Re: Timer circuit help

From: Terry Pinnell (terrypinDELETE_at_THESEdial.pipex.com)
Date: 11/23/04 

Date: Tue, 23 Nov 2004 17:39:13 +0000

John Fields <jfields@austininstruments.com> wrote:

>Part of the 4060's oscillator circuitry is an internal inverter with
>pinned out input and output which Ken used, but which isn't available
>on the 4020. What you'd have to do then, to make an ~ equivalent
>oscillator, would be to use the spare section of the 4001 for that
>inverter, like this:
>
>
> +--[C]--+--[R]--+
> | | * |
> | [R] |
> | | |
> | B--+ |
> +--Y | B-+
> | A--+---Y
> | A-+
> | |
> | +---------+ |
> +-O|> Q(n+2)|--+
>IN>--+--A | |
> | Y-----+--|R Qn|---A
> +--B | +---------+ Y-->OUT
> +----------------B
>
>
>* I dont believe this R is needed for CMOS, and a short should work
>just as well.

Many thanks. I'll have a crack at that soon. 

-- 
Terry Pinnell
Hobbyist, West Sussex, UK

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