UUGear Witty Pi 3 User Manual

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The signal should be a positive pulse, and the pulse length should be longer than 300ms. Processing a
pulse will be equal to taping the switch once, so it will turn on your Raspberry Pi if your Pi is off, or
turn off your Raspberry Pi if your Pi is on.
CATHOD
It is the cathode for Raspberry Pi. There is a 0.05 Ohm sampling resistor between CATHOD and
GND, to measure the actual output current.
If you measure the voltage between cathode and ground as V
k
, you can calculate the actual current
like this:
I
out
= V
k
/ 0.05 = 20 * V
k
GND
It is the ground of Witty Pi 3 board, and it directly connects to the GND wire of power supply.

UUGear Witty Pi 3 Specifications

General

Brand	UUGear
Model	Witty Pi 3
Category	Control Unit
Language	English