Re: What is the reason for R7 in 317 regulator ?

From: Roy McCammon (rbmccammon_at_mmm.com)
Date: 08/03/04 

Date: Tue, 03 Aug 2004 16:43:08 -0500

little billy wrote:
> Hello,
>
> Does anyone know the 5A COnstant Volatge/Constant Current Regulator
> from the LM117/LM317A/LM317 regulator, it's on page 16 and is
> downloadable from
>
> http://www.national.com/ds.cgi/LM/LM117.pdf
>
> I am curious as to the reason from R7=220.
> What will happen if we put R7=0R ?

I haven't analyzed it, but I think it may be necessary
for stability. Without it, the opamp looks like it
would be driving a capacitive load. 

-- 
local optimization seldom leads to global optimization
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