64. 24V Input Optocoupler Selection

Neha is designing an industrial controller and needs to connect a 24V digital input signal to a 3.3V MCU input safely.

To protect the controller from field-side noise, she wants to use an optocoupler.

The input side will be driven from the 24V signal through a series resistor, and the output side will send an isolated logic signal to the MCU.

She wants a through-hole DIP-4 package for easy prototyping.

Help her select a suitable transistor output optocoupler from DigiKey.

Make sure it has enough isolation voltage and works reliably in industrial temperatures.