CNY74-4 Quad optocouplers. +----------+ 1A |1 +--+ 16| 1E 1K |2 15| 1C 2K |3 14| 2C 2A |4 CNY 13| 2E 3A |5 74-4 12| 3E 3K |6 11| 3C 4K |7 10| 4C 4A |8 9| 4E +----------+ [This information is part of the GIICM]