→PiFace

IO expansion board for the →Raspberry Pi which features 8 open collector outputs, 2 relays and 8 inputs. PiFace protects the Raspberry Pi against electrical surges and can be operated with an external power supply. The outputs can deliver up to 500 mA due to internal Darlington transistors. More information on PiFace e.g. under: http://www.farnell.com/datasheets/1686131.pdf?COM=e14_RoadTest -- section "Tour of the PiFace Digital"