Old Scanner Inverter

[sprocket]

I have the inverter and lamp from a Mustek 800 IISP scanner and I'm wanting to make it light up outside of the scanner (bench light)

It has a 3 connection plug from the main board with Red, Black and Brown
What voltages do I hook up and where.
I tried (computer power supply) 5vdc to Red and Blk Gnd and brown shorted to blk and Nada

Whats the Brown for?

I did a schematic of it attached

[b700029]

Re: Old Scanner Inverter

Brown is active-high enable. Connect it to red to enable the base drive for the switching transistors. It's a standard Royer oscillator circuit.

From the 5V cap I would guess it's supposed to run at 3.3V supply.

[sprocket]

Re: Old Scanner Inverter

Thanks b70029

I Tried 3.3 and that didn't work

The guy that gave me this junk looked around and found the original power supply for it and I couldn't believe it, the PS yellow marked 25v went to red and PS red marked 5v went to brown and PS black to black and away it went.

Unhook the brown and it does turn the light off as you said

25V, I still can't believe it ....

[b700029]

Re: Old Scanner Inverter

Are you sure that's a 5V cap? It would've blown long ago if it was really supposed to be on a 25V circuit.

[sprocket]

Re: Old Scanner Inverter

I could have read it wrong, kinda tight peeking by the side of it. May have been 25v and I didn't see the 2.
Anyway it's the original I guess and probably been there since day one and it's totally buried now in a new case I put it in.

Thanks again for the heads up

[999999999]

Re: Old Scanner Inverter

10uF cap is very unlikely to be only 5V. Maybe a small chance if it's a tantalum cap but not at all likely otherwise.