OCTVO-3P-OSD62X: Issue with VDD_SD dropping to 1.8V when SD card inserted (OSD62x-PM with AM625)

Mohit Sharma

Part Number: OCTVO-3P-OSD62X
Other Parts Discussed in Thread: AM625, SK-AM62B-P1

Tool/software:

Hello Shreenivasa,

I am currently debugging a latest SIP OSD62x-PM which uses the AM625 processor. I am facing an issue with the SD card power rail (VDD_SD).

When the SD card is not connected, I measure VDD_SD at 3.3V. However, when I insert an SD card into the slot, the voltage drops to 1.8V.

During testing, I verified that the VLDO1 output from the PMIC is stable at 3.3V, but the output of U11 (TPS22918DBVR), which is providing VDD_SD, drops to 1.8V after the SD card is inserted.

Could you please help me understand the possible cause of this behavior?
For the reference I had shared the schematic over chat.

Regards,
Mohit

3 months ago

0 Kallikuppa Sreenivasa 3 months ago

TI__Guru**** 199949 points

Hello Mohit,

Thank you for the query.

Please make the below changes

Please check the cap value used

use 2.2uF near PMIC and 1 uF near to SOC VDDSHV5.

Please add pullup for SD_PWR_EN and pulldown for RESETSTATz and do a check.

C74 should be populated with 220pF.

The SD card power switch connections seems to be having errors

QOD seems to be shorted to ground.

Please rewire as below

Regards,

Sreenivasa

0 Kallikuppa Sreenivasa 3 months ago in reply to Kallikuppa Sreenivasa

TI__Guru**** 199949 points

Hello Mohit,

Please use 1uF near to the output of the load switch and connect a 2.2uF cap near to the SD card socket VDD supply pin.

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Sreenivasa,

For now I have removed the U11 and shorted the pin 1 and 6. Now I am getting the VDD_SD as 3.3V but stuck while booting. No messages are shown in debug port.

Regards
Mohit

0 Mohit Sharma 3 months ago in reply to Mohit Sharma

Prodigy 110 points

just tested one board getting the below debug messages.

U-Boot SPL 2024.04-dirty (Aug 01 2025 - 15:38:38 -0500)
SYSFW ABI: 4.0 (firmware rev 0x000a '10.1.8--v10.01.08 (Fiery Fox)')
SPL initial stack usage: 13392 bytes
Trying to boot from MMC2
Authentication passed
Authentication passed
Authentication passed
Authentication passed
Authentication passed
Starting ATF on ARM64 core...

NOTICE: BL31: v2.11.0(release):v2.11.0-906-g58b25570c9-dirty
NOTICE: BL31: Built : 04:20:32, Nov 1 2024

U-Boot SPL 2024.04-dirty (Aug 01 2025 - 15:48:56 -0500)
SYSFW ABI: 4.0 (firmware rev 0x000a '10.1.8--v10.01.08 (Fiery Fox)')
SPL initial stack usage: 1888 bytes
Card did not respond to voltage select! : -110
** Bad device specification mmc 1 **
Couldn't find partition mmc 1:1
Error: could not access storage.
Trying to boot from MMC2
Card did not respond to voltage select! : -110
spl: mmc init failed with error: -95
SPL: failed to boot from all boot devices
### ERROR ### Please RESET the board ###

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Thank you.

Mohit Sharma said:
For now I have removed the U11 and shorted the pin 1 and 6. Now I am getting the VDD_SD as 3.3V but stuck while booting. No messages are shown in debug port.

With the shorting, you will not be able to reset the SD card - that means you will have to configure the SD care to use only legacy speed and fix the voltage to 3.3V.

This is a DBVR package - i would recommend that you either rework the board or change the software to fix the speed to legacy.

Regards,

Sreenivasa

0 Kallikuppa Sreenivasa 3 months ago in reply to Kallikuppa Sreenivasa

TI__Guru**** 199949 points

Hello Mohit,

Mohit Sharma said:
SPL: failed to boot from all boot devices
### ERROR ### Please RESET the board ###

I suspect the SD card needs to be reset to continue the boot.

Please fix the hardware or software.

