8 Opto-isolated Relay board
This is a 8 channel relay interface board using ULN2803. All the relays are opto-isolated using optocouplers and can be controlled directly using a microcontroller of any kind (Arduino , 8051, AVR, PIC, DSP, ARM, ARM, MSP430, TTL logic) or a PC.
This is a 8 channel relay interface board using ULN2803. All the relays are opto-isolated using optocouplers and can be controlled directly using a microcontroller of any kind (Arduino , 8051, AVR, PIC, DSP, ARM, ARM, MSP430, TTL logic) or a PC.
It’s easy to manufacture and have three pin screw terminals for easy connectivity.
Schematic
The full schematic is shown below
Photos
What is the capacitance of c2?
You can use a small -non polarized capacitor like 10nF