA20EWE%20QC9V%20230V%20load%20sweep

At 9V the charger can deliver 1.8A

Samsung%20EP-TA20EWE%20QC9V%20230V%20load%20test

Running at 9V 1.67A for one hour worked fine.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5783

M1: 72.6°C, M2: 65.4°C, HS1: 80.1°C
HS1 is the transformer.

Temp5784

M1: 76.3°C, M2: 65.7°C, HS1: 77.5°C

Temp5785

M1: 64.8°C, HS1: 77.3°C

Temp5786

HS1: 73.3°C
The diode below the usb connector will heat it up.

Temp5787

M1: 57.3°C, HS1: 79.2°C

10ohm

At 0.5A the noise is 100mV rms and 2622mVpp

5ohm

At 1A the noise is 115mV rms and 2587mVpp

2.5ohm

At 2A the noise is 143mV rms and 3153mVpp

10ohmQC9V

At 0.9A the noise is 169mV rms and 1524mVpp

Tear down

Using my vice to apply some pressure around the top made it pop off.

At the mains input is a fusible resistor (F01) and a inrush current limiter (TM01: NTC) followed by a common mode coil, there is another inductor (L02) between the two mains capacitors. The main switcher transistor (Q01) is next to the transformer and near the plastic shield is the safety capacitor (CY01).
Something is wrong with the output capacitor, it is marked 500 (For 500uF) and 7.5V (For 7.5 Volt), but the charger can deliver 9V?

The bridge rectifier is 4 diodes (D01, D02, D03, D04). The mains switcher (U01: CR6853S) is a 8 pin IC, there is a opto coupler (OP01) for feedback.
On the low volt side there is a large rectifier diode (D21) placed below the usb connector (I wonder why a 330kOhm resistor is called D24). There is a 8 pin IC (U02) to handle the 9V QC and a reference (U3: 431) for the opto feedback.

The distance between mains and low volt is slightly below 5mm here.

And here it is about 4mm from the track that goes below the opto coupler to the capacitor (C10). See top view above for a better picture.

The charger passed the 2830 volt and the 4242 volt this makes it fairly safe.

Conclusion

A Samsung charger from Ebay, is this a real on or a fake one?
The circuit board do not say Samsung anywhere, but that could be because Samsung bought from some other manufacturer.
Mostly it looks real, but the high noise, the low safety distance and a 7.5V capacitor with 9V applied makes me believe it is fake.

I will not recommend this charger.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Coosa 5 Port USB Type C PD 72 W Charger PDS75-4UT01

Official specifications:

Material: Rigid Plastic
Input: 100 – 240Vac 50/60Hz
Output: USB (a): 5 V/2.4 A
USB c: 5 V and 9 V, 12 V, 15 V, 20 V and 3 A
AC – Discharge Current: 0.25 mA Max at 240 VAC input
Ripple and noise: Less than 100 mV Vpp
Switching the delay time: 3s Max
Rise Time: 20 ms
USB (a): >= 80%
USB c: >= 81.4%
Operating temperatures: 32º F to 140º F (0º ~ 40 °C)
Storage Temperature Range: -20 ~ 80 °C
Working relative humidity: 5% ~ 90% RH
Colour: Black
Size: 91 × 75 × 27.5 mm
Weight: 220 g (Main body without mains cable)

I got it from amazon.de dealer: COOSA®

I wonder about some of the specifications, the “Discharge current” must be the leak from mains to low volt side, the rules says it has to be below 0.25mA, this matches the specification (A measurement also shows it to be below 0.25mA).
The two percent specifications must be efficiency and matches fairly well with my measurements.

I got it in a cardboard box with specifications on the back.

It contained the charger and a mains cable.

Measurements

Power consumption when idle is 0.16 watt
PD output supports: 5V 3A, 9V 3A, 12V 3A, 15V 3A, 20V 3A
PD output also support DCP and QC2
Default PD output is off.
Regular usb output are auto coding with Apple 2.4A, Samsung and DCP
Regular usb outputs are in parallel.
PD and regular usb are isolated fro each other.
Weight: 232g
Size: 91 × 72.2 × 27.6mm

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20%232%20230V%20load%20sweep

The regular usb output can deliver 3.5A, this is a bit high for a 2.4A rating.

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20%234%20230V%20load%20sweep

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20%234%20230V%20load%20sweep

Another regular usb output can deliver the same.

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20%23234%20230V%20load%20sweep

Running all 3 usb outputs in parallel is also the same.

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20%23234%20120V%20load%20sweep

Not much difference at 120VAC.

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20PD5V%20230V%20load%20sweep

PD at 5V can deliver 3.5A, this is fine for a 3A rated output.

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20PD9V%20230V%20load%20sweep

At 9V it is also 3.5A

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20PD12V%20230V%20load%20sweep

And the same at 12V

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20PD15V%20230V%20load%20sweep

And at 15V

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20PD20V%20230V%20load%20sweep

And finally at 20V, this is the 60W rated output.

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20PD20V%20120V%20load%20sweep

The output is the same at 120VAC

Coosa%205%20Port%20USB%20Type%20C%20PD%2072%20W%20230V%20load%20test

For a load test I used 20V 3A and 5V 2.4A for one hour, it worked fine.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp6001

M1: 66.7°C, M2: 66.1°C, M3: 60.7°C, HS1: 72.4°C
This IR picture is a nice map of the inside: HS1 is the PD transformer, M2 is the regular usb transformer, M1 is the heatsink for the switcher transistors and M3 is the heatsink for the PD rectifier.

Temp6002

HS1: 61.2°C
HS1 is the regular usb transformer.

Temp6003

M1: 64.5°C, M2: 47.6°C, HS1: 64.9°C

Temp6004

M1: 52.3°C, HS1: 53.0°C

Temp6006

M1: 54.7°C, HS1: 64.4°C

10ohm

At 0.5A the noise is 16mV rms and 253mVpp.

5ohm

At 1A the noise is 25mV rms and 216mVpp.
2ohm

At 2.5A the noise is 32mV rms and 182mVpp.

10ohmPD5V

At PD 5V 0.5A the noise is 16mV rms and 239mVpp.

5ohmPD5V

At PD 5V 1A the noise is 16mV rms and 259mVpp.

2ohmPD5V

At PD 5V 2.5A the noise is 15mV rms and 342mVpp.

10ohmPD12V

At PD 12V 1.2A the noise is 20mV rms and 264mVpp.

10ohmPD20V

At PD 20V 2A the noise is 23mV rms and 321mVpp, all noise values are fairly low.

Tear down

This type of charger is usual very easy to open: mount the front in a vice and give the enclosure a whack with a mallet, this breaks the glue holding the front. In this case there was a problem, I could not pull the circuit board out. This improves the safety of the charger, because there is nothing dangerous to touch on the exposed parts.

I had to cut before I could get the circuit board out, somebody had used the white stuff to glue the circuit board in place.

With all the white stuff and heatsinks some of the parts are hidden, but it is still possible to see most of the circuit. Next to the large mains smoothing capacitor is a bridge rectifier.
On the blank heatsink are two mains switcher transistor, one for 5V and one for PD, next to the PD transistor is the opto feedback (U4) and a blue safety capacitor.
The large transformer is for the 60W PD output and the small transformer is for the 12W normal usb output.
On the golden heatsink is mounted a transistors for synchronous rectification together with a diode, both for PD. There two small circuit board, one for the USB-C connector and one for the PD controller.

There is not much to see from the front. The board with the USB-C connector do not have any parts on it, there is 6 connections to the main circuit board. 2 power and 4 control.

From the back a fuse, a inrush current limiter and two common mode coils can be seen.

On the mains side is two switchers one for PD (U1) and one for 5V (U2: Marked FD745). On the low volt side for 5V there is a synchronous rectifier controller (U7: LN5S01) that controls a SMD transistor (Q6) to rectify normal usb. There are two auto coding chips (U5: CX1901A, U6: CX2901A).
The PD output only has a on/off switch (Q5) on this side, the rest is on a small circuit board.

This small circuit board handles the PD, both the protocol, the regulation to the opto feedback and the synchronous rectification controller.

The distance between mains and low volt side looks fine.

The charger passed the 2830 volt and 4242 volt test, this means it is it is fairly safe.

