name: HT680 function: 3**18 Series of Encoders package: DIP/SOP18,18 manufacturer: Holtek +--()--+ AD11 | 1 18| VDD AD12 | 2 17| A9 AD14 | 3 16| A8 AD15 | 4 15| A7 DOUT | 5 14| A6 TE | 6 13| A3 OSC2 | 7 12| A2 OSC1 | 8 11| A1 VSS | 9 10| A0 +------+ This pinout came from the Chipdir: http://www.chipdir.org/