Seen here is the basic circuit for a soft-start switch, assembled on a breadboard. The circuit uses a 74HC14 (actually it is the HCT version) for the switch deboucing and to generate the power-on reset signal for the 74HC107. The main component is the 74HC107, wired as a toggle flip-flop. Connected to the non-inverting output (Q) is the base of an NPN transistor, which in turn is in series with an hi-power LED. The bi-color LED is controlled directly by both outputs (Q and /Q) of the device.
Created: June 11, 2013