MSPM0L2228: LFCLK/ VBAT issue

Staneslouse Sadeesh

Part Number: MSPM0L2228

Tool/software:

Hi Team,

I'm currently working with a prototype using MSPM0L2228 and need to drive the segmented display. However, in SYSCFG, it indicates that VBAT needs to be powered for LFCLK operation. Should I connect VBAT to VCC directly to address this issue? please see the attached image.

Additionally, I am unable to observe any COMS signals from the micro. Any insights or suggestions would be greatly appreciated.

Thank You

Regards

Staneslouse

over 1 year ago

+1 Janz Bai over 1 year ago

TI__Genius 10470 points

Hello Staneslouse,

Yes you are right. on MSPM0L2228, the LFCLK is powered by VBAT so the VBAT must be powered, you can connect VBAT to VCC if you don't need the LFSS when the MCU is powered off (The LFSS part you can refer to the chapter 8 of TRM). And you can find this description in the TRM: If the VBAT domain is not powered, the device doesn't have a valid LFCLK for these purposes.

Best Regards,

Janz Bai

0 Staneslouse Sadeesh over 1 year ago in reply to Janz Bai

Prodigy 220 points

Hi Janz,

Thank you for the confirmation. it is working now.

Kind regards,

Staneslouse.

0 Janz Bai over 1 year ago in reply to Staneslouse Sadeesh

TI__Genius 10470 points

You are welcome.

0 Zane Wei over 1 year ago in reply to Janz Bai

TI__Intellectual 1665 points

Hi Janz,

My customer test when connect VBAT to VCC, it will increase the power consume(increase 100-200uA current). My customer want to achieve low power mode. So can we let VBAT don't connect VCC? If don't use VBAT, can the chip work well?

Best Regards,

Zane

0 Zane Wei over 1 year ago in reply to Zane Wei

TI__Intellectual 1665 points

If don't use VBAT, can connect VBAT to GND to achieve low power. Refer this link:

https://e2e.ti.com/support/microcontrollers/arm-based-microcontrollers-group/arm-based-microcontrollers---internal/f/arm-based-microcontrollers---internal-forum/1393359/mspm0l2228-is-it-ok-to-tie-vbat-to-vss-if-it-is-not-required?tisearch=e2e-sitesearch&keymatch=VBAT#

0 Janz Bai over 1 year ago in reply to Zane Wei

TI__Genius 10470 points

Hello Zane,

As I mentioned in previous response, in fact, you can connect VBAT to GND if you don't need the LFCLK because it must be powered by VBAT.

Best Regards,

Janz Bai

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MSPM0L2228: LFCLK/ VBAT issue