MOSFET-based Joule Thief steps up voltage

The output will be pulses of voltage that can be filtered using a diode and capacitor. As there is no regulation, the output voltage will vary with the input voltage or load. As this circuit uses a BJT, the supply voltage needs to be at least 0.7V to work, and with enhancement-mode MOSFETs, the supply voltage must usually be even higher. In this Design Idea, a low-threshold MOSFET (Q1) is used with coupled ...

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Joule Thief Low Voltage Battery Charger

A "Joule Thief" is a simple voltage booster circuit. It can increase the voltage of power source by changing the constant low voltage signal into a series of rapid pulses at a higher voltage. You most commonly see this kind of circuit used to power LEDs with a "dead" battery. But there are many more potential applications for this kind of circuit. In this project, I am going to show you how you can use a Jo ...

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