AM5728: Programming PMIC for AM5728 processor

Cleatus Wesley

Part Number: AM5728
Other Parts Discussed in Thread: TMDSEVM572X

Hey!

I am new to processor designs. I was studying AM5728 EVM schematics from TI (https://www.ti.com/tool/TMDSEVM572X) and came across the use of POWER MANAGEMENT IC to power ON the processor. However, I am unable to figure out how this PMIC is being programmed. There are no provisions on the board to program this PMIC. The I2C from the PMIC is connected to the processor. How does the PMIC know what voltages to output without programming during initial boot up?

Regards,

Cleatus

7 months ago

0 Stanley Liu 7 months ago

TI__Guru 50045 points

Hi,

PMIC used on EVM has the default voltage programmed to support the safe voltage for boot the SoC. You can refer to AM5728 datasheet to find the safe voltage spec.

Once SoC is powered up and booted, bootloader can reprogram the PMIC voltage value via I2C.

0 Cleatus Wesley 7 months ago in reply to Stanley Liu

Prodigy 220 points

I have followed the same design as the TMDSEVM572X on my prototype board. However, when I power on the board, only the LDO RTC section on the PMIC is at 1.8V. All the other sections are at 0V. What am I missing here?

0 Josue Zamitiz-Ayala 6 months ago in reply to Cleatus Wesley

TI__Genius 15484 points

Hello Cleatus,

Please see the following documentation:

You could also look at other E2E queries for more information like this E2E thread.

Hope this is helpful!

-Josue

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AM5728: Programming PMIC for AM5728 processor