S32KのトピックRe: S32K344 Standby Mode

S32K344 Standby Mode

vinaykl — Tue, 03 Feb 2026 05:17:07 GMT

Hi Team,

I checked the low power mode project shared by NXP team (S32K344_RTI_Cycl_Wkup_S32DS_3_4_RTD_LLD_2_0) in S32K344 EVB, but when it enters Standby mode, the current is still showing 60mA. That is not an idle consumption of the MCU as per the datasheet.

Kindly let me know how we can achieve lowest current consumption in the evk in standby mode.

Re: S32K344 Standby Mode

Julián_AragónM — Tue, 03 Feb 2026 22:05:53 GMT

Hi @vinaykl,

How are you measuring the current consumption? Have you disconnected J427 and measured VDD_HV_A_MCU?

Julin_AragnM_2-1770156112033.png

I have tested the S32K344_RTI_Cycl_Wkup_S32DS_3_4_RTD_LLD_2_0 example, and I can see 2.3mA in RUN mode, and 240uA in STANDBY mode.

If you are only measuring the power supply, this measures the current consumption of whole EVB, not just consumption of the MCU. It's not so significant in run modes but it's definitely not usable for low power modes.

Also, keep in mind you need to drive/pull input pins to either VSS or VDD to avoid leakage current. It was discussed in this community post: Solved: Re: S32K324 Tristate Pins before sleep - NXP Community.

Cyclic wake-up current is explained in chapter 6.9 from the S32K3XX data sheet. Current consumption is calculated on the average during the period switching between RUN & STANDBY.

Best regards,
Julián

Re: S32K344 Standby Mode

vinaykl — Mon, 09 Feb 2026 10:35:01 GMT

Hi Julian,

Thank you for your response.

We are able to get MCU into Standby mode and we could able to wake up the MCU from interrupt.
Here we need help. Actually PMIC in consuming 20 mA power. How we can make PMIC in Sleep or low power mode. And once we make PMIC in Sleep mode is it possible to wake it up after that?

Thank you,

Vinay

Re: S32K344 Standby Mode

Julián_AragónM — Mon, 09 Feb 2026 21:10:52 GMT

Hi @vinaykl,

Yes. Please refer to the following community posts:

Basically, you must send the FS26 two commands: 0xAA and 0x55 within less than 10ms and previously have selected a wake-up source.

Best regards,
Julián

Re: S32K344 Standby Mode

vinaykl — Thu, 12 Feb 2026 05:11:34 GMT

Hi Julian,
I had tried to make SBC in standby mode by sending 0xAA and 0x55 commands for 0x58 register in SPI. But Still the current consumption is same as before.

Kindly let me know where I am making mistake.

Adding Screenshot of SPI communication with SBC.

Thank youScreenshot 2026-02-12 103012.jpg

Re: S32K344 Standby Mode

Julián_AragónM — Thu, 12 Feb 2026 21:13:49 GMT

Hi @vinaykl,

I mainly support S32K devices. Since SBCs/PMICs are not my area of expertise, please help me by opening a new thread regarding FS26 SPI communication.

You can try using the s32k3_wb_fs26 example from the Solved: S32K344-WB (WhiteBoard) EVB source code examples. It uses the Sbc_User_Enter_Standby() function when entering Standby with the S32K344. It may prove useful to you.

Best regards,
Julián