Ok, so it's time to tackle the last big thing: POWER
I'm trying to and understand the [PMIC MMPF0100A](https://www.nxp.com/products/MMPF0100) . Reading through the datasheet and looking to the Sabre DualLite CPU2 card. Although, I think the I should check the imex rex
They use a now obsolete part ISL6236AIRZ "Notebook Power System Voltage Regulator". But the OpenRex does use the above PMIC
I probably need to make a list of voltages I require and figure out what to do about peripherals I don't want to power (like mipi, pcie).
The Reference Manual has 2 schematics about power.
"Simple" one has 2 DCDC converters
Table of voltages and power:
Input power:
| Name | Voltage | Current? |
| ------- | -------- | -------- |
| USB IN | 5V | 0.5A? |
| BATT IN | 3.2-4.2? | ?? |
Voltages required:
(page 523)
| Name | Notes | Voltage | Source? |
| ------------- | -------------------------------------------------------------------- | ---------------------- | ---------------------------- |
| VDDARM_IN | | 1.375V | SW1AB |
| VDDSOC_IN | | 1.375V | SW1C |
| VDDHIGH_IN | | 3V | SW2 |
| NVCC_LVDS_2P5 | Do I need LVDS? "should<br>be connected directly to<br>VDD_HIGH_CAP" | | |
| NVCC_DRAM | | 1.35 if DDR3L | |
| NVCC_RGMII | for 1GB ethernet | 1.5? | |
| NVCC_GPIO | buttons | | |
| NVCC_ENET | for 100MB ethernet? | | |
| NVCC_EIM0 | all EIM must use same voltage, and power EPDC | 1.8V | VGEN4 |
| NVCC_EIM1 | | | |
| NVCC_EIM2 | | | |
| NVCC_NANDF | used for SD4 | | |
| NVCC_SD1 | primary boot | | |
| NVCC_SD2 | not used | | |
| NVCC_SD3 | expansion SD card | | |
| NVCC_JTAG | | | |
| VDD_SNVS_IN | battery backup supplyr | | |
| NVCC_CSI | UART | 3.3V for esp32 / debug | SW4 maybe (but slightly low) |
The page says I'd need three supplies:
- VDDARM_IN and VDDSOC_IN
- VDD_HIGH_IN
- everything else?