Regards,

Sreenivasa

0 Kallikuppa Sreenivasa 3 months ago in reply to Kallikuppa Sreenivasa

TI__Guru**** 199949 points

Hello Mohit,

Can you please confirm if the schematics was a custom schematic or provided by 3P.

Kallikuppa Sreenivasa said:
QOD seems to be shorted to ground.

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Sreenivasa,

This is the custom schematic that has been made.

To change the software speed to fix the speed to lagacy is a bit hard task for me, I guess I had to make changes in device tree.
Please let me know if you have any inputs from software side to fix the legacy speed.

For now I will try to place U11 with pin 5 shorted to VOUT instead of GND.

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Thank you and understand.

Please make the hardware changes and let me know how it goes.

You may have to start another E2E thread for the software team to support configuring the SD card to legacy speed.

Refer below FAQ

(+) [FAQ] AM625 / AM623 / AM620-Q1 / AM62L / AM64x/ AM243x (ALV) / AM62Ax / AM62D-Q1 / AM62Px Design Recommendations / Commonly Observed Errors during Custom board hardware design –SD card Interface - Processors forum - Processors - TI E2E support forums

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Sreenivasa,

I have done the hardware changes by directly tying the pin5 of U11 to VOUT, But it shows me the same log as shown above.
For this I had also removed the R22 and pulled up the SDCD to VIN_3P3_LS but got the same result.

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Can you confirm the VDD supply to the SD card is being reset during boot.

You need to check with a oscilloscpe.

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Sreenivasa,

Did you mean the VDD_SD supply reset again after boot to detect the sd card again and then complete the booting process?

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Correct,

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Sreenivasa,

I had tested the board its not showing me the supply getting reset after boot.
Please let me know what can i do to make it work.

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Please start a new E2E thread with title SD card boot support and include the logs for software expert to support.

Regarding the hardware please compare the implementation with SK-AM62B-P1 schematics.

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1332316/faq-am625-am623-custom-board-hardware-design---design-and-review-notes-for-reuse-of-sk-am62b-p1-schematics

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Shreenivasa,

Please let me know does SD_PWR_EN or Resetstatz which one helps to reset the U11 IC.

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Thank you.

SD_PWR_EN should toggle to perform local reset.

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Sreenivasa,

I just opened the reference schematic shared by octavo systems of the board. There is no signal stated as SD_PWR_EN on the load switch to turn it OFF and then ON.

For the reference I am attaching the photo of the load switch.
There is Signal SPI0_D1 is which should be SD_PWR_EN but its is directly connected to the external header.

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Thank you.

I see the RESETSTATz pulled up that we do not recommend.

Have you tested the Octavo board for SD card interface and does that support UHS-I speed?

I need the full schematics to be able to comment.

I have not had a chance to view this specific schematic to comment.

I see the load switch implementation to be OK in the reference schematics.

Regards,

Sreenivasa

0 Kallikuppa Sreenivasa 3 months ago in reply to Kallikuppa Sreenivasa

TI__Guru**** 199949 points

Hello Mohit,

Checking if you made some progress.

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Sreevivasa,

I am trying to make changes on software side i.e., SD card legacy speed to 3.3V.

Regards
Mohit

0 Mohit Sharma 3 months ago in reply to Mohit Sharma

Prodigy 110 points

Hello Sreenivasa,

The issue is resolved with changing the legacy speed to 3.3V. Thanks for your help.

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Good to hear.

I suspect the same issue could be there in the module you are referring.

I can get the changes reviewed from the software expert if you can provide details on the changes made.

Regards,

Sreenivasa

0 Mohit Sharma 3 months ago in reply to Kallikuppa Sreenivasa

Prodigy 110 points

Hello Sreenivasa,

The issue was the SD card legacy speed to 3.3V

This can be done by adding "sdhci-caps-mask = <0x00000007 0x00000000>;" to the sdhci1 node in the k3-am625-osd625-brk.dts file.

Regards
Mohit

0 Kallikuppa Sreenivasa 3 months ago in reply to Mohit Sharma

TI__Guru**** 199949 points

Hello Mohit,

Thank you.

In case you do not have any additional queries, i will close the thread.

Regards,

Sreenivasa