Product Overview
LTV-357T-B from Lite-On is a single-channel phototransistor optocoupler with CTR 130-260% @ 5mA, 3750Vrms isolation, 35V VCEO, 50mA output current. SOP-4 surface-mount. -B suffix = high CTR rank.
Working Principle
Infrared LED on input side emits light to phototransistor on output side, providing galvanic isolation. CTR (Current Transfer Ratio) determines output current for given LED current. B-rank guarantees 130-260% CTR at IF=5mA. 3750Vrms isolation between input and output.
Pin Description
| Pin | Name | Function |
|---|---|---|
| 1 | Anode | LED anode |
| 2 | Cathode | LED cathode |
| 3 | Emitter | Phototransistor emitter |
| 4 | Collector | Phototransistor collector |
Applications
- Signal isolation
- PLC I/O isolation
- Power supply feedback
- Industrial control
Alternative Models
| Mfr | Part | Notes |
|---|---|---|
| Sharp | PC817B | DIP-4 equivalent |
| Vishay | SFH615A-3 | Similar CTR |