There is a low current flasher consumes only a few Micro amperes
current and lights a high bright LED day and night for more than one
year. This can be used in switch boards, key stand etc to locate them
easily. Unlike other LED flashers, it uses the current from the
capacitor to light the LED. With a 9 volt battery, the LED flashes more
than one year.
IC1 is designed as a simple oscillator using only one gate. The LED is
placed in the discharge path of capacitor C1.Capacitor C1 charges
through D1 and R1 and discharges through the LED and R2. Power
consumoption depends on the values of R1 and C1. With higher values LED
shows low brightness but power consumption will be less.