- 4N31T
- Fairchild Semiconductor Corporation
- 1 CHANNEL DARLINGTON OUTPUT OPTOCOUPLER
- 4N31TM
- Fairchild Semiconductor Corporation
- 1 CHANNEL DARLINGTON OUTPUT OPTOCOUPLER
- 4N31TV
- Fairchild Semiconductor Corporation
- 1 CHANNEL DARLINGTON OUTPUT OPTOCOUPLER
- 4N31TVM
- Fairchild Semiconductor Corporation
- 1 CHANNEL DARLINGTON OUTPUT OPTOCOUPLER