Timing diagram of Module ON/OFF Logic question

In the carrier board reference schematic on page 13 “Module ON/OFF Logic” I’m not understanding how the latch_set pin can ever be pulled low to enable Q output. Assuming the jumper to disable auto start is not plugged in, so the module should automatically turn on when power is applied to the module.

Can anyone let me know how to latch_set pin functions?


It’s correct understanding, jumper not install, system will auto-power-on.
Short the jumper, system power on depend on BUTTON_PWR_ON* logic L.

I understand that that’s how it’s supposed to work, but I need to modify the circuit for our use case and I need to understand how the system auto-powers on. Based on the schematic the LATCH_SET would default to a 1 when power is connected but this would mean that the system would not turn on based on the truth table in the schematic. This is due to the pull-up resistor to 5V with no way to pull it to a 0 based on what I see.

Do you know how latch_set would get pulled low automatically to turn on the system?

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