Conclusion

As a 60W PD supply this charger is fine, but as a regular usb charger not as much, with only 2.4A for 3 outputs is is serious under powered, it only has power for one regular usb output. I did not see any safety problems in it.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Urant USB-C PD 45W car

Official specifications:

Input: DC 12V-24V
Output Type C: 45W (5V/3A,7V/3A,9V/3A,12V/3A,15V/3A,20V/2.25A)
Output QC 3.0: 24W (3.6V-12V/2A)
Size: 65×35×25 mm
Weight: 40g
Color: Black

I got it from Aliexpress dealer: Jinser Ltd’s store

Measurements

PD codes: 5V 2.39A, 9V 2.39A, 12V 2.31A, 15V 2.07A, 20V 2.07A This do not match the specifications
PD outputs starts enabled.
PD output is coded as Apple 2.1A and PE2.0 up to 20V, the marked QC is not present.
QC output is auto detect with DCP, Apple 2.4, QC3, PE1.1, Huwai-DCP, Huwai-SCP, Samsung-FCP
Minimum QC3 voltage is 3.6V
Power consumption when idle is 28mA from 12V and 13mA from 24V

The charger has many different output voltages and with input support up to 24V this makes for many combinations, I have tested many of them, but will not show all here.

No%20load%20voltage%20sweep

Power consumption when noting is connected to output depends on input voltage.

QC output

Load%20sweep%2011.6V

5V output with low input voltage, this looks good up to about 1.8A, the efficiency goes down, but it can deliver the rated 2A.

Load%20sweep%2011.6VQC9V

9V output, again with low input voltage, the output can nearly deliver the rated 2A.

Load%20sweep%2011.6VQC12V

12V output with low input voltage is a bit problematic (This is the same on just about any car charger), it gets nearly up to 2A before it drops to 5V.

Load%20sweep%2014.6VQC12V

12V output with high input voltage can deliver exactly 2A

Voltage%20sweep%202A%20input%20current

In these curves I sweep voltage from 24V and down with a output load of 2A, this one shows the input current with 5V output.

Voltage%20sweep%202A

The 5V output is stable down to about 10V input.

Voltage%20sweep%202AQC9V

9V output can be maintained down to about 12.7V input, again with a 2A load

Voltage%20sweep%202AQC12V

12V output works down to about 14.5V, also notice that the output is only 11V with 24V input.

10ohmQC5V

At 5V 0.5A the noise is 30mV rms and 278mVpp

5ohmQC5V

At 5V 1A the noise is 22mV rms and 110mVpp

2.5ohmQC5V

At 5V 2A the noise is 54mV rms and 547mVpp, this is a bit high.

10ohmQC9V

At 9V 0.9A the noise is 31mV rms and 264mVpp

10ohmQC12V

At 12V 1.2A the noise is 116mV rms and 595mVpp, this is rather high, but it is also at the overload limit.

PD output

Load%20sweep%2014.6VPD5V

USB-C PD with 5V output and high input voltage can deliver about 3.5A, this easily matches both the specifications and coding. But the power loss is fairly high at higher current and may prevent the charger doing it for much time.

Load%20sweep%2014.6VPD9V

9V can easily match the coded current and more.

Load%20sweep%2011.6VPD12V

12V output with low input voltage, surprisingly the output current is much higher. The lower voltage is not as surprising.

Load%20sweep%2014.6VPD15V

15V can deliver about 2.5A, before the voltage drops a bit and it then delivers 3.5A. The drop looks like the boost converter passes the input voltage, instead of boosting it.

Load%20sweep%2014.6VPD20V

20V is maximum output and it can deliver about 2.2A before the boost converter gives up.

Load%20sweep%2024.0VPD20V

With 24V input only the buck converter is used and the output can deliver 2.4A, before slowly dropping.

Voltage%20sweep%202APD5V%20input%20current

Voltage%20sweep%202APD5V%20input%20current

Due to the boost converter 5V output works down to about 4V input voltage.

Voltage%20sweep%202APD12V

The 12V output works down to about 6V input, but the power loss in the adapter is rather high when using the boost converter.

Voltage%20sweep%202APD20V

With 20V output the input voltage must be above 11.5V

Load%20test%2020V2A

Using 12V input with 20V output is a bit hard on the adapter, because it has to use the boost converter. Here it could handle it for about 3 minutes. This is not going to charger a laptop or tablet computer.

Load%20test%2020V1.5A

Reducing the load to 1.5A did increase the time to 10 minutes.

Load%20test%2020V1.0A

At 1A I could do a one hour test.

The temperature photo below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5498

M1: 48.2°C, M2: 44.6°C, HS1: 54.2°C
The charger gets warm, but the temperature do not look problematic.

10ohmPD5V

At 5V 0.5A the noise is 15mV rms and 99mVpp

5ohmPD5V

At 5V 1A the noise is 22mV rms and 110mVpp

2ohmPD5V

At 5V 2.5A the noise is 18mV rms and 145mVpp

10ohmPD9V

At 9V 0.9A the noise is 26mV rms and 170mVpp

10ohmPD20V

At 20V 2A the noise is 30mV rms and 414mVpp

Tear down

With a bit of force it was possible to pull the front of this charger.

It has 3 inductors, the one on the “main” board boost the input voltage to 24V and the two on the usb board is for PD and QC respective.

The boost converter uses a diode for rectification, that may be acceptable, the current is fairly low at 24V.

The boost converter chip is hidden below the inductor.
The “fluff” around the back of the adapter is because the input capacitor has vented (OOPS, not good).
The reason it vented is probably because it got too hot, this charger is supposed to handle very high power levels and with two converters in series there will be a lot of loss in it.

On the bottom is a power mos (AON6154) and a 9V regulator to supply the converter.

On this side is the two usb connectors, a led, a inductor, one capacitor, but there is space for two.

The two buck converter and usb interface chips are here. IP6518 is for PD, the other chip is for QC.

Being a 12V device there is no need to test with high voltages.

Conclusion

This car charger has a couple of issues, firstly the printed specifications is way overrated compared to the electronic reported specifications and any PD device will use the electronic reported value, sadly they are also overrated compared to what the charger can do.
During test the charger shorted its input at one time, the is no issue with a lab power supply, but in a car it will blow a fuse. Disconnecting the charger and reconnecting it fixed the problem.

The support for many different fast charge schemes is a nice detail.

I will only call it usable and keep any USB-C high speed charging tablets and laptops away from it.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

YZXStudio USB meter ZY1280

Official specifications:

Item: ZY1280
Size: 57*35*12
Display: 1.8 inch TFT
Resolution: 160*128
Communication: USB2.0
Input port: A male M female C female
Output port: A female C female
Online mode: MicroUSB
Fast charge trigger: YES
PD trigger: YES
PD straight through: YES
Fast charge straight through: All models support the normal fast charge protocol through the meter
VOOCDASH: Need original line *2
Upgrade method: NicroUSB
Voltage accuracy: 0.1%±2d
Current accuracy: 0.1%±2d
Internal resistance is less than: 32mOhm
Open screen power consumption: 19mA
Off screen power consumption: 3mA

YZXStudio makes a series of usb meters, some of them very advanced.

I got the meter in a small metal can

Maximum specifications and connector information is listed on the back.

The two USB-C connectors and a micro usb connector are on this side.

The USB A connectors are at the ends.

A usb connector for PC link and the button for all user interface is here.

Display and functions

The screen with most information about current and voltage. The small voltage and current are maximum and minimum values for this session. The arrow shows current direction.
Hold down the button to select group from 0 to 5, they are used to save the recorded values.

Next screen is nearly the same, but Wh and Ah is replace with load resistance and time.
Hold down the button to select configuration.

Next screen is the fast charge screen, it shows the voltage on the data wires and tries to guess the protocol. If multiple protocols match the voltage, it will show multiple protocol names.
Hold down the button to select a fast charge trigger or scan for fast charge protocols.

Next screen is cable resistance measurement, it requires a constant current load and a fairly stable usb supply. First connect the usb meter directly to the power supply and hold down the button, then connect using the cable and the display will show cable and connection resistance.

Next screen is curves. It can either show voltage and current or the data lines, hold down the button to switch between them.
The curves will auto scale, this means they are fairly sensitive for even small variations.

Next screen is a simple screen with voltage, current and power.
Hold down the button to flip the screen, the orientation will be used for all screens.

The last screen is “screen off”, then the sequence starts from the first screen again.

When holding down the button to activate fast charge menus a warning is shown, press the button two times and hold it down to enter. It is not possible to enter while current is being drawn.

There is a long list of supported fast charge schemes and other functions.

Selecting a scheme may present more options.

The Auto detect option will try most options and report on result.

Selecting PD will query the charger for supported PD voltage and list them. It is possible to select one and activate it.

There is many configuration settings, including the possibility for user calibration.

