There are numerous circuits for digital ON/OFF switch. Using few components and a CMOS LOGIC IC, two digital switches can be constructed. This circuit turns ON or drives an output into logic 1 (approximately equal to the power supply voltage, +VDD) when pressing a push button. It turns OFF or drives an output into logic O (equal to the GND or O Volts) when the same key is pressed again. The operation will toggle ON or OFF alternately.
Applications: Push-button for digital applications, Soft-touch digital switches, click-less electronic controller, control circuits, digital counters.