SN74HC595: SN74HC595 tpd test timing error

Hi  raj

This is a production block issue, could you help it? Thanks

-Thomas

Hi Thomas,

Tpd of 5.8nS is much less than the typical value here, which is a good thing. Wondering why this should cause production stop issue. Can you explain what is the customer side issue? 

Sanatan

They need to ensure this is right device, as the next stage need to have exact timing.   it seems that SN74AHC595 have the right behavior(tpd timing), please check:

1) Whether the test waveform is expected

2) The test requirement for load capacitance is 50pF, is below test method right:

Ladisch,

Thanks for info, so the typical characteristics is decided by new die, right? Do we have plan to change typical value in datasheet or mark something?

-Tomas

We are replacing 74HC595PW, and its typical timing is 16ns, customer want to keep this timing to ensure next stage sample time is enough 

Do we have chip/die can keep datasheet typical timing?

With the switch to 300 mm wafers, TI changed pretty much all logic devices.

The '595 is designed to work correctly in the usual cascading circuit. Is there a specific reason why the timing would be critical, e.g., a very long SRCLK line?