Measurements

USB-C output will be triggered when this device is connected, as standalone, but not when used between a PD device and supply.
The usb meter uses about 19mA current with normal brightness (10), 6 with display off.
The internal resistance is about 0.060ohm (This includes both connectors).
Usb meter will remember measured values when power is removed.
USB meter uses software V3.36E
Fast charge protocols supported: QC2, QC3, Huwai-FCP, Huwai-SCP, Samsung-AFC, Apple, Samsung, DCP
Backlight timeout can be adjusted in 1 minute steps up to 10 minutes, then in 5 minutes steps up above 4 hours or turned off.
Curve update can be 0.1s/div, 0.2s/div, 0.5s/div, 1s/div, 3.6s/div, 5s/div, 10s/div, 20s/div (The settings did not work in my software version).
It is possible to select between 5 and 6 digits, the 5 digits will update faster.

The voltage display is very precise with no current flowing, but there is too many digits.

Current

The current display is also very precise and will not change with voltage and again there is too many digits.

Temp5804

M1: 40.0°C, HS1: 43.8°C

Temp5805

M1: 43.7°C, HS1: 51.8°C

The above IR photo was taken after 30minutes with 5A, during that time the readouts changed very little.

PC application

One of the usb connectors is a PC connection that allows external power supply, software updates, logo updates and transferring the data to the PC.
I could not find the application and it looks like it is in Chinese anyway.

This is a random image from the internet showing the PC application.
When using the PC application it is important that the PC do not have any connection to the devices that is measured on, i.e. do not use the same PC for usb output and measure input.

Tear down

It is very easy to open, there is four screws on each side.
The top and bottom are the same on both sides.

The processor is a GD32F330F8P6 (ARM Cortex-M4 64kB flash, 8kB ram) . The chip (CH330) near the PC usb connector is a standard serial to usb converter. The other 8 pin chip is most likely a parameter memory and the two smaller chips are most likely usb interface for PD and a ADC converter. The sense resistor is a 0.012ohm resistor.

The power supply can either come from testing USB connectors through a regulator (SE8533) and transistor or from PC usb through another regulator (SE8536) through a diode, any voltage here will block the transistor that delivers power from the testing connectors.

On this side is only the display and a usb connector, there is nothing below the display.

Conclusion

This is a very advanced usb meter, with good precision and lots of functions. The fast charge test and trigger functions for both old usb and PD type supplies can be very useful when testing usb supplies or finding out what chargers will charge a device the fastest.
The bug with the curves reduces the usefulness of the curves and due to the difficult with finding software for this meter it might not be easy to get an update to fix it.

I will rate it as a very good usb meter and it is my favorite usb meter.

Notes

For these USB meters I used precise equipment (Keithley: DMM7510, 2280S, Keysight: 34470A).

How do I make the test

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Xiaomi/Mi’s single 18650 USB power bank with LED flashlight. It’s kind of old and has been reviewed before, but this is the first time I’ve seen the instructions in English. Hopefully this will be useful to someone. With its English packaging it looks like they’re going to start selling this internationally. I don’t expect the hardware to be different from the Chinese version.

On the packaging:

Model: LPB01ZM
Input: 5.0V 1.0A
Light source wattage: 3W MAX
Cell capacity: 3250mAh 3.63V 11.8Wh
Color: White
Onput: 5.0V 1.0A
Max. lumens: 190LM/240LM (MIN/TYP)

On the sticker over the USB ports:

Quickly press the Function key three times to activate SOS mode.
Press the Function key once to exit SOS mode.

Instructions:

I’m not typing them out. Here are the key points:

It’s not an on/off button – “The Function button is not an On/Off button. No button operation is needed since the product detects charging and discharging automatically. The power level indicator will shut off 2 minutes after the battery is fully discharged.”
You need to click 3 times quickly to turn it on. A lock out protection of sorts.
Press 3 times for SOS mode
You can rotate or click once to turn it off
Cannot use flashlight and USB out at the same time.
Cannot charge and use flashlight at the same time.
There seems to be over-current protection – “If the product enters protected mode (LEDs do not respond after pressing the button) due to a short circuit or other causes, simply connect it to an external charger to resume operation”

Now here’s something new – you know how power banks will shut off if your current draw is too low, making it impossible to charge small devices like smart watches? This has a special mode to force it to stay on!
Double-click, and the LED will flash red-off-orange-off-green-off-. It’ll stay on for 2 hours. I’ve never seen this feature before. The timer is handy since I’ll probably forget it’s in this mode.

The adjustment rotates infinitely, like a mouse scroll wheel. Not like Nitecore’s recent variable series (EC22, MT22C etc.) which can only rotate, say, 270°. I think the electronics are interesting because this design is harder to make than just a rheostat, and it lets them put in features like the 3 clicks to turn on. I’ve heard that sometimes it skips and doesn’t change when it clicks. I haven’t seen this, and since it rotates continuously, just keep rotating. It’s not like a tap that you’ve tightened all the way and continues to drip. My car stereo skips if you rotate too fast too.

To be continued…

Forums:

USB Power Device Reviews

Dual USB Wall charger Keke-F5

Official specifications:

Input: 120-240V AC
Output: 5V 2.1A

I got it from ebay dealer ddarlingshop

It was packed in a plastic bag inside the usual envelope.

Behind the two green teardrops (one on each side) is a led.

Measurements

Power consumption when idle is 0.15 watt
One USB output code with Samsung.
The other usb output is usb charger (DCP).
The two outputs are in parallel.
Weight: 27.4g
Size: 78 × 36.7 × 24.7mm

Dual%20USB%20Wall%20charger%20Keke-F5%20%231%20230V%20load%20sweep

The charger can deliver 1A, not the rated 2.1A

Dual%20USB%20Wall%20charger%20Keke-F5%20%232%20230V%20load%20sweep

It is the same on the other port.

Dual%20USB%20Wall%20charger%20Keke-F5%20230V%20load%20sweep

And when using the ports in parallel.

Dual%20USB%20Wall%20charger%20Keke-F5%20120V%20load%20sweep

Using 120VAC gives the same result.

Dual%20USB%20Wall%20charger%20Keke-F5%20230V%20load%20test

Running 1 hour at 1A worked fine.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5882

M1: 56.8°C, HS1: 58.7°C
HS1 is the transformer and M1 is the rectifier diode.

Temp5883

M1: 44.1°C, HS1: 53.3°C

Temp5884

HS1: 44.1°C

Temp5885

M1: 53.3°C, HS1: 57.0°C

10ohm

At 0.5A the noise is 97mV rms and 688mVpp.

5ohm

At 1A the noise is 114mV rms and 635mVpp.

Tear down

Placing the charger in my vice and whacking one with my mallet did open it.
The green teardrops was not glued and if they fall out the charger is very dangerous to touch.

On this side is the input fuse (RF1: Fusible resistor), a bridge rectifier, the two leds and a large rectifier diode.
The “blue safety capacitor” is not a safety capacitor, but just a 1000V capacitor.
It is interesting to see the circuit board is marked 1A, this matches the output of the charger, but not the external marking.

On this side it the mains switcher.

Creepage distance is about 2mm, this is way to short.

Testing with 2830 volt and 4242 volt failed the 4242V test, this means it is unsafe in 230V countries.

Conclusion

The charger is a 1A charger with a lot of noise.
Too short distance between mains and usb, together with a unsafe capacitor, this rather bad safety.

Stay away from this charger.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

UNI-T UT658 USB tester

Official specifications:

Brand: UNI-T
Model: UT658B
Input voltage: DC 3V-9V
Load current: 0.0A~3.5A
Charge monitoring: 0~39999mAh
Data storage: 10 sets

I bough it on Ebay.

UNI-T makes a lot of test equipment, this time they have made a USB meter.

It arrives in a white cardboard box.

It has a display and one button.

Limits are embossed on the back, it only goes to 9V., this means it is not to be used on Quick Charge.

There is a protective cover over the usb A connector.

Display and functions

This is a rather simple usb meter, it shows the voltage, current and capacity (mAh).
Pressing the button will change to next memory bank and holding down the button will reset the current memory bank.
There are memory banks from 0 to 9.

The meter is rated for 40Ah (40000mAh) and will show OL when above (I have not tested this).

Measurements

The usb meter uses about 6mA current.
Usb meter will show OL when current is above 3.2A.
The internal resistance is about 0.11ohm (This includes both connectors).
Data wires goes through the meter.
Usb meter will remember measured values when power is removed.
The only permanent memory is the main flash memory, this has a limited number of writes, i.e. the mAh memory may die after some time.

The voltage display has good precision within the resolution.

Current

The current display has also fairly good precision within the resolution, but error increases at high currents.

