Re: 1Mhz -> 1hz


theJackal wrote:
> On Tue, 20 Dec 2005 11:44:23 -0500, John Popelish <jpopelish@xxxxxxxx>
> wrote:
>
> >theJackal wrote:
> >> On Mon, 19 Dec 2005 06:42:58 -0600, "siva" <a.siva@xxxxxxxxx> wrote:
> >>
> >>
> >>>Hi,
> >>>to convert the 1 mhz input to 1 hz output, how many no. of D-flip flops
> >>>should i use?
> >>>Thanks
> >>>regards
> >>>siva
> >>>
> >>
> >>
> >> Somebody said 20,21 flipflops .. naw you can use much less . A
> >> typical divide by 10 counter has 4flipflops and so If you don't feel
> >> like cracking your brains get 3 divide by 10 counters , cascade them
> >> and you got your 1pulse/sec signal.
> >> If you want to design the thing let me know
> >
> >3 divide by 10 counters gets 1 MHz down to 1kHz.
> >
> >6 divide by 10 counters gets you to 1 Hz, with 24 flip flops.
>
>
> Yes . Its been a busy day on Mixer theory here ... LOL
>
> It seems the limit is log10^6/ log12 *4 = 22 flip flops

Not right.

2^20=1,048,576 - I've recommended using 21 D-type bistables so that you
can use one more D-type to stretch the reset pulse out to 1usec.

----------------
Bill Sloman, Nijmegen

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