Re: power supply circuit

Article View: sci.electronics.basics

Article #19

Back to sci.electronics.basics Previous Next

#19

From: Bill Bowden
Date: Wed, 11 Jun 2008 06:21

22 lines
2534 bytes

On Jun 9, 5:42 am, F Murtz <hagg...@hotmail.com> wrote:
> I would like to make an adjustable power supply using a transformer with
> a 24v 5a single wound secondary I would like the voltage to be
> adjustable from lowest to highest possible given transformer I would
> like to have regulated current
>
> There is another possibility I also have a larger transformer with two
> 32v 4.7a secondaries If anyone has a schematic for an adjustable power
> supply with adjustable current regulation making the most of the
> transformer specs I would be eternally grateful

Look up the LM338 three terminal regulator. It's rated at 5 amps and
35 volts from output to input. All you need is a couple resistors or a
pot to set the output voltage. Use a 10 amp bridge rectifier to
convert the transformer secondary AC to DC and a 20,000uF, or
thereabouts filter cap. Connect the capacitor to the (+) input of the
regulator and ground and adjust the resistors for the desired output
votage. The regulator also has current limiting, but not sure what it
is. You can get 1.2 volts to maybe 24 volts DC out, but you need a
large heat sink   when the output is set low and drawing 5 amps.

-Bill

Technical Details

Message-ID: <b2bf7042-d097-4ac5-9a16-97fcc2d6e3f1@y21g2000hsf.googlegroups.com>

Path: arc1-ca.pugleaf.net!g2news1.google.com!postnews.google.com!y21g2000hsf.googlegroups.com!not-for-mail

References: <484d2532@dnews.tpgi.com.au>

Show Full Headers

Complete Article Headers

X-Google-Thread: 111d0a,5993850357c82189
X-Google-Thread: 112d1e,5993850357c82189
X-Google-Thread: 103407,5993850357c82189
X-Google-Attributes: gid111d0a,gid112d1e,gid103407,domainid0,public,usenet
X-Google-Language: ENGLISH,ASCII-7-bit
Path: arc1-ca.pugleaf.net!g2news1.google.com!postnews.google.com!y21g2000hsf.googlegroups.com!not-for-mail
From: Bill Bowden <wrongaddress@att.net>
Newsgroups: sci.electronics.basics,sci.electronics.design,aus.electronics
Subject: Re: power supply circuit
Date: Tue, 10 Jun 2008 23:21:53 -0700 (PDT)
Organization: http://groups.google.com
Lines: 22
Message-ID: <b2bf7042-d097-4ac5-9a16-97fcc2d6e3f1@y21g2000hsf.googlegroups.com>
References: <484d2532@dnews.tpgi.com.au>
NNTP-Posting-Host: 4.232.42.162
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
X-Trace: posting.google.com 1213165313 18376 127.0.0.1 (11 Jun 2008 06:21:53 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Wed, 11 Jun 2008 06:21:53 +0000 (UTC)
Complaints-To: groups-abuse@google.com
Injection-Info: y21g2000hsf.googlegroups.com; posting-host=4.232.42.162; 
 posting-account=Aao6uQkAAADZHBdEpH-MwBrBugtIJ6bC
User-Agent: G2/1.0
X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.6) 
 Gecko/20050225 Firefox/1.0.1,gzip(gfe),gzip(gfe)

Reply to Parent Message