Temp5806

M1: 43.3°C, HS1: 43.4°C

Temp5807

M1: 33.2°C, HS1: 47.1°C

The above IR photo was taken after 30minutes with 3A, during that time the voltage readouts was stable and the current readout increased about 2%

Tear down

I could just pry the meter apart, the screws are for the display cover and was not necessary to remove.

This side is only for display, button and usb connectors, behind the display is the backlight panel.

Display with cover mounted.

The microprocessor (U1: SN8F57082 8051 based, 16k flash, 1256b ram, 12 bit ADC), this means U2 (COP) must be a LCD driver chip. The internal power supply is with a diode (D2) and a regulator (U4: marked PAO) and is 3.3V. There is a 0.05ohm sense resistor and a voltage divider (R2 & R3: 4700 & 1000).

Conclusion

This is a simple and “low precision” usb meter, but the precision is more than enough to show what voltage there is on a usb supply and how much current is drawn. Together with a load it can also be used to measure capacity of power banks.

This meter is good enough for most applications.

Notes

How do I make the test

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

GUSGU Dual USB Charger LED Display LQ-008

Official specifications:

Model No.: GUSGU DUAL USB LED Charger
Input: AC 100-204V ~ 50-60Hz 0.4A
Total output: 5V/ 2.4A
Single port output: 5V/2.4A(Max.)
Material: fireproof PC
Weight: 57g
Dimension: 80×45×28mm

I got it from aliexpress dealer GUSGU BrandFlagship Store

I got it in a plastic bag with some text on that has nothing with the charger to do.

The charger has a display showing voltage and current for both usb output together, the button is used to change between current and voltage. It will also change automatic at the start of a charge. Display will only turn on during charging.

Measurements

Power consumption when idle is 0.1 watt
Display turns on at around 0.15A
Both USB output is auto coding with Apple 2.4A and DCP
The two outputs are in parallel.
Weight: 53.2g
Size: 82.2 × 45 × 28.7mm

The meter do not show the same current for the two outputs.

GUSGU%20Dual%20USB%20Charger%20LED%20Display%20%231%20230V%20load%20sweep

The output can deliver about 2.5A, this matches fine with a 2.4A rated charger.

GUSGU%20Dual%20USB%20Charger%20LED%20Display%20%232%20230V%20load%20sweep

GUSGU%20Dual%20USB%20Charger%20LED%20Display%20%232%20230V%20load%20sweep

The other output port is the same.

GUSGU%20Dual%20USB%20Charger%20LED%20Display%20230V%20load%20sweep

And both ports at the same time is also the same.

GUSGU%20Dual%20USB%20Charger%20LED%20Display%20120V%20load%20sweep

Also at 120VAC

GUSGU%20Dual%20USB%20Charger%20LED%20Display%20230V%20load%20test

Running 1 hour at 2.5A worked fine.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5915

M1: 62.3°C, HS1: 72.8°C
HS1 is the output capacitor and the transformer is next to it.

Temp5916

M1: 45.8°C, HS1: 60.2°C

Temp5917

HS1: 75.1°C
HS1 is the transformer.

Temp5918

HS1: 73.8°C

Temp5919

HS1: 72.1°C

10ohm

At 0.5A the noise is 93mV rms and 979mVpp.

5ohm

At 1A the noise is 130mV rms and 953mVpp.

2.5ohm

At 2A the noise is 172mV rms and 1068mVpp.

Tear down

I mounted it my vice and gave it a few whacks with my mallet, that broke the glue and then I could break it apart.

Circuit board in box, when put together there is a pice of white plastic behind the display board.

On this side is the input fuse (F1: 4.7ohm/1W fusible resistor), a “blue safety capacitor” (CY1) that is not a safety capacitor.
This display board is also mounted on this side.

On this side of the display board if the display, a switch and probably a 3.3V voltage regulator (U5: 662K: XC6206)

On the backside is the voltmeter chip.

On this side is the input bridge rectifier (BD1), the switcher (U1: CSC7158), on the low volt side is a synchronous rectifier (U2: SA2212A) and a auto coding chip (U4), it is connected to both usb ports, i.e. both are supposed to be auto coding.
There is two R100 resistors in parallel for measuring the current. I have a suspicion that the current sense is at R0, but the sense resistors are R13 & R14 and that is the reason for the difference between the two usb outputs.

Creepage distance is about 1.5mm, this is way below the required distance.

Testing with 2830 volt and 4242 volt failed the 4242V test, this means it is unsafe in 230V countries.

Conclusion

It is a nice idea with a ammeter on the usb charger, but that is about the only nice thing about this charger. The isolation distance is way too short and it do not use a real safety capacitor, both are very bad for safety, in addition to this the output has a lot of noise.

Stay away from this charger.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Baseus Dual car charger C8-K

Official specifications:

Brand Name: BASEUS
Output: 5V/3A
Power Source: Car Lighter Slot
Type: Car Charger
Support Quick Charge Technology: No
USB Ports: 2
Quality Certification: CE,RoHS,FCC,CCC
Output Interface: USB
Model Number: Baseus Grain Dual USB Car Charger
Input: 12-24V/2.4A
Material: PC+ABS
Color: Black/White
Input: DC 12V-24V
USB1+USB2 Output: 5V/3.1A Max

I got it from Aliexpress dealer: BASEUS OfficialFranchised Store

The charger arrived in a box with specifications on it.

It included the charger and a instruction sheet.

Measurements

Both usb output are auto code with Apple 2.4A, DCP and Samsung (Not all my testes could see the auto coding).
The two usb outputs are in parallel.
Power consumption when idle is 7mA from 12V and 4mA from 24V
There is a blue led behind the usb connectors.
Weight: 12.1g
Length: 44mm
Front: ø24.2mm

The first usb connector can deliver slightly above 3A

Load%20sweep%2011.6V%202

The second is the same.

Load%20sweep%2011.6V

When working together the total is also slight above 3A

Load%20sweep%2014.6V

Voltage do not change this.

Voltage%20sweep%202.0A%20input%20current

Power loss is independent of voltage and fairly low.

Load%20test%203.1A

The output cannot deliver 3.1 for more than a few minutes.

Load%20test%202.7A

I dropped the current to 2.7A and there was no problem running for one hour.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5687

M1: 49.6°C, HS1: 57.4°C

Temp5688

HS1: 62.2°C

10ohm

At 0.5A the noise is 23mV rms and 147mVpp

5ohm

At 1A the noise is 24mV rms and 140mVpp

2ohm

At 2.5A the noise is 30mV rms and 152mVpp

Tear down

I could remove the front from this charger and then push the electronic out.

This side has a fuse (F1) at the input the switching IC and two smoothing capacitors (C4 & C5).

On this side is the inductor (L1), TVS diode (D5: 6V2) across the 5V output and the auto coding chip (U2).

There is two leds, one on each side of the circuit board, they are not visible on the photo, because they are mounted below the usb connectors.

Being a 12V device there is no need to test with high voltages.

Conclusion

This is a nice little adapter with enough power to charge one high power device or two device with more moderate charge requirement. The design is fairly simple, but it has what is needed, including auto coding.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

RD USB Meter TC64

Official specifications:

Product Model: TC64
Display screen: 0.96 Inch color LCD display
Voltage measurement range: 3.70 – 30.00V
Voltage measurement resolution: 0.01V
Current measurement range: 0 – 4.000A
Current measurement resolution: 0.001A
Capacity accumulation range: 0 – 99999mAh
Voltage measurement accuracy: ±(0.8% + 4 digits under 25°C)
Energy accumulation range: 0 – 99999mWh 999.99W
Current measurement accuracy: ±(1% + 4 digits, under 25°C)
Load impedance range: 1ohm- 9999.9ohm
Power measurement range: 0 – 120W
Temperature range: -0°C ~ 80°C / 32°F ~ 176°F
Temperature measurement error: ±3°C / ±6°F
Working temperature range: 0°C ~ 45°C / 32°F ~ 113°F
Product size: 50mmx19mmx9mm
Refresh rate: 2Hz
Product weight: 7g (With packaging 14g)
Quick charge recognition mode: QC2.0, QC3.0, APPLE 2.4A/2.1A/ 1A/0.5Am Android DCP, SAMSUNG

This is a USB meter with color display for USB-C, it has fast charge protocol information, but not for PD.

I got the meter in a plastic box, it did not include a manual, but a link where to download it.

The button is placed on this side.

Display and functions

The main screen with voltage, current, capacity, energy, power, temperature, bank and load equivalent resistance. The temperature is the internal temperature of the tester. There is two banks to store data in.
The icons on the right are different functions, when the button is held down a marker will slowly more down the list, release button to activate that function.
The functions are: Display off, Temperature in °C or °F, change bank, clear bank (Bank 0 is auto reset), flip display.

