we are using the MMPF0100 PMIC (MMPF0100F0AEP) to drive a i.MX6 Dual SoC board. Our design has a Li ION Accu (not connected to the LICELL pin) that is supposed a s backup supply for a limited time.
Our goal is to detect the loss of the power-line based supply to conduct some emergency actions and switch the PMIC into the OFF state to save battery power (for the wake-up logic).
Our plan is achieve this using the transition from ON to OFF holding the PWRON low for 4 seconds.
From the state diagram of the PF0100 Figure 8. State diagram (MMPF0100 Rev. 17.0, 1/2017)
PWRON = 0 held >= 4.0 sec
All SWxOMODE bits= 0
& PWRONRSTEN = 1
(PWRON_CFG = 1)
However the available PF0100 ICs are all pre-programmed as level-triggerd PWRON (PWRON_CFG =0) and our design currently uses the level triggered PWRON to boot-up the SoC.
We now want to switch to the edge triggered mode PWRON_CFG=1 after boot-up.
Is it possible to configure the PWRON_CFG=1 bit dynamically without using fuses (or the TBB feature)?
How can we use the "PWRON low for 4 seconds tuns the PMIC OFF" feature?