BlockingOscillatorAsBooster PUBLIC

Exploring the use of a blocking oscillator to boost the voltage of a 1.5v single cell battery - enough to drive a 2v red LED.

Popularly known as the "Joule Thief", this circuit appears to get more out of an AA battery than expected.

Persistence of vision is part of the trick: the LED is pulsed rapidly with a duty cycle of about 1:2 and the eye smoothes out the fluctuations. The average current in the LED is below the nominal DC value.

The other part of the trick is that the oscillator keeps going even when the battery voltage has dropped to 1v. This is a big benefit of booster type circuits. How low can the voltage drop before oscillation stops? Try a simulation with BAT1 voltage as a parameter!