A fast press on the button will change between the two screens, this is the protocol screen with data line voltage and a guess about the used protocol.

Here a Quick Charge 2.0 protocol is activated and the voltage display shows 12V

Measurements

The usb meter uses about 14mA and 7mA with display off.
The meter will not enable a USB-C output, this must be done by the connected device.
The meter will not show PD fast charge protocol.
The internal resistance is about 0.1ohm (This includes both connectors).
Usb meter will remember measured values when power is removed.
Bank 0 will show remembered value, but automatic reset when drawing current after a power break.
Meter only support current one way (USB-C is bidirectional).
Voltage display is within 0.5% when no current is flowing.
Current display is within 0.2% when voltage is within specifications.
Software in tester is V1.4

The voltage display has good precision with no current flowing.

Current

The current display is also precise.

Temp6030

M1: 56.0°C, HS1: 64.1°C

Temp6031

M1: 59.6°C, HS1: 68.1°C

The above IR photo was taken after 30minutes with 4A.
The readings did not change, the internal temperature readout showed 58°C

Tear down

8 small screws and it was open on both sides. To see the electronic I did only need to remove the bottom four screws.

The microprocessor is 8051 based (U4: N76E003AT20 18KB Flash, 1k RAM, 12 bit ADC), to save the data it used a EEPROM (U1: HT24LC64: 8kB 1 million write/word). The current measuring circuit is a 0.01ohm resistor and a OpAmp (U2: Marked 541IG). To power the circuit is a regulator (U0: M5333B: 3.3V). The button is also here.

The display covers this side, it is mounted with some sticky tape.

Conclusion

This is a small compact usb meter with a easy readable color display it saves Ah & Wh and show protocol information this makes it a very versatile meter with enough precision for most usages, but it is missing PD support.

Notes

For these USB meters I used precise equipment (Keithley: DMM7510, 2280S, Keysight: 34470A).
The usb meter was supplied by Rui Deng (RD) for review.

PD is the USB-C protocol for power delivery, devices made for USB-C exclusive will use this.

How do I make the test

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Anker PowerPort Speed 5 2xQC3 A2054

Official specifications:

Charging Ports: 5
Wattage : 63W
Output Currency: 3.6V-6.5V / 3A, 6.5V-9V / 2A, 9V-12V / 1.5A
Size: 10.2 × 7.5 × 2.8 cm
Weight: 295 g

I got it from a amazon.de dealer: AnkerDirect DE

I got it in a cardboard box.

The box included the charger, a mains cable, a welcome guide (Instruction sheet) and a adhesive strip to mount the charger somewhere.

Measurements

Power consumption when idle is 0.2 watt
2.4A USB outputs is auto coding with DCP, Samsung, QC5V, Apple 2.4A
QC USB output is auto coding with QC3, DCP, Apple 2.4A, Huawei-FCP
Minimum QC3 output is 3.6V
2.4A outputs are in parallel.
QC and 2.4A outputs share minus connection.
Weight: 222g without mains cable
Size: 102 × 74.7 × 29mm

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%231%20230V%20load%20sweep

The output has cable compensation and there is no individual port protection.

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%233%20230V%20load%20sweep

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%233%20230V%20load%20sweep

This output looks the same.

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%23123%20230V%20load%20sweep

Running all 3 2.4A output in parallel I can see the overload protection is at around 5.5A, this is a high current for a single usb port.

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%235%20230V%20load%20sweep

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%235%20230V%20load%20sweep

At 5V the QC port can deliver about 3.5A (I did run this test on both QC port, they are very similar).

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%235%20QC9V%20230V%20load%20sweep

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%235%20QC9V%20230V%20load%20sweep

This also holds at 9V

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%235%20QC12V%20230V%20load%20sweep

And even at 12V

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20%235%20QC12V%20120V%20load%20sweep

Using 120VAC do not change it.

Anker%20PowerPort%20Speed%205%202xQC3%20A2054%20230V%20load%20test

For load test I did 5V 4.8A and 2×12V 1.5A
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5936

M1: 58.5°C, M2: 51.6°C, HS1: 60.3°C
The heat profile matches the heatsink below (See tear-down). HS1 and M1 are the two transformers (HS1 is QC).

Temp5938

M1: 59.8°C, M2: 54.5°C, HS1: 61.2°C (The “Barcode” is a fault from my camera or memory card, this is the only time I have seen it).

Temp5939

M1: 53.9°C, HS1: 55.9°C
HS1 is one of the mains switchers.

Temp5940

M1: 45.6°C, HS1: 57.0°C
Again HS1 is one of the mains switchers.

Temp5937

M1: 55.3°C, HS1: 60.2°C

10ohm

Noise at 0.5A load is: 15mV rms and 126mVpp.

5ohm

Noise at 1A load is: 14mV rms and 244mVpp.

2ohm

Noise at 2.5A load is: 12mV rms and 152mVpp.

1ohm

Noise at 5A load is: 14mV rms and 163mVpp.

10ohmQC5V

Noise at 0.5A QC load is: 4mV rms and 99mVpp.

2ohmQC5V

Noise at 2.5A QC load is: 10mV rms and 205mVpp.

10ohmQC12V

Noise at 12V 1.2A QC load is: 5mV rms and 118mVpp, all values are very low.

Tear down

Some pressure with my vice and I could break the lid of with a screwdriver. The circuit board did not come loose, it is secured with a bit of glue.

A bit more breaking and it was out, notice the white pads on the lid, they are to improve heat transfer.

The transformers is very close to the top heatsink.

And there is some heat transfer paste between transformer and heatsink.

The heatsink is covered in yellow tape for isolation and a gray heat transfer pad.

At the mains input is a fuse (F1) and two common mode coils (L1, ?) followed by a bridge rectifier (BD1). There are two mains switcher transistors on for 5V 2.4A and one for 2xQC (Q2). Between the two transformers are two safety capacitors and one opto-coupler for QC.
One the low volt side are two rectifier transistors (Q14 & Q15, synchronous rectification). The QC outputs shares a common mode coil and there is a inductor for each, they are mounted on two small circuit boards with the a QC controller each. There is also a small circuit board with 3 leds for the indicator on the front.

With two transformers there must also be two switch mode controllers (U1 & U2). The opto-coupler for 5V is on this side (U3). For the 5V 2.4 outputs there is a synchronous rectifier controller (U4), a OpAmp (U7) together with a resistor (R69: 0.007ohm) to add the cable compensation to the reference (U8 and/or U10). Each of the 3 2.4A usb output has a auto coding chip (U11, U12, U13: probably CW3002).
The QC contains a 14.1V power supply that has a synchronous rectifier controller (U5) and a voltage reference (U9).
The actual QC controllers are on other circuit board that are soldered in slots with 6 connections on each side.

The square chip (U15: marked AGQH569) is probably the buck converter.

The QC controller is here (U20: Marked PJK789)

There is more than enough distance between mains and low volt side.

Testing with 2830 volt and 4242 volt between mains and low volt side, did not show any safety problems.

Conclusion

This is a good charger with lots of output current (I can fast charge 4 devices at a time), it has auto coding, low noise and two Quick Charge outputs.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

RD USB Meter AT34

Official specifications:

Product Model: AT34
Display screen: 1.44 Inch color LCD display
Voltage measurement range: 3.70 – 30.00V
Voltage measurement resolution: 0.01V
Current measurement range: 0 – 4.000A
Current measurement resolution: 0.001A
Capacity accumulation range: 0 – 99999mAh
Voltage measurement accuracy: ±(0.8% + 4 digits under 25°C)
Energy accumulation range: 0 – 99999mWh 999.99W
Current measurement accuracy: ±(1% + 4 digits, under 25°C)
Load impedance range: 1ohm- 9999.9ohm
Power measurement range: 0 – 120W
Temperature range: -0°C ~ 80°C / 32°F ~ 176°F
Temperature measurement error: ±3°C / ±6°F
Working temperature range: 0°C ~ 45°C
Product size: 64mmx22mmx12mm
Refresh rate: 2Hz
Product weight: 14g (With packaging 28g)
Quick charge recognition mode: QC2.0, QC3.0, APPLE 2.4A/2.1A/ 1A/0.5Am Android DCP, SAMSUNG

This is a USB meter with color display and fast charge protocol information.

I got the meter in a plastic box, it did not include a manual, but a link where to download it.

There is one push button on the back of the meter.

Display and functions

A fast press on the button will change between the two screens, this is the protocol screen with data line voltage and a guess about the used protocol.

