+/- 60 to +/-20 VDC

[Hurtig]

I need some ideas for generatig +/- 20 VDC from a +/-60 VDC power supply.
The maximum current requirement is approx 200mA.

I could go for a linear regulator, but it will cause approx 16watt dissipation in the regulator.
Does anyone know a simple switcher, that can do this. I have no problem finding the positive version, but the negative seems hard to find....

[Minion]

If the Transformer has Dual secondaries as opposed to a Center tapped secondary then you can use the Positive voltage regulator for the Negitive rail , you would just use the positive as ground and ground as negitive ......

That is a lot of heat to disapate with a single regulator but you can use a pass transistor to help dissapate that heat , the regulators datasheet should show how to do this ......

You might also consider just using only half of the power transformer and do a Voltage doubler which will give you +/-30v DC that will be a lot easier to regulate down to +/-20v DC , you would need to use about double the capacitance in the PSU than before because on the increased ripple voltage from the voltage doubler .......


Cheers