One Channel Relay Module

Here is the schematic and details for creating one channel relay module. It would be capable of driving both DC and AC current when appropriate relay is used. We can connect output pin of most of microcontrollers including Arduino to control it. Components Required 817 Optocoupler 470Ω Resistor - 2 nos. 2N2222 Transistor 1N4148 Diode 5V Relay (SRD-05VDC-SL-C) Schematic One channel relay module schematic