[sdiy] 5V regulators

[Keith Winstanley]

In-Reply-To: <200103062034.HAA60719 at mail.geko.net.au>
Thanks for this Ken, I have only just seen the post
(been a bit behind with the lists)

I have on old 1A lab 5V supply I have stripped down and this will
be going into my next cabinet. I think It is the wise choice. Just
been looking at your web page 10 mins ago!

Thanks to eveyone else for there helpful comments too.


Keith

http://home.freeuk.net/lowpass

> 
> I've been down this track before myself. I run my VCDO 5V 
> sections from a separate 5V linear suppply capable of around 
> 1 amp as limited by the transformer. The regulators 
> themselves are well heatsinked - it's an old (1970) computer 
> power supply. Experiments with 7805s running off any of 
> the synth's higher voltage rails were not that satisfactory. 
> While it did work, it loaded down the 15V rail, and 
> generated a lot of heat (no news here!). It proved cheaper, 
> and more efficient to use a separate supply, with the added 
> advantage that no digital hash was making its way back into 
> the 15V rail. Why do I say cheaper when I obviously had to 
> add another supply? Because if I didn't add a separate 5V 
> one, I would have soon found myself needing to upgrage or 
> add another 15V one to supply my other modules.  
> 
> As for needing 500ma, that is the specified current 
> consumption of older 2716 chips. If you are using a modern 
> or CMOS variant, the current may be less.