12v to -12v

[wjyates]

dose anyone know of any device or circuit that can vary voltage from 12v to -12 and back

 

[MikeMl]

How much current does it have to drive? What is the load?

 

[jpanhalt]

dose anyone know of any device or circuit that can vary voltage from 12v to -12 and back

Voltage converters are quite common, such as the LT1054 and ICL7660A, but they will not give you simply a variable supply of +12 to -12 and everything in between.

What are you trying to do?

John

 

[crutschow]

Kepco makes some bipolar output power supplies but they are not common.

If the current isn't too high you could perhaps use an op amp with an output current buffer to give a variable ±12V output.

 

[wjyates]

I have a n-channel,depletion mode mosfet (ixth20n50d)
it needs neg-v to turn it off & pos-v to turn it back on
trying to see if I can make it variable

Thanks for your help
wjyates

 

[alec_t]

Depending on the on/off times you could perhaps simply drive the gate via a capacitor?