UsbAmps - revision BUsbAmps is a small USB pass-through device that measures current, voltage and power used by whatever is connected on its output.

By default it shows current value but you can also recall minimum and maximum. Latest revision (C) also allows special high-power mode where it behaves as an USB charging port.

Source files and other details can be found at GitHub.

UsbAmps schematics

Usage guide is available on YouTube:

You can also check quick YouTube review by David Jones:

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