SN74LV74A: set up time before CLK

Ryoma Ohashi

Part Number: SN74LV74A

Tool/software:

Hi team,

What will happen to the ouput if the input signal can not meet tus?
Will it just miss the input signal? Or will some another issue occurs?

Regards
Ohashi

+1 Clemens Ladisch 4 months ago

Guru 272490 points

The input signal might be missed, or (with low probability) the flip-flop can go into a metastable state; see Metastable Response in 5-V Logic Circuits.

0 Ryoma Ohashi 4 months ago in reply to Clemens Ladisch

Hi Clemens,

Thanks for your support.

Could you tell us how long the metastable period typically is if it enters in it?

Regards
Ohashi

0 Clemens Ladisch 4 months ago in reply to Ryoma Ohashi

Guru 272490 points

It's pretty much random.

0 Ryoma Ohashi 4 months ago in reply to Clemens Ladisch

Hi Clemens,

Thanks for your reply. Is it like few us~ms order? Or is there a possibility of taking like few sec for the recovery?

Regards
Ohashi

+1 Clemens Ladisch 4 months ago in reply to Ryoma Ohashi

Guru 272490 points

I'd guess that longer times are less likely. But there is no upper limit.

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