SN74AHC14: About Latch up

ttd

Mastermind 8640 points

Part Number: SN74AHC14
Other Parts Discussed in Thread: SN74HCS125

Tool/software:

Dear Technical Support Team,

The data sheets for the SN74AHC14 and SN74LV125APWR describe that "Latch-Up Performance Exceeds 250 mA Per JESD 17".

However, the SN74HCS125 datasheet does not.

Also, the Texas Instruments Qualification Summary for the SN74HCS125 describes that it passes at JESD 78 for latch-up.

I have a question about the latch-up performance of logic ICs.

I think the test methods are different between JESD17 and JESD78.

Is it possible to compare the latch-up performance(resistance) of SN74LV125APWR and SN74HCS125?

I think JESD78 is the test result at 100mA.
Is the SN74LV125APWR performance verified at 250mA and
the SN74HCS125 at 100mA?

Is there any difference in the actual latch-up performance(resistance) between SN74LV125APWR and SN74HCS125?

JESD17 and JESD78 have different test methods.
Can you give me your opinion on the impact on performance(resistance ) evaluation when evaluated by different test methods?

Best Regards,

ttd

7 months ago

0 Clemens Ladisch 7 months ago

Guru 317500 points

JESD17 is outdated and no longer available. Fore more details about JESD78, see the Latch-Up White Paper.

All devices have negative clamping diodes; HCS devices also have positive clamping diodes at the inputs. For AHC and LV devices, it is not possible to inject a positive current into the inputs. For all these devices, injecting a current into an input is likely to burn out the protection diode before latch-up happens. In any case, staying inside the absolute maximum ratings guarantees that latch-up does not happen.