Blinking LED Emulates Incandescent Bulb
This is flashing LED circuit emulate the turning of incandescent lamp. The characteristic of incandescent lamp is that they can’t abruptly change the luminosity. This circuit is used to fade in and fade out the on and off state change. Here is the schematic diagram of the circuit:
The time constant of this fading is equal to the value of 2.2uF capacitor, so you can change this cap to emulate slow or fast response. The on-off rate is determined by the 3.3uF capacitor value, you can also change this cap to larger value for slower flashing rate.