PMIC_ON_REQ being held low. Won't allow PMIC to turn on.

[benjaminblanton]

I'm having issues bringing up a new board.  We are using a PF3000 PMIC and when power is applied, the PMIC_ON_REQ never goes high.  I cut the trace and pulled PMIC_ON_REQ on the PMIC high and now all my rails boot, but the IMX7 is still holding this line low on it's end and the devices seems to not turn on.

Something I noticed on this design, which I've inherited:

ONOFF: floating, but can be pulled down

TEST_MODE: Pulled hard to ground with no 100K

What am I missing?   Why isn't the IMX7 booting?

Thanks!

[igorpadykov]

Hi Benjamin

please check that VDD_SNVS_IN is provided to i.MX7D.

According to Table 10. Reset and ON/OFF recommendations Hardware Development

Guide for i.MX7Dual and 7Solo Applications Processors:

A brief connection to GND in OFF mode causes the internal power management state machine to change state to ON.

http://www.nxp.com/files/32bit/doc/user_guide/IMX7DSHDG.pdf

Note on SabreSD schematic spf-28590 p.21 C367 is connected to ONOFF (ONOFF has on-chip pullup).

Schematics (2)
Design files for i.MX 7Dual (REV D)
Design files, including hardware schematics, Gerbers, and OrCAD files for i.MX 7Dual (REV D)
http://www.nxp.com/products/microcontrollers-and-processors/arm-processors/i.mx-applications-process...

Best regards
igor
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[benjaminblanton]

Great Thanks!