An application note describing how Vishay 92 series optocouplers provide safety, noise and current isolation in vehicle chargers and battery monitoring systems.
This application note explains the role of Vishay 92 series optocouplers in automotive charging and battery‑monitoring systems. It covers safety isolation, noise isolation, and current isolation, showing how the devices protect high‑voltage sections while allowing low‑power microcontroller interfaces.
Two example architectures are presented: a vehicle‑mounted charger that isolates the AC mains from the high‑voltage battery, and a battery‑monitoring system that uses optocouplers to transmit voltage, health and temperature data across isolation barriers. Specific Vishay part numbers such as VOMA617A and YOMA618A are highlighted with their low‑drive‑current characteristics. This manual is written in Chinese.
| Typical forward current (IF) | 1 mA |
|---|---|
| Input drive current (VOMA617A) | 5 mA |
| Working voltage (VOMA617A) | > 700 V |
| Isolation voltage | > 400 V |
They use a low forward current of about 1 mA, which allows direct driving by microcontrollers without extra driver stages.
The VOMA617A model is recommended; it has a 5 mA low input drive current and a working voltage greater than 700 V.
The devices provide high isolation, typically greater than 400 V, suitable for protecting users from high‑voltage battery systems.