Need 100 VDC 2-5 Amps

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Hello... I tried using the PI Design software, but kept running into various warnings and errors, so thought I'd cut to the chase on my present design challenge. I need to design an offline 115VAC to 100VDC out, with 2-5 amps Iout. I really am intriqued by PI tech because I have very little space, and hence need very small part count. Many appreciations for pointing me to the correct PI component type and suggested design topology for its implementation to get me where I need to go.

 

Just a small additional note. Design urgency is very high, and I will need to manufacturer quite a number of these units (integrated into another product), so hopefully I can get some support from a knowledeable tech person at PI as soon as possible. Thanks... 

Hi,

Could you please share the complete specications of design and the application that you are trying to design for, so that I can recommend appropriate PI device to you.

Regards,

PI-NANO

Sure... It is not too complicated:

Input: Stardard USA AC; 115VAC

Output: 90-120 VDC, with at least 2-3 amps Iout, with consideration of around 2x more (derating) due to current inrush.

Ripple: Not critical but 1-3 volts is acceptable. 

Application: Provides dc link for motor control board driving a 90 VDC motor.

 

That said, in the time frame since my last post, I designed an offline ACDC buck converter, that appears to work quite well. Only a handful of components required. Now I'm curious if PI can actually do this better and cheaper. Are you up to the challenge? :)

 

Hi,

Since you are stepping down the voltage very little, it is better to use AC/DC buck converter. Unfortunately we do not have any AC/DC buck topology device to suggest at 300W - 600W power level.

Regards,

PI-NANO

Actually with ACDC converter to work I need low voltage to power its control logic. What is a cheap low part count PI solution to get 12-15 volts from 115VAC?

 

OR... Since I first rectify 115VAC to get ~157VDC (before implement the step down converter to get this to 100VDC), I can tap off the 157VDC point to get to the 12-15 Volts (no need to rectify twice, eh).

 

Any PI solution proposals here? A bazillion thanks! 

Hi,

you can use Linkswitch-TN with simple buck configuration to power up the control circuit.

Please find the design example at following location

http://www.powerint.com/sites/default/files/PDFFiles/der47.pdf

http://www.powerint.com/en/products/linkswitch-family/linkswitch-tn

This is the simplest solution that I can think off.

Regards,

PI-NANO

That is not bad, and I appreciate the heads up... as I may consider this. However it is likely not competitive (price and PCB space) as this solution (see link below), where for a few bucks more I can get a version with more current output. See link below:  http://www.digikey.com/product-search/en?WT.z_header=search_go&lang=en&site=us&keywords=835-1105-ND&x=-1384&y=-51  Please let me know if PI has other options. Thanks...

Actually thinking this about this more, with the right xfromer in the design illustrated in Figure 5.2 (see link below), I should be able to get 100VDC 2-5 Amps, yes? Actually likely both DC output rails, 100VDC and 15VDC. Alas... It would need to be a cheap small-as-possible, off the shelf xformer. The expected sales volume is expected to be reasonable, but margins require no custom components. :(  http://www.powerint.com/sites/default/files/product-docs/lnk362-364.pdf 

Hi,

Linkswitch family device (LNK364) can deliver upto a maximum of 6W at 85VAC. But your design requires around 200W - 500W at 100V DC output. There is no way you can get 200W by using this device.

Regards,

PI-NANO

Hi,

 

Cost of Linkswitch-TN solution is way cheaper than the product that you have mentioned here. Regarding PCB space, if you do a daughter board, I think you will still be able fit it in the same space as monolithic IC.

 

If you need any design related help or costing information please contact one of our field offices in your geographical region. Our field apps people will be able to help you with that.

 

Please find our sales office information at following location.

 

http://www.powerint.com/en/company/sales-information/worldwide-sales-support-locations

 Regards,PI-NANO