Latching Relay Circuit

There are situations that we need to implement latching relay action. This can be implemented by connecting the relay pins to proper configuration with respect to the button and the power source. In this blog post, I will present the circuit/schematic and demo video simulation of a latching relay.

Here is the schematic:

The components in this circuit are:

1. 1 latching switch --> serves as the reset

2. 1 normally open switch --> acts as the trigger button

3. 1 diode(1n4001) --> snubber diode against kick voltage

4. 1 spdt 5v relay

5. 1 LED --> serves as the load

6. 1 330 ohm resistor --> current limiting

**The power source is operating in 5volts.

The circuit can also be triggered by logic ICs(TTL/CMOS) using proper interfacing method. I usually use another relay that serve as the trigger button when interfacing ICs to latching relay circuit.

Here is the demo video: