What Is the 6N137? High-Speed Optocoupler: Pinout and Uses
The 6N137 is a high-speed optocoupler. With a photodiode + logic output stage it isolates digital signals up to 10 Mbps; it is used for SPI/UART/PWM isolation. Pinout DIP-8: 2 Anode, 3 Cathode, 5 GND, 6 Vo (open collector), 7 VE (enable), 8 VCC. The output needs a pull-up. It is used at speeds where slow phototransistor optocouplers (PC817/4N35) are not enough.
The 6N137 is a high-speed optocoupler. Instead of a phototransistor it uses a fast photodiode + logic output stage; it isolates digital signals up to 10 Mbps. For the concept, see what is an optocoupler.
What is the 6N137 used for?
Fast digital communication isolation: SPI/UART, encoders, PWM and high-speed signal lines. It is used where slow phototransistor optocouplers like the PC817/4N35 are not enough.
6N137 pinout (DIP-8)
| Pin | Function |
|---|---|
| 1 | NC |
| 2 | Anode (LED +) |
| 3 | Cathode (LED −) |
| 4 | NC |
| 5 | GND (output side) |
| 6 | Vo (output, open collector) |
| 7 | VE (enable) |
| 8 | VCC (output side) |
Specifications
| Parameter | Value |
|---|---|
| Type | High-speed optocoupler (logic output) |
| Speed | up to ~10 Mbps |
| Output | Open collector (pull-up required) |
| Enable | via the VE pin |
Watch out
The output is open-collector → a pull-up resistor is needed between Vo and VCC. A current-limiting resistor on the input LED and a decoupling capacitor on the output side are recommended.
Equivalents
- 6N136: a slower relative.
- HCPL-2601 / HCPL-0601: close high-speed optocouplers.
- Si8621: a digital-isolator (non-opto) alternative.
Find it in our catalog
Use the 6N137 search.