I have a power board with a mix of LTM4675,76A, and 78 devices. Not all of them have dedicated FAULT and PGOOD outputs, so I hooked up my supply-enabled (green) LEDs to the RUNn pins. I thought I saw that in the case of supply OFF or a failure, the devices would pull RUNn low on their own. I also cleared bit 4 of MFR_CHAN_CONFIG Disable RUN Low. However, when I command a channel OFF, the RUN pin only stays pulsed low for ~ 1 second. Is there a configuration register change I can make so the RUNn lines stay self-asserted low until I turn ON the channel? Else, is there a dummy-fault I can create and clear only when it is time to enable the supply (perhaps in a reserved register)? I also use the RUNn being low to enable a bleed-off of unused supplies, so that's why this is an important feature.
Thanks so much!