wierd lamp driver.

206

01:58:06

funny story, found this in a little tv of mine that had died, this was the backlight inverter, Is it a royer oscillator or what kind of driver is this?

I wonder why it doesnt have 2 resistors. (and yes it only had one)

published 3 years ago

SuperFaradCapacitor

3 years ago

It's not a royer oscillator because it has a tank capacitor. I would say it's a cross between a royer, a ZVS, and that simple oscillator you can find in a joule thief or arc lighter.

tooshy

3 years ago

thank you!

tooshy

3 years ago

Now all i need to know is why the tank cap on feedback coil and not on primary?

tooshy

3 years ago

But why was it used as backlight inverter

tooshy

3 years ago

waveform isnt symetric, so it would cause mercury migration.

SuperFaradCapacitor

3 years ago

The tank cap and primary coil form an oscillator that causes the transistors to push current through the main transformer at The resonant frequency of the tank circuit, which feeds the tank circuit, and causes it to keep oscillating. EC's ideal components may cause it to not act how it does in real life.

tooshy

3 years ago

K so that solves the asymmetrical waveform problem.

SuperFaradCapacitor

3 years ago

Actually it's very similar to a variation of the royer known as a baxandall converter.

tooshy

3 years ago

Interesting, Just checked the schematic of said bandaxall converter, and it has the same strange capacitor on the output i had found on the ccfl ground side. Very Interesting.

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