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Anonymous Poster

Stepdown Voltage

06/18/2009 10:49 AM

how to step down 220v ac to 5v dc supply with out a transformer?

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Guru
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#1

Re: step down ac supply

06/18/2009 10:57 AM

Rectify, then voltage-regulate. It will be less efficient than a transformer, so those components are going to need to survive cooking.

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#2

Re: step down ac supply

06/18/2009 11:11 AM

The MAX5022 evaluation kit (EV kit) is a fully assembled and tested 5W flyback converter circuit board. The power supply is configured for an isolated +5VDC output voltage that can supply up to 1A of current. The line input voltage range is from 85VAC to 265VAC or 120VDC to 375VDC.

Check out this link http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3011/t/al

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#3

Re: Step down Voltage

06/18/2009 7:20 PM

It depends on how much current you require, but the short answer is you want either a switch mode power supply or a linear regulator with a full bridge diode rectifier. Try a google search of the above terms for much more information.

What's the application (how much current and how smooth an output do you require)? What are you trying to power?

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#4

Re: Stepdown Voltage

06/18/2009 8:32 PM

Just buy some power regulator that take input 220V and output 5 volts. There is a lot of these voltage regulator available in the market.

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#5

Re: Stepdown Voltage

06/18/2009 10:07 PM

When an Edgar asks a question which pre-empts the obvious and efficient (transformer+diode bridge here)

The answer is obvious - it is homework.

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#6
In reply to #5

Re: Stepdown Voltage

06/18/2009 10:14 PM

I do agree with you, Guru. It is a homework.

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