ledapplications

LED Applications

A few ways to use Light Emitting Diodes

Nearly everyone knows that LEDs (Light Emitting Diodes) emit light, but they have other uses as well. This page is intended to show some of those "other" uses.

• Voltage Regulators: Most LEDs have a forward voltage breakdown of around 1.7 to 3.4 volts. You can series up LEDs to serve as Zener diodes of almost any voltage level.
• Opto-Isolators: An LED in close proximity with a photo transistor can be used to provide DC and AC isolation between two circuits. Increases in light from an LED falling on the optical input of a photo-transistor allows signal transfer via purely optical means.
• G0UPL has performed tests on many types of diodes, including LEDs, for use as Varicaps (Voltage Variable Capacitors). Check out his web page to see the results: G0UPL on LED Varicaps
• and some more from Hans G0UPL is at 5mm Red Led Varicaps.

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And here you can see a Red LED being used as a Varicap (Voltage Variable Capacitor) to tune the VFO in a Huff and Puff Stabilizer circuit.

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