In this project, when power is supplied to the touch switch circuit, the devices connected to it remain ideal as voltage at pin2 is zero. When the switch is turned ON, trigger pin (pin2) receives trigger signal. The output pin (pin 3) receives a high output due to which transistor gets turned ON. Simultaneously relay connected to it also receives high signal due to this the device connected to it gets turned ON. Voltage at pin6 should be zero at this stage. When the switch is turned OFF similar action takes place. In this type of switches, relays are latched ON with push of a button and with another push, latch is released. The working is similar to flip flop.
Filed Under: 555 Timers, Electronic Projects