12 in 1 USB Tester Voltage Current Meter

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Official specifications: I bought this from Aliexpress dealer HATCRPin Store

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I got it in a plastic bag in a plastic envelope, without any instructions.

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It has a single button for user interface, clicking on it will change screen.

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Display and functions

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Power on welcome screen.

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Standard display with voltage, current, power, capacity, energy, time and internal temperature.
Double click will reset Wh, triple click will reset time, holding down button will reset mAh

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Another readout with less information.

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Here voltage on the data pins is shown, this can be used to guess some fast charge schemes. It also shows the resistance of the load.

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The backlight adjustment screen, if can be adjusted from off, 1-59s and on. Off means it goes off immediately and makes it fairly hard to use the meter.
Double clicks will increase the value, triple clicks will decrease the reading, holding the button down on the last click will make it auto repeat.



Measurements

Measurements are done on usb port.

Voltage

The meter do not like low voltage, it will show wrong results.

Current

The current do not work at low value, but the precision is good when the voltage is 5V or higher.
Temp6900

M1: 60.1C, HS1: 96.5C
The resistor gets very hot at 5A, but then 5A is also too much for regular USB connectors, they are rated for maximum 3A

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The display is affected by the heat. The temperature sensor to not measure the resistor, but is probably inside the microprocessor.



Tear down

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I could just pull it apart.

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The circuit is very simple with a microprocessor and a voltage regulator (M5336B)

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The series resistor and the button are on this side.

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Conclusion

This is a simple USB meter, but it do the job with both capacity and energy measurements, the heat at 5A is a minor problem, correctly working USB equipment will not draw above 3A.
Except voltage and current on some screens the text is on the small side.



Notes

How do I make the test