Here a Quick Charge 2.0 protocol is activated and the voltage display shows 12V

Measurements

The usb meter uses about 16mA and 7mA with display off.
The internal resistance is about 0.081ohm (This includes both connectors).
Usb meter will remember measured values when power is removed.
Bank 0 will show remembered value, but automatic reset when drawing current after a power break.
Voltage display is within 0.5% when no current is flowing.
Current display is within 0.3%, except when voltage is below specifications.
Software in tester is V1.4

The voltage display has good precision with no current flowing.

Current

The current display is also precise.

Temp6028

M1: 47.6°C, M2: 43.6°C, HS1: 48.3°C

Temp6029

M1: 42.7°C, HS1: 48.0°C

The above IR photo was taken after 30minutes with 4A.
The readings did not change, the internal temperature readout showed 58°C

Tear down

There was no screws and I could just break it apart with a spudger.

On this side is the button and a EEPROM (HT24LC64: 8kB 1 million write/word)

The display covers this side, it is mounted with some sticky tape.

The microprocessor is 8051 based (N76E003AT20 18KB Flash, 1k RAM, 12 bit ADC), there is a 3.3V regulator (M5333B: 3.3V) for supplying it.

This side also has a 0.01ohm sense resistor and a OpAmp (Marked 541IG).

Conclusion

This is a small compact usb meter, but the easy readable color display, saved Ah & Wh and protocol information makes it a very versatile meter with enough precision for most usages.

Notes

For these USB meters I used precise equipment (Keithley: DMM7510, 2280S, Keysight: 34470A).
The usb meter was supplied by Rui Deng (RD) for review.

How do I make the test

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Xedain 4 port QC usb charger KeKe-QC-4

Official specifications:

Brand Name: XEDAIN
Support Quick Charge Technology: Qualcomm Quick Charge 3.0
Quality Certification: RoHS,CE,FCC
Output Interface: USB
USB Ports: 4
Power Source: A.C. Source
Input: 100-240V/0.5A
Output: 5V/2.4A
Model Number: 3.0XD4USB
color: White / Black
Output voltage current: 12V(1.5A)- 9V(2A)- 5V(3A) 5V(2.4A)
plug charger: US / EU

A reader send it to me.

i did not get a box or anything with it.

There is some text on the side, but it is very hard to read, it list the outputs as 5V:2.4A, 9V:1.8A, 12V:1.5A

Measurements

Power consumption when idle is 0.22 watt
There is a blue led behind the usb connectors.
Regular USB outputs are coded as usb charger (DCP)
QC USB output is auto coding with QC3, DCP, Apple 2.4A, Huawei-FCP
Minimum QC3 output is 3.7V
2.4A outputs are in parallel.
QC and regular outputs share minus connection.
Weight: 57.8g
Size: 88.2 × 45 × 26.8mm.

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20%231%20230V%20load%20sweep

The regular usb ports can delvier about 2.2A

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20%233%20230V%20load%20sweep

All of them.

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20%23123%20230V%20load%20sweep

Also when working together.

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20QC5V%20230V%20load%20sweep

With QC 5V the maximum output current is slightly above 3A.

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20QC9V%20230V%20load%20sweep

At 9V it drops to 2.2A

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20QC12V%20230V%20load%20sweep

And 1.7A at 12V

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20QC12V%20120V%20load%20sweep

At 120VAC it is about the same.

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20230V%203.6A%20load%20test

First I did a test with 2.1A on 5V and 1.5A on 12V, the charger could supply that for about 10 minutes before the 12V broke down.

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20230V%203.3A%20load%20test

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20230V%203.3A%20load%20test

Reducing the 12V to 1.2A helped a bit, now I could run for 23 minutes.

Xedain%204%20port%20QC%20usb%20charger%20KeKe-QC-4%20230V%203.1A%20load%20test

Reducing to 1A on 12V and still 2.1A on 5V I could run a one hour test.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5962

HS1: 89.1°C

Temp5963

M1: 42.0°C, HS1: 68.1°C
Temp5964

M1: 59.8°C, M2: 57.6°C, HS1: 65.6°C
HS1 is the transformers getting warm.

Temp5965

HS1: 79.3°C

Temp5966

HS1: 87.9°C

10ohm

Noise at 0.5A load is: 41mV rms and 1571mVpp.

5ohm

Noise at 1A load is: 41mV rms and 1535mVpp.

2.5ohm

Noise at 2A load is: 50mV rms and 1871mVpp.

10ohmQC5V

Noise at 0.5A QC load is: 143mV rms and 2321mVpp.

10ohmQC12V

Noise at 12V 1.2A QC load is: 95mV rms and 2374mVpp

Tear down

Mounting it in my vice and whacking it with my mallet popped the lid off.

In this side of the circuit board is a input fuse (F1), one switcher for QC with an opto coupler, two mains transformers and a blue 1kV capacitor (It was supposed to be safety capacitor). A led can also be seen between two usb connectors.

Here the 1kV can be seen, for the circuit to be safe a 8kV safety capacitor must be used.

This side has the bridge rectifier and the switcher for the regular usb outputs. Both switchers uses normal rectifier diodes (D4, D5 and D6), the regular usb output do not need any feedback, but on the QC side is a QC controller (U6) and a reference (U5: 431)

The distance between mains and low volt side is less than 3.5mm, this is way to low.

It failed both the 2830 volt and 4242 volt between mains and low volt side, this makes it unsafe to use anywhere in the world.

Conclusion

The power supply has lower than rated output current and lots of noise.
This is a rather bad and dangerous usb power supply, stay away.

Notes

The charger was supplied by a reader for review.

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Koyot Dual car charger 2.4A

Official specifications:

Brand Name: KOYOT
Output Interface: USB
Type: Car Charger
USB Ports: 2
Power Source: Car Lighter Slot
Output: 5V/2.4A
Support Quick Charge Technology: USB PD
Quality Certification: CE,CCC
Model Number: C188

I got it from Aliexpress dealer: Miss shen Wonderful Store

No fancy box for this charge, just an envelope and a plastic bag.

Measurements

2.4A usb output is coded as Apple 2.1A
1A output is coded as usb charger (DCP) and Samsung.
The two usb outputs are in parallel.
Power consumption when idle is 7mA from 12V and 4mA from 24V
Weight: 23.1g
Length: 69mm
Front: ø26.1mm

The 1A output can deliver about 2.8A

Load%20sweep%2011.6V%202.4A

The 2.4A output can also deliver about 2.8A

Load%20sweep%2011.6V

And when run in parallel the maximum current is also 2.8A

Load%20sweep%2014.6V

Higher input voltage do not change it.

Voltage%20sweep%202.0A%20input%20current

The output can maintain voltage until about 7V, also not the efficiency goes down when used at 24V

No%20load%20voltage%20sweep

The adapters own current consumption varies with voltage.

Load%20test%202.4A

There was no problem running 1 hour with full load (2.4A).
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5681

M1: 45.3°C, HS1: 50.3°C

Temp5681

M1: 45.7°C, HS1: 56.9°C

10ohm

At 0.5A the noise is 33mV rms and 170mVpp

5ohm

At 1A the noise is 39mV rms and 191mVpp

2ohm

At 2.5A the noise is 68mV rms and 269mVpp

Tear down

I could not pull or unscrew the metal and decided to cut.

The back has some heat shrink on it.

At the input is a “fuse” in the form of a 0ohm resistor, the voltage converter is a single IC (U1: marked VS2886) and it must have build in synchronous rectification (I do not see any diode).

There is no parts on this side of the circuit board.

The front circuit board has resistors for coding the two usb output, but there is also an empty space for a auto coding IC

Being a 12V device there is no need to test with high voltages.

Conclusion

This adapter works, but is not perfect. The power is enough for one high power output, not for two. Why is a 2.4A output coded for 2.1A, using a auto coding chip for both outputs would have been nicer.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Nokoko 4 port usb charger

Official specifications:

Input Voltage: AC 100-240V
Input Frequency Range: 50-60Hz
Output Voltage: 5V / 5.1A Max (2.1A + 1A + 1A + 1A)
ork Efficiency: 85%-95%
Working Temperature:0°C ~ +50°C
Storage Temperature: -20°C ~ +85°C.
Color: Red,Gold,Blue,Silver
Plug Type: US plug/EUplug
Size: 3.7*3.4*8cm / 1.5*1.3*3.1” (L*W*H)

I got it from Ebay dealer: purchase365

It arrive in a plastic bag inside an envelope.

Lot of markings on the front, but all outputs are exactly the same.

