BUY TLP281-4 https://www.utsource.net/itm/p/11224806.html

Description: The TLP281-4 is an optically coupled isolator consisting of an infrared light-emitting diode and a NPN silicon phototransistor. Features: * Isolation voltage: 5000 Vrms * CTR: 50~400% * High speed response time: 4μs (max) * Low input current: 0.5mA (max) * Low output saturation voltage: 0.4V (max) Applications: * Isolation of digital signals * Isolation of power supply * Isolation of communication lines * Isolation of measurement signals (For reference only)