Edge-Triggered S-R Flip-Flop

[Tom Del Rosso]

Jim Thompson wrote:

Ah, yes! MC4044, I remember it well... I described what an ideal
edge-matching phase detector would do and Ron Treadway conceived the
logic... first day was 360 gates, second day was 90, and on the third
day it was NINE! Then I designed and coined the phrase "charge-pump".

Now it's 8, and only 2 inputs each. Although I don't know if his
still has an advantage. AFAICS whenever you have 2 async inputs
competing with each other, it's impossible to eliminate all races.

 

[Tom Del Rosso]

Jim Thompson wrote:

I just invented a method that avoids the "delay-game"... I'll post
it tomorrow... it's time now for Cab/Merlot blend and a filet ;-)

Where is that Jim?


RSN!
[attachment in abse]

How is that less "racy" than either of my circuits? I take it on faith
that my first circuit has a bad race condition, but as I see it the race
is between, on one side, the pair of cross-coupled gates at the output
of one FF, and on the other side, everything else. As long as the pair
complete latching their outputs to a reset state then they are ready for
the reset to be removed. It looks to me like the outcome of the race is
always predictable.

Now with your new circuit it's the same concept -- the cross-coupled
gates on the first side of the race are the two on the right. They have
to latch before the D FF gets cleared.

 

[Rich Grise]

I never metastable I didn't like. ;-}

Cheers!
Rich

Keith R. Williams wrote:

In article <cf32mvg03t207se8iftt0nst3ghj52d3uf@4ax.com>,
james.meyer22@verizon.net says...

On Wed, 10 Sep 2003 23:02:56 -0400, Keith R. Williams <krw@attglobal.net> wroth:


In article <rgmvlvgfg45o5v8fftj1cnvsvn3aiqk74a@4ax.com>, Jim-T@golana-will-get-you.com says...

I just invented a method that avoids the "delay-game"... I'll post it
tomorrow... it's time now for Cab/Merlot blend and a filet ;-)

Does it get rid of metastability too? ;-)

I find that the more I drink, the stabler I get. Sometimes I get so
stable I can hardly stand up.


Sometimes I'm (meta) stable on the bar stool. I could fall into
the potential well on the right, or the left (both stable
conditions). ...but I'm (meta) stable sitting on the local
maximum inbetween.

--
To send an email that will actually get read, elide 'ard'.

 

[Keith R. Williams]

In article <3f6c77ed$0$35530$a32e20b9@news.nntpservers.com>,
richardgrise@yahoo.com says...

I never metastable I didn't like. ;-}

You sleep there?

--
Keith

Cheers!
Rich

Keith R. Williams wrote:
In article <cf32mvg03t207se8iftt0nst3ghj52d3uf@4ax.com>,
james.meyer22@verizon.net says...

On Wed, 10 Sep 2003 23:02:56 -0400, Keith R. Williams <krw@attglobal.net> wroth:


In article <rgmvlvgfg45o5v8fftj1cnvsvn3aiqk74a@4ax.com>, Jim-T@golana-will-get-you.com says...

I just invented a method that avoids the "delay-game"... I'll post it
tomorrow... it's time now for Cab/Merlot blend and a filet ;-)

Does it get rid of metastability too? ;-)

I find that the more I drink, the stabler I get. Sometimes I get so
stable I can hardly stand up.


Sometimes I'm (meta) stable on the bar stool. I could fall into
the potential well on the right, or the left (both stable
conditions). ...but I'm (meta) stable sitting on the local
maximum inbetween.