Stepup DC Power Supply Help

[Rileyesi]

We make power supplies that use an AC input, step down transformers, etc. Run
of the mill stuff. I've been given a task to design a dual output (one at 600
VDC 2.0 mA and one at 18,000 VDC 0.2 mA) supply with a 20 VDC input. I've
never done a project like this and need a starting point. DC-DC converters?

Thanks.

 

[Rene Tschaggelar]

We make power supplies that use an AC input, step down transformers, etc. Run
of the mill stuff. I've been given a task to design a dual output (one at 600
VDC 2.0 mA and one at 18,000 VDC 0.2 mA) supply with a 20 VDC input. I've
never done a project like this and need a starting point. DC-DC converters?

There are several manufacturers of switch mode controller chips.
The datasheets for these chips provide a whealth of information.
They also tend to have application notes.

Rene

 

[Rob]

Look at places that make xray power supplies. 600VDC would be about
right for the grid supply of an xray tube. 18Kv is a little on the low
side for the cathode supply, more like 30kv minimum. About 5W in total
for your example, so probably us a step-up transformer to a couple of
Kv, then multipliers up to 18Kv, with feedback from the final
multiplier for voltage regulation. The 600v could be done with just a
step-up transformer.

 

[Rileyesi]

I don't think I can use step up transformers because the power supply is using
a DC source, not AC, right??

 

[John Jardine]

We make power supplies that use an AC input, step down transformers, etc. Run
of the mill stuff. I've been given a task to design a dual output (one at 600
VDC 2.0 mA and one at 18,000 VDC 0.2 mA) supply with a 20 VDC input. I've
never done a project like this and need a starting point. DC-DC converters?

Thanks.

It's all in the stepup transformer and o/p multipliers.
Have a look at -any- TV set, circuit diagram.
regards
john

 

[Rob]

The transformers would be part of a inverter circuit, which operates
on your 20VDC, bit like the power inverters you can get to provide
mains voltage from 12V batteries during a power cut etc.