Re: Generate -+5V from 12V

On Mon, 08 Jun 2009 00:11:45 -0400, "Michael A. Terrell"
<mike.terrell@xxxxxxxxxxxxx> wrote:

Jon Kirwan wrote:

On Sun, 7 Jun 2009 17:10:26 -0700, "BobW"
<nimby_GIMME_SOME_SPAM@xxxxxxxxxxxxxx> wrote:


"vic" <news@xxxxxxxxxxxxx> wrote in message
news:4a291f7d$0$696$426a74cc@xxxxxxxxxxxxxxx
Hi,

I need to generate a symmetric +/-5V supply from a single +12V supply. I
need about 150mA from the +5V side, and less than 50mA from the -5V side.

I've thought about using two 7805 in the following configuration :


Supply + ----+--------[7805]---- +5 V
| |
`-[7805]----+------ 0v
|
Supply - ---------+------------- -5V


does it make sense ? Would it be OK for the 7805 to sink current instead
of sourcing current, in the case of the 7805 in charge of the 0V supply ?

If this idea is garbage, what would be the recommended solution to this
problem ?

Thanks.

See alt.binaries.schematics.electronic for a (linear) circuit that will work
up to about 200mA on each supply with a minimum input voltage of 10.6V.

Sadly, Verizon (and other major service providers) have completely
eliminated all alt.* groups from their servers. This affects me, as
well. It may yet force me to get an extra-cost service added.

I know I've posted this link at least a dozen times. It is a read
only portal for selected binaries newsgroups.

http://www.usenet-replayer.com/

First time it got my attention. I'll give it a shot.

Thanks,
Jon
.

Relevant Pages

  • Re: Generate -+5V from 12V
    ... I've thought about using two 7805 in the following configuration: ... Verizon (and other major service providers) have completely ... I know I've posted this link at least a dozen times. ... First time it got my attention. ...
    (sci.electronics.basics)
  • Re: Generate -+5V from 12V
    ... Jon Kirwan wrote: ... I've thought about using two 7805 in the following configuration: ... Verizon (and other major service providers) have completely ...
    (sci.electronics.basics)
  • Re: Generate -+5V from 12V
    ... I've thought about using two 7805 in the following configuration: ... Would it be OK for the 7805 to sink current instead ... Verizon (and other major service providers) have completely ...
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  • Re: Generate -+5V from 12V
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    (sci.electronics.basics)
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