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+/-20V, few hundreds mA split rail?

ee171

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dick_freebird

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Might look at the application figures and see whether
this is just a change to feedback network or is bound
up by some inherent limitations in the product.

You might prefer a good-to-go module like from Pico
or others in the low-power, medium-voltage space.

If the output is isolated then you can use two of them
and wire them to get split supply, and not have to
worry about cross-regulation as with a single controller.
 

ee171

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Might look at the application figures and see whether
this is just a change to feedback network or is bound
up by some inherent limitations in the product.

You might prefer a good-to-go module like from Pico
or others in the low-power, medium-voltage space.

If the output is isolated then you can use two of them
and wire them to get split supply, and not have to
worry about cross-regulation as with a single controller.

I think most IC will have a limitation at around 32V or so range because many IC processes are designed to support automobile or LCD devices. So it's not surprising to see many chips have a maximum voltage swing around that range.

What is Pico power module? They look like power supply for CPU.

I overstated my specs for the current requirement. My design needs around 50mA; so that is 200mW. Pico low-power PSU is hundreds of watts.
 

dick_freebird

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Might recommend using their 24V-output ones, with
LM7805/LM7905 post-regulators to get your +/-20V?

For that matter, as low as the actual mA need is, maybe
something like a self-oscillating push-pull, full wave
bridge to get about +/-24V and post-regulation with
those same linears? I forget the proper name of the
self-oscillating push-pull inverter....
 

BradtheRad

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Example of twin voltage doublers creating split supply, +20-20V. The supply is 12VAC peak.
(The 5 ohm resistor is unnecessary.)

If your supply is DC then you can place this entire layout across a full H-bridge gated to apply 12VAC.

dual voltage doublers 12VAC to split +20-20V 2 loads 400 ohm each.png
 

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