ADM1272 /RESTART

Hi ADI Expert

I have seen the following description in the ADM1272 datasheet: Does this mean that the GPIO1/2 can be used to get an adjustable restart time function?

The restart function can also be triggered from a PMBus command. In all cases, the restart time can be programmed from 2 sec to 25 sec on the PMBus, but defaults back to 10 sec after the device POR.

Thanks!!

  • +1
    •  Analog Employees 
    on Mar 4, 2021 7:07 PM 1 month ago

    Hi Chester,

        The ADM1272 has two GPIO pins, but these do not relate in any way to the RESTART function.

        The RESTART function is activated by a falling edge on the RESTART pin, or by a POWER_CYCLE PMBus command, and forces the ADM1272 to turn off the FET and delay for the programmed time before turning on again. This delay value defaults to 10s, but can be changed by a PMBus write to the RESTART_TIME register (0xCC).

    Thanks!

      Nathan

  • Hi Nathan

    I also has one more question about ADM1272.

    since it can adj the glitch filter for severe overcurrent. but I am not sure that the normal overcurrent response time? would you please help provide this information? thanks!!!

  • 0
    •  Analog Employees 
    on Mar 10, 2021 6:39 PM 1 month ago in reply to ChesterChen

    Hi Chester,

        There are two different responses to OC: 1) analog GATE pin control to limit current at the ISET limit, and 2) EFAULT pin circuit breaker. The OC threshold engages slightly lower than the analog control response. When the OC threshold engages it starts the EFAULT pin charging up to its 1V threshold, which is a timer function. If the FET current continues increasing then the analog control loop engages to pull down GATE and limit current while the EFAULT pin is charging. All of this is analog in nature, so has speed limits. In the limit, the EFAULT pin does not act faster than 32us of when the voltage crosses the 1V EFAULT threshold.

    Thanks!

      Nathan