USB meter: Dinky



Official specifications:

• Voltage detection range: 5-12V
• Current detection range: 3A
• Size: L*W*H :70*22.5*10mm
• Color: White or Black

I found this unit on Ebay at a dealer called lakeyx101.



How does it look




The four digit display is used to show both voltage and current at the same time, this means only one digit after the point.





The box did not use any screws, I only had to pry the top off.





The resistor is a wire, not a smd component.



The trimmer is used to trim the voltage display.





Measurements



Red means flashing display

• The meter uses 10.5 mA current
• The display flashes when USB voltage is 3.7 volt or below.
• The display flashes when USB voltage is 5.8 volt or above.
• The voltage shown on the display is close to the input voltage.
• Displayed current is within 0.1A.
• Internal resistance is about 0.3ohm including connection resistance.
• USB data works fine.

M1: 47,4°C, M2: 52,6°C, HS1: 65,1°C
The resistor do get fairly hot, this is because it has a "high" resistance.



Conclusion

The usb meter has a fairly high internal resistance and the resolution is low with only one decimal place.
This usb meter works fine enough, but there are better devices.



Notes

How do I make the test