MX7/PF3000 ON/OFF Button and 'Power Good'

demoniacmilk — Fri, 06 Apr 2018 15:26:18 GMT

Hello community,

while developing an MX7 module for a given mainboard I ran into a few questions regarding MX7 run modes.

The mainboard provides an ON/OFF Button.
The mainboard provides 5V as the only power input
1. Power for an RTC may or may not be provided, depending on mainboard version
The mainboard signals "power good" on a pin
1. The MX7 Module may not boot if this pin is held low

If I understood correctly, the SNVS power domain will trigger the MX7 to go from OFF to RUN mode.

SNVS is powered from the LICELL input. What happens if LICELL is not used?

Is there a possibility to stop the MX7 from booting if power is applied but the ONOFF button is not pressed?

The PF3000 has no enable pin. Except for cutting power with e.g. an additional FET: is there a way to disable/enable the PMIC with a digital signal?

Re: MX7/PF3000 ON/OFF Button and 'Power Good'

guoweisun — Wed, 11 Apr 2018 07:54:00 GMT

Hi,

For PF3000 please note that VSNVS powers the low-power, SNVS/RTC domain on the processor.

It derives its power from either VIN, or coin cell, and cannot be disabled.

PF3000 has a PWRON pin has function of power ON/OFF input from processor.

For I.MX board please check PF3000 VSNVS connection way.