Quad Optoisolator for 3.3V 5V Logic Control

A 4-channel optoisolator module designed specifically to extend the reach of 3.3 V and 5 V logic systems into higher-voltage domains. Mechanical footprint: 53 × 27 × 15 mm; approximate mass: 12 g. Input compatibility: native support for 3.3 V and 5 V TTL/CMOS logic levels, with operational headroom from 3.6 V to 24 V. Output side handles 3.6 V to 30 V loads at up to 10 mA per channel. Power delivery is governed by a constant-power constraint — meaning available current scales down linearly as output voltage rises, ensuring safe operation without external current limiting. Built with PC817 optocouplers and standard PCB construction for durability and repeatable performance. Each channel operates as a standalone optically isolated switch: control-side activation closes the output-side circuit. No polarity inversion, no delay compensation needed — just deterministic, cycle-accurate switching suitable for timing-critical sequences like stepper motor phase control or sequential valve actuation. Compatible with popular development platforms including Arduino UNO/Nano, Raspberry Pi, STM32 Nucleo, and ESP32 DevKit. Typical deployments include educational robotics kits, benchtop power supply sequencers, HVAC zone controllers, and IoT edge devices managing local 24 V lighting or pump circuits — always prioritising signal integrity, user safety, and long-term stability over raw speed or bandwidth.