A: Off B: On VOUT 5V. Output capability: when 12V input, it can output 3.3V2A, 5V2A, 7.3V2A, 9V1.8A. 1x Step-down module. The words A and B can be seen on the front of the PCB. If the indicator light is turned off, the input current is less than 1mA at no load.
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