Measurements

Power consumption when idle is 0.15 watt
There is a two blue leds behind the usb connectors.
All usb outputs are coded with usb charger (DCP)
All usb outputs are in parallel.
Weight: 39.4g
Size: 79.4 × 37.4 × 33.7mm.

Nokoko%204%20port%20usb%20charger%20%231%20230V%20load%20sweep

The output on a port is 2.3A

Nokoko%204%20port%20usb%20charger%20%234%20230V%20load%20sweep

Another port is the same.

Nokoko%204%20port%20usb%20charger%20230V%20load%20sweep

All ports in parallel is also 2.3A, not the rated 5.1A

Nokoko%204%20port%20usb%20charger%20120V%20load%20sweep

Using 120VAC do not change much.

Nokoko%204%20port%20usb%20charger%20230V%20load%20test

I did the load test at 2.2A and the charger could sustain that for one hour.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5896

M1: 67.1°C, HS1: 68.9°C
HS1: The main heat producer is the transformer

Temp5897

M1: 51.7°C, M2: 42.9°C, HS1: 57.9°C

Temp5898

HS1: 48.8°C

Temp5899

HS1: 68.1°C

Temp5900

M1: 60.9°C, HS1: 67.1°C

10ohm

Noise at 0.5A load is: 77mV rms and 1488mVpp.

5ohm

Noise at 1A load is: 129mV rms and 2020mVpp.

2.5ohm

Noise at 2A load is: 146mV rms and 2144mVpp, the noise is very bad.

Tear down

Mounting it in my vice and whacking it with my mallet popped the lid off.

On this side is a fuse (F1), the safety capacitor (CY6) and the two leds (LED1 & LED2).
The usb connectors is mounted on a separate circuit board that only contains the connectors, nothing else (DCP coding do not required any components).

On the mains input side is a bridge rectifier (BD1) and the mains switcher (U1: Marked HC2523E), on the low volt side is a synchronous rectifier chip (U2: Marked HC3520).

The distance between mains and low volt side is about 2mm, except at the end of the slot where it is less, this is way to low.

It failed both the 2830 volt and 4242 volt between mains and low volt side, this makes it unsafe to use anywhere in the world.

Conclusion

Way less current than specified and lots of noise, in addition to poor isolation.

Stay away from this one.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

RD Electronic USB load HD35

Official specifications:

Rated operational voltage: DC 4-25.0V
Max discharging power: 35W
Rated operational current: 0.25-5.00A (when fan don’t work, the minimum constant current is 0.05A )
Fan Speed: Large size intelligent temperature control fan, speed 8000±10%RPM
Constant current resolution:±1% +3 digits
Heat dispatch method: intelligent temperature control fan + All aluminum fan
Working temperature: -10°C ~ 40°C
Adjustable potentiometer: Precision multiloop adjustable potentiometer
Display mode: 4 digit LED tube
Expansion port: Micro USB port, Type-C port
Trigger support: QC2.0 (QC2.0 5V, 9V, 12V and 20V), QC3.0, Huawei FCP, Samsung AFC 9V

I got it from Aliexpress dealer: RD official store

I got it in the usual Styrofoam box (That is RD’s standard packing) together with some other stuff, inside the box it was in a transparent plastic box.

At one end is the 3 buttons (One below the circuit board), the current adjustment, the display and 3 leds for fast charge protocol.

At the other end is the 3 usb connectors (Micro, A and C), between is the heatsink and fan.

I will take a closer look at the circuit further down.

Display with current, the value will flash when load is off.
Load can be configured to automatic turn on when power is applied.

Power.

Voltage.

Over Power Protection, this will show when calculated power is above 25W, the load will not not turn on.
In can be configured to automatic turn on when load is 25W or lower.

Over Voltage Protection, this happens between 25V and 30V

Auto trigger mode, it will scan for the supported protocols.

Here it shows QC3.0 and QC2.0 is found on the leds.

Here QC2.0 12V is selected, the minus sign shows it is a Quick Charge. When a fast charge trigger is active that led will flash, I took the picture when it was on.
The user interface for testing and activating the triggers is not the best, but it works.

Load testing

Current resolution is 0.01A
Voltage resolution is 0.1V
Power resolution is 0.1W
Internally current is adjusted in 0.01A steps, it is not analog!
Load is rated to handle 30V before being damaged, load shows OUP between 25V and 30V
Current adjustment range is from 0.00A to 5.09A, but supported range is from 0.05A to 5.00A
The load has USB-A, micro usb and USB-C connectors, all in parallel.
USB-C connector will not turn USB-C output on!
The support for QC3 only goes down to 4.1V.
Load can store a fast charge state and automatic activate it when powered (Vere nice for testing).
Voltage display shows voltage at input, any voltage drop is due to connector and cable resistance.
I got about 0.11V drop for connection and other resistance in usb load at 5A (Current in on A, check on C).
Current change during 60 minutes with 1.4A load at 24.9V is 0.01A, i.e. 0.6%
Current change during 60 minutes with 5A load at 6.9V is 0.003A, i.e. 0.06%
The adjustment is a multiturn potentiometer and the display will show the selected current.
The fan is audible, but not loud, it starts and stops as required (This is a bit annoying).
Current when off is about 10mA for the electronic and display.

Both current and voltage readout has good precision, but at 5A it is slightly outside specifications.

Electronic%20load%20RD%20HD35

Here is a trace with adjustment in minimum position and low current traces. The load has an offset of some mA at these low currents.
The fan started shortly in the 0.1A trace and it uses more than 0.1A

Electronic%20load%20RD%20HD35%20load%20test

Electronic%20load%20RD%20HD35%20load%20test

I tried two 1 hour test, one at maximum voltage (I used 24.9V and 1.4A) and one at maximum current (I used 6.9V and 5A).

Temp6025

M1: 43.1°C, M2: 47.3°C, HS1: 56.1°C

First set of thermo photos is from 24.9V 1.4A test

Temp6026

M1: 62.2°C, HS1: 68.8°C

Temp6027

M1: 83.9°C, HS1: 97.6°C
Both transistor and regulator warms up with high input voltage.

Temp6022

M1: 55.6°C, HS1: 60.2°C
Next set of thermo photos is from 6.9V 5A test

Temp6023

HS1: 68.5°C

Temp6024

M1: 101.9°C, M2: 67.1°C, HS1: 108.4°C
With lower input voltage the transistor must handle all the power and gets a bit warmer, the shunt resistor do also get warm at 5A

A look at the circuit

The transistor (TIP122) is the load element, it uses a resistor (R6: 0.025ohm) to sense the current. The fan is a 5V version and has its own regulator (LM317), at high input voltage it must handle some power. Turning the fan on/off is handled by a small transistor (Q2), the temperature sensor is very close to the TIP122 transistor and is a NTC (RT1) that is connected to the MPU.
The electronic has its own voltage regulators (U6: M5350B 5V, U0:5333B 3.3V). The control of the load current is done with some OpAmps (U2: Marked 324 / MZF5827). The brain in the circuit is a 8051 microprocessor (U1: N76E003AT20 18KB Flash, 1k RAM, 12 bit ADC). For the display a special controller IC (TM1650) is used.

Why 4 OpAmp, a load only needs one OpAmp. A look at the circuit shows some filters connected to the MPU on U7. One filter is R11, R12, C8 and C9, the other filter is R15, R16, C14 and C15.

0.5A

Filter input from microprocessor at 0.5A

Filter input from microprocessor at 2A

CurrentPWM

The above PWM frequency is 1kHz, is there any trace of it on the output? To test that I used my current clamp to check the load current, there is nothing in the output that look to follow the PWM (Blue trace).

Conclusion

The load works fine and with the multiturn adjustment and display it is easy to adjust. It has no problems handle the rated 35W power. It is not for low loads, the display and adjustment do not have resolution for it and it also need some minimum current to work.
It is a interesting design choice that the analog current setting is sampled by the microprocessor and then output as two PWM channels that is filtered and mixed, before being feed to the load regulation.
The fast charge trigger works fine and can current settings can be saved, this makes it ideal for testing multiple power supplies. I could have wished for a bit better user interface.
With USB-C I am missing the ability to turn outputs on (It is just a resistor), this will limit its usefulness for USB-C.

Notes

When I saved power on fast charge trigger, I could not disable the “fast charge” part again. It is not a real issue, because it is possible to update the saved trigger and for chargers without fast charge it will just work without.

The load was supplied by Rui Deng (RD) for review.

The company also has a 25W load, main difference is the fan.

