AM62X-PET-CALC: AM62X

Hello lin yang

Thank you for the query.

I need more details. 

Would you be able to share the schematics to do a quick check?

Regards,

Sreenivasa

Dear Kallikuppa 

               Thanks for your suppot,attach the schematic FYI~.

rx9000_main_240116.pdf

Please ignore the power tree page.

Hello lin yang

Thank you

VDrop - why is this pulled to 5V.

With partial schematics it takes some time to review.

Is customer not using the MMC interface or the content is deleted.

Can you please check the RESETSTATz and PORZ_OUT signals.

Regards,

Sreenivasa

Dear Kallikuppa 

         Thnaks for your remind.

VDrop - why is this pulled to 5V.

-->It doesn‘t mater,I just remove the R1016 to disconnect the net.

Can you please check the RESETSTATz and PORZ_OUT signals?

-->I find they can‘t output high,Does they need external pull-up?(By the way,D15\D16\D17\D64\D65\D66 DNP on the board)

Hello lin yang

Thank you

lin yang said:

VDrop - why is this pulled to 5V.

-->It doesn‘t mater,I just remove the R1016 to disconnect the net.

If connected, can cause leakage and affect start-up.

If PORZ_OUT or RESETSTATz is not high, this is an indication that the device is in reset.

This can help on the section of the schematics to focus.

Regards,

Sreenivasa

Dear Kallikuppa

           After I add an external pull-up to them,the waveform of RESETSTATz is shown in the following.It remains high(1.8V) for 4.2ms.

As you know the device is in reset.

Hello lin yang

Thank you

Can you please remove the pullup - we do not expect you to add pullup and them measure the PORz_OUT, MCU_PORz, RESETSTATz and the clock.

Can you please verify if this toggling is repeating.

Regards,

Sreenivasa

Dear Kallikuppa

          As you guessed, this toggling of RESETSTATz is repeating.

And a good news is that the debug uart output some information.

Hello lin yang

Thank you.

This is something related to PMIC. could be some residual voltage.

Can you capture all the supply rails from power-up.

the feedback for the PMIC should be taken after the output bulk cap, 

What PMIC part number are you using?

please verify the schematics is any of the attached device has 1.8V supply ( IO) and the input seen is 3.3V.

I have partial schematics and is difficult to review.

Regards,

Sreenivasa

Dear Kallikuppa

1、Can you capture all the supply rails from power-up.

What PMIC part number are you using?

-->We are using the TPS65219， and all the follow PMIC output voltage is correct and stable.（BUCK1 0.75V； BUCK2 1.8V；BUCK3 1.2V；LDO2 0.85V；LDO3 1.8V ；LDO3 2.5V）

2、But I find the SOC AMS6232 sends a reset signal every 150ms,

At the same time, the nRSTOUT of PMIC is abnormal.(Normal  1.8V)

3、Should I disconnect PORz_OUT（Pin E21）& RESETSTATz（Pin F22） of AMS6232 .

PORz_OUT

RESETSTATz

 nRSTOUT -->SOC

Hello lin yang

Thank you.

Please share the complete PMIC ordering part number.

Please probe MCU_PORz and PORz_OUT/RESETSTATz with respect to any of the PMCI DC/DC output.

Please disconnect MCU_PORz and verify the behaviour.

Regards,

Sreenivasa

Dear Kallikuppa

1、Please share the complete PMIC ordering part number.-->TPS6521903RHBR

2、Please probe MCU_PORz and PORz_OUT/RESETSTATz with respect to any of the PMCI DC/DC output.

MCU_PORz ->Yellow

PORz_OUT ->Red

RESETSTATz ->Blue

BUCK2_1V8 ->Green

3、Please disconnect MCU_PORz and verify the behaviour.-->Even though I disconnect the MCU_PORz, the system still keeps resetting.

Is it possible that the AM6232 chip has poor soldering？

Hello lin yang

Thank you.

There are multiple sources for MCU_PORz. Did you isolate all the inputs.

I MCU_PORz is a LVCMOS input, and the rise time should be less the 1000 ns 

Why is the MCU PORz such a slow pulse?

With partial schematics, i can provide limited inputs.

I also see that the MCU_I2C0 and WKUP_I2C0 left open.

We are recommending a pullup irrespective of the IO configuration. Refer pin connectivity table of the SoC.

Regards,

Sreenivasa

Dear Kallikuppa 

           There are multiple sources for MCU_PORz. Did you isolate all the inputs.-->    Yes ，I have removed D49、D50、R361.

            Why is the MCU PORz such a slow pulse?-->  I don't know ，the voltage is also abnormal. Even I modified the R15 to 1KΩ,but it didn't work.

            With partial schematics, i can provide limited inputs.-->  In fact, this is the complete schematic of the single PCBA under tested.

            I also see that the MCU_I2C0 and WKUP_I2C0 left open.--> Can you provide accurate detailed net name？

            Refer pin connectivity table of the SoC.--> Please share the "pin connectivity table of the SoC".

Hello lin yang

Thank you.

There is another connection from the PMIC  - please review

I2C signal information

Regards,

Schematics 

Dear Kallikuppa 

          To simplify the analysis, I  currently only keep the connection to SOC.

Please review I2C signal information-> As you can see(X) ,they are no connected.

All outputs of PMIC have always been correct and stable, except for MCU-PORz which is abnormal.So，Is it possible that this issue is related to SOC？

Hello lin yang

The connection you have shown is the output of PMIC to the SoC.

MCU_PORz is the input.

Can you please capture the MCU_PORz and the PORz_OUT waveform with all other components removed.

Please also probe the VDD_3V3 that you seem to be generating using a DC/DC.

Have you verified the 03 configuration and the recommended input voltage?

https://www.ti.com/lit/ug/slvucj2/slvucj2.pdf

Is the clock stable?

Regards,

Sreenivasa

Dear Kallikuppa 

             We have confirmed that the root cause of the boot issue is a welding issue.Thanks for your tireless support.

Hello lin yang

Thank you for the note.

welding issue - did you mean soldering issue and was this on the SoC ?

Regards,

Sreenivasa

Dear Kallikuppa

welding issue - did you mean soldering issue and was this on the SoC ?--》Yes， You are right.

Hello lin yang

Thank you for the inputs and appreciated.

Was the issue observed on a specific board or you had multiple boards that has soldering issues.

Regards,

Sreenivasa