Touch IC – Resurgent Semiconductor MPR121

Audio output – 15mW into 32Ω via 3.5mm stereo socket

Input voltage – 3.3V (via 40-way Raspberry Pi GPIO connector)

Input current – 17mA idle, 36mA with all features in concurrent use.

Capacitive touch electrodes – 12 (of which 8 can be configured as 3.3V digital I/O)

Digital I/O Pins – 7, brought out from 40-way Raspberry Pi GPIO connector – pins 12, 13, 15, 16, 18, 22, 36

Push switch – active low momentary push switch connected to pin 7 on the 40-way Raspberry Pi GPIO connector (requires the Pi's onboard pullup resistor to be enabled in software)

Active low, red connected to J8.31 (5mA when on), green to J8.29 (1mA when on), blue to J8.37 (4mA when on)

Prototyping area – 84 pads (7 x 12) with 1mm diameter drills spaced 2.54mm apart.

Dimensions – 85mm x 40mm x 7mm