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Samsung EP-TA20EWE (Fake again)

Official specifications:

Power Capacity: 9V-1.87A 5V-2.0A
Color: White
Voltage: Input:100-240V
Adaptive Fast Rapid Charger: Adaptive Fast Rapid Charger For Samsung

I got it from a ebay dealer: fongphonestore

I got it in a envelope, not in a box marked Samsung

Measurements

Power consumption when idle is 0.1 watt
Output is auto coded as QC2 with 5V, 9V and 12V
Weight: 31.9g
Size: 75.6 × 36.5 × 23.5 mm

Samsung%20EP-TA20EWE%20QC5V%20120V%20load%20sweep

The charger can deliver a lot of current on 5V with 120VAC input.

Samsung%20EP-TA20EWE%20120V%20load%20sweep

At least until I selected 12V QC, then some parts inside the charger “exploded” and the output current is dramatically reduced.

Samsung%20EP-TA20EWE%20QC9V%20230V%20load%20sweep

I got a 9V QC sweep before I tried the 12V and the overload protection do not look very good.

Because it is damaged there is no reason to run any more tests on this.

Tear down

Some pressure from my vice and I could break the lid away.

There is a fusible resistor at the input, a switcher IC with a optical feedback (U2) and a fake safety capacitor. On the low volt side is a fairly large rectifier diode and two electrolytic smoothing capacitors.

On this side is the bridge rectifier (BD1), the QC controller IC (U4: marked KTG30) and a reference (U3: 431).

At first look the circuit board looks fine enough, but a closer looks at these electrolytic capacitors shows otherwise. They are not supposed to have a black part at the bottom, this is the plug that has left the aluminium tube due to high pressure inside. The reason is over voltage, the capacitor is marked 10V and it happened when I selected QC 12V, that the capacitor was hot probably also helped to make it “exploded” faster.

The distance between mains and low volt side must be at least 4mm when there is a slot, here it is more like 2.5mm.

The charger passed the 2830 volt but failed the 4242 volt this makes it unsafe with 230V

Conclusion

A Samsung charger from Ebay, is this a real on or a fake one?
With QC, fake safety capacitor, low safety distance and capacitors that exploded I will say it is a fake.

Stay away from this charger.

Notes

This is not the first fake Samsung charger of this model I review

This charger was donated by a reader for review.

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

Koyot Dual car charger 2.4A

Official specifications:

Brand Name: KOYOT
Output Interface: USB
Type: Car Charger
USB Ports: 2
Power Source: Car Lighter Slot
Output: 5V/2.4A
Support Quick Charge Technology: USB PD
Quality Certification: CE,CCC
Model Number: C188

I got it from Aliexpress dealer: Miss shen Wonderful Store

No fancy box for this charge, just an envelope and a plastic bag.

Measurements

2.4A usb output is coded as Apple 2.1A
1A output is coded as usb charger (DCP) and Samsung.
The two usb outputs are in parallel.
Power consumption when idle is 7mA from 12V and 4mA from 24V
Weight: 23.1g
Length: 69mm
Front: ø26.1mm

The 1A output can deliver about 2.8A

Load%20sweep%2011.6V%202.4A

The 2.4A output can also deliver about 2.8A

Load%20sweep%2011.6V

And when run in parallel the maximum current is also 2.8A

Load%20sweep%2014.6V

Higher input voltage do not change it.

Voltage%20sweep%202.0A%20input%20current

The output can maintain voltage until about 7V, also note the efficiency goes down when used at 24V

No%20load%20voltage%20sweep

The chargers own current consumption varies with voltage.

Load%20test%202.4A

There was no problem running 1 hour with full load (2.4A).
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp5681

M1: 45.3°C, HS1: 50.3°C

Temp5681

M1: 45.7°C, HS1: 56.9°C

10ohm

At 0.5A the noise is 33mV rms and 170mVpp

5ohm

At 1A the noise is 39mV rms and 191mVpp

2ohm

At 2.5A the noise is 68mV rms and 269mVpp

Tear down

I could not pull or unscrew the metal and decided to cut.

The back has some heat shrink on it.

At the input is a “fuse” in the form of a 0ohm resistor, the voltage converter is a single IC (U1: marked VS2886) and it must have build in synchronous rectification (I do not see any diode).

There is no parts on this side of the circuit board.

The front circuit board has resistors for coding the two usb output, but there is also an empty space for a auto coding IC

Being a 12V device there is no need to test with high voltages.

Conclusion

This charger works, but is not perfect. The power is enough for one high power output, not for two. Why is a 2.4A output coded for 2.1A, using a auto coding chip for both outputs would have been nicer.

Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Forums:

USB Power Device Reviews

OEM Samsung fake ETA-U90EWE

Official specifications:

Avaible color: white
Dimensions: (2 × 1.38 × 0.79 )” / (51 × 35 × 20)mm (L x W x H)
Input Voltage: 100-240 V 50/60Hz 0.5A
Output Voltage: 5.0V ~ 2.0A Or 9.0V ~ 1.67A
Plug Type: US/ EU Plug for choose

I got it from ebay dealer fongphonestore

This cheap charger arrived in a envelope without any accessories.

This charger looks exactly like a Samsung charger, except the Samsung name is missing.

Measurements

Power consumption when idle is 0.16 watt
USB outputs is coded with usb charger (DCP)
Weight: 26.6g
Size: 69.4 × 36.2 × 21.4mm

OEM%20Samsung%20fake%20ETA-U90EWE%20230V%20load%20sweep

The charger can deliver about 2.4A, this is above the rating, but acceptable.

OEM%20Samsung%20fake%20ETA-U90EWE%20120V%20load%20sweep

At 120VAC the output is only 1.8A, this is below rating (Charger is rated for 100V to 240V at 2A).

OEM%20Samsung%20fake%20ETA-U90EWE%201.8A%20230V%20load%20test

OEM%20Samsung%20fake%20ETA-U90EWE%201.8A%20230V%20load%20test

A one hour test at 1.8A did not go well, it could maintain the output voltage for about 25 minutes, then it dropped to 4V and continue to deliver power.

OEM%20Samsung%20fake%20ETA-U90EWE%201.5A%20230V%20load%20test

OEM%20Samsung%20fake%20ETA-U90EWE%201.5A%20230V%20load%20test

At 1.5A the charger could maintain output for 1 hour.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp6242

M1: 75.7°C, HS1: 89.7°C

Temp6243

HS1: 75.9°C

Temp6244

M1: 72.4°C, M2: 71.7°C, HS1: 73.1°C

Temp6245

HS1: 63.3°C

Temp6246

M1: 85.5°C, HS1: 87.9°C

Temp6237

HS1: 116.4°C
At the 1.8A test the charger got considerable hotter.

10ohm

At 0.5A the noise is 126mV rms and 864mVpp.

5ohm

At 1A the noise is 137mV rms and 1094mVpp, this is on the high side.

2ohm

At 2.5A the noise is 230mV rms and 793mVpp (The charger is overloaded here).

Tear down

Some pressure with my vice and the lid popped off.

At the input is a fuse, the switcher IC is unmarked. On the other side of the transformer is a fake safe capacitor (1kV type) and a large rectifier diode. There is also a opto coupler, but the placement do not look safe (Half of it is supposed to be at the low volt side with long distance to mains voltages).

On this side of the circuit board is a bridge rectifier, a few resistors and a single capacitor.

Between the red (Mains) and the blue (Low volt side) is supposed to be above 6mm, here it is below 1mm, this is very bad.

Testing with 2830 volt and 4242 volt between mains and low volt side both failed, this means the charger is unsafe anywhere in the world.

Conclusion

This charger is a dead trap, stay away.

Notes

The charger was supplied by a reader for review.

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?

—

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Test/review of RD Electronic USB load LD35

Test/review of Samsung EP-TA20EWE (Fake)

Test/review of Coosa 5 Port USB Type C PD 72 W Charger PDS75-4UT01

Test/review of Urant USB-C PD 45W car

Test/review of YZXStudio USB meter ZY1280

3250mAh Mi Power Bank Flashlight - English Packaging!

Test/review of Dual USB Wall charger Keke-F5

Test/review of UNI-T UT658 USB tester

Test/review of GUSGU Dual USB Charger LED Display LQ-008

Test/review of Baseus Dual car charger C8-K

Test/review of RD USB Meter TC64

Test/review of Anker PowerPort Speed 5 2xQC3 A2054

Test/review of RD USB Meter AT34

Test/review of Xedain 4 port QC usb charger KeKe-QC-4

Test/review of Koyot Dual car charger 2.4A

Test/review of Nokoko 4 port usb charger

Test/review of RD Electronic USB load HD35

Test/review of Samsung EP-TA20EWE (Fake again)

Test/review of Koyot Dual car charger 2.4A

Test/review of OEM Samsung fake ETA-U90EWE