Looking for switching supply with 110V AC in and about 400V DC out

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A user is seeking a compact offline switching power supply that outputs 400V DC at 200mA, emphasizing the need for isolation from the AC mains. Suggestions include various manufacturers and products, but many options are either too large, expensive, or not isolated. The discussion also touches on DIY solutions, such as modifying existing power supplies or designing transformers, with some users sharing schematics and component recommendations. The conversation highlights the challenges of transformer design and the desire for cost-effective solutions under $100. Overall, the thread reflects a mix of product inquiries and DIY approaches for achieving the desired power supply specifications.
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As the tittle, I am looking for off line switching supply of about 400VDC output. Anyone know who make this?

Thanks

Alan
 
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Thanks for the reply, I am look for a small power supply, something like 200mA 400V output only.
 
Does it have to be isolated from the mains?

American computer power supplies have a voltage doubler input which produces about 350 volts across a large capacitor.
This then powers an oscillator which is transformed to lower voltages.

However, you could tap off the 350 volts if your application allowed you to do this safely.
 
Thanks for the reply. I need it to be isolated. Looks like I am going to have to learn how to design switching power supply!:cry::bugeye: I so wish I had stop and talk to my engineer those days. I just let him did all the high voltage supply designs. The electronics part is quite easy, it's the transformer, I just never design transformers before.

The only one I found is the Alcopian 400V unregulated supply. It's too big and too expensive. I just want a 200mA ACAP( as cheap as possible).

They just don't have anything over 48V! Then it jump to 1KV+!
 
yungman said:
Thanks for you input. I read over the doc quickly. I think it is not isolated. I need a true off line supply that isolate from the AC side.

Thanks

Alan
My bad - I just went by their little check box that said "isolated". I guess I could have looked at the doc. On Semi has one they are marketing as isolated as well. This may be worth looking at as well...

http://www.digikey.com/product-detail/en/NCP1606BOOSTGEVB/NCP1606BOOSTGEVBOS-ND/2337352
 
  • #10
Not sure if you prefer to make or buy.

To Buy:

http://www.home.agilent.com/agilent...ng&ckey=839427&nid=-35687.384733.00&id=839427

About $7K

To Make:

At the 80W range the typical solution is to use a PFC boost fed from the line to get a large intermediate voltage, like 500V. Then drop that down with an isolated flyback.

These data sheets give you most of what you need to design the application circuit.

http://www.irf.com/technical-info/appnotes/an-1077.pdf
http://cds.linear.com/docs/Datasheet/3748fa.pdf
 
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  • #11
es1 said:
Not sure if you prefer to make or buy.

To Buy:

http://www.home.agilent.com/agilent...ng&ckey=839427&nid=-35687.384733.00&id=839427

About $7K

To Make:

At the 80W range the typical solution is to use a PFC boost fed from the line to get a large intermediate voltage, like 500V. Then drop that down with an isolated flyback.

These data sheets give you most of what you need to design the application circuit.

http://www.irf.com/technical-info/appnotes/an-1077.pdf
http://cds.linear.com/docs/Datasheet/3748fa.pdf

Thanks

I see the LT is an isolated design. I'll read up on this. Thanks for your info. I want to make it under $100! Yes I am cheap...very cheap!

Alan
 
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  • #12
Yes I am cheap...very cheap!
ditto


400V 200ma ,, only 80 watts?

is there enough room in a PC 200 watt supply to remove one or more of the high current 5volt windings from the donut and replace them with 400 volt windings of tiny wire?
Or disconnect one and use it to energize another donut with your hv windings?
Obviously you'd not pick the one that's used for regulation feedback.

Seems to me you get a volt or two per turn on those things

Tedious, but you can't beat that for cheap.

you'll need fast high voltage rectifiers... i am not fluent in those.
 
  • #13
jim hardy said:
ditto400V 200ma ,, only 80 watts?

is there enough room in a PC 200 watt supply to remove one or more of the high current 5volt windings from the donut and replace them with 400 volt windings of tiny wire?
Or disconnect one and use it to energize another donut with your hv windings?
Obviously you'd not pick the one that's used for regulation feedback.

Seems to me you get a volt or two per turn on those things

Tedious, but you can't beat that for cheap.

you'll need fast high voltage rectifiers... i am not fluent in those.

You read my mind. My problem actually is on designing the transformer. I never once in my life design a transformer. I talked a lot with my former engineer that design all the HV switchers, he talked a lot on the core material, maximum volts per turn. Problem we had a fall out!

Rectifier is not too bad, I did involved in all phase of the switcher design on and off except the transformer. I am thinking about getting a LV off line supply like you suggested, get one I can find the schematic and do it.
 
  • #14
Do you need a fast transient response and/or efficiency? If not I know how I would do it for cheap.

Get a 1:1 isolating transformer from digikey.

Follow it with a rectifying quad multiplier. Like this:
http://www.coolcircuit.com/circuit/voltage/

With 110Vac you should get a lousy 600Vdc if you size the caps right.

Use a high voltage heat sinked FET (maybe put a high power resistor in series with the FET to share some power) and a high voltage zener plus resistor to make a lousy LDO to ~415V. Since you are just building one you can trim it with a pot. The trick will be to survive the turn on transient but this should be easy with a well placed feed forward cap.

Use a floating LM371T to drop out the remaining 15V and get the 400V output. This stage can also be trimmed with a pot.

I am sure this would come in under $100 and it would be super easy to solder together in an afternoon. Much easier to debug than a SMPS too.
 
  • #15
Yungman

among the debirs on my hard drive was an appnote for this TI IC

UCC28517 EVM

document number is SLUU117C − September 2002 − Revised July 2003

1 Introduction
The UCC28517 module is a 100-W offline ac-to-dc voltage converter with power factor correction (PFC). The
prototype was designed to show how the UCC28517 could be configured to control two dc-regulated outputs
offline with one control integrated circuit. The module was design to operate over a universal input range of 85
V to 265 V with two dc regulated outputs. Output B is a 12-V, 8-W regulated output intended to be used as a
bias supply and output A is a 385-V, 100-W regulated output.

has partslist including the inductor and pcb layout
 
  • #16
jim hardy said:
Yungman

among the debirs on my hard drive was an appnote for this TI IC

UCC28517 EVM

document number is SLUU117C − September 2002 − Revised July 2003



has partslist including the inductor and pcb layout

Thanks, this helps. I have to study that a little first. I am looking at different option. I am debating on using switcher for my guitar amp design as a lot of rocker are at my age or older, nobody want to carry a heavy amp! There are company like Crate that came out with amp using switchers, but they had reliability issue.
 
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