topic Re: KW36 Power management in Kinetis Microcontrollers

KW36 Power management

sathyamoorthy — Fri, 22 Sep 2023 12:51:46 GMT

KW36 microcontroller enters the Low leakage stop mode.I have confirm whether it enters low leakage mode or not by measuring the current before LLSM and after LLSM. I am using LPTMR timer for wakeup the MCU and I have done the configuration in the LLWU wakeup unit as i am using LPTMR timer internal module .But after interrupt generating also MCU is not wakeup from the LLSM.Why please tell me

Re: KW36 Power management

EduardoZamora — Mon, 25 Sep 2023 21:19:05 GMT

Hello @sathyamoorthy,

Hope you are doing well.

Which version of the KW36 are you using? Please make sure you are using the latest SDK version available, you can download it from the MCUXpresso SDK Builder.

What is the method you are using to measure the current of your device?

Could you please provide more details about your application? Which demo application from the KW36 SDK are you using as base for your development? Is it a wireless example? BLE demo applications from the KW36 SDK should be optimized for low-power mode.

Please, take a look at the Kinetis MKW36 Power Consumption Analysis. This document provides information about the power consumption of KW36 wireless MCU, how the hardware is designed and optimized for low-power operations and how the software shall be configured in order to achieve the low-power profile measurements.

How are you modifying the base source code to handle low-power? What procedure are you following to enter and exit low-power mode?

Regards,
Eduardo.

Re: KW36 Power management

Srinivasan_V — Thu, 28 Sep 2023 10:26:16 GMT

To enter the low power modes i have used functions like these,

SMC_SetPowerModeProtection(&a ,kSMC_AllowPowerModeAll);
SMC_PreEnterStopModes();
SMC_SetPowerModeLls(&a,&config1);

To exit low power mode i have used functions like

LLWU_EnableInternalModuleInterruptWakup(bas,0,1);

LPTMR_GetDefaultConfig(&con);

LPTMR_Init(DEMO_LPTMR_BASE,&con);

LPTMR_SetTimerPeriod(DEMO_LPTMR_BASE,1000);

LPTMR_EnableInterrupts(DEMO_LPTMR_BASE,kLPTMR_TimerInterruptEnable);

EnableIRQ(DEMO_LPTMR_IRQn );

LPTMR_StopTimer(DEMO_LPTMR_BASE);

LPTMR_StartTimer(DEMO_LPTMR_BASE);

Here ,to exit the low power mode i have used a low power timer,and i have configured that in LLWU wakeup unit also.

I am using the SDK is FRDM-KW36(MKW36Z512XXX4),but actually my micro controller part number is like it was written on the IC M36A

W9V4 1N41U CTJQJD (with free scale semiconductor symbole).

Yeah that SDK is BLE demo application only.

Regards ,

Srinivasan V.

Re: KW36 Power management

Srinivasan_V — Thu, 28 Sep 2023 10:40:21 GMT

Please reply to Srinivasan_V

Re: KW36 Power management

Srinivasan_V — Thu, 28 Sep 2023 12:48:31 GMT

And I have tried to wake up MCU by connecting the reset pin to ground externally ,this method works .But i don't want this method ,i want to use that internal modules like LPTMR or RTC to wakeup the MCU.Now that LPTMR timer interrupt also generating but MCU was not wakeup, RTC interrupt also generating but MCU was not wakeup .These internal module wake up source was configured by LLWU.I have tried many times but it wont works ,help me.

Re: KW36 Power management

EduardoZamora — Thu, 28 Sep 2023 19:13:35 GMT

Hi,

BLE demo applications from the KW36 SDK should already implement low power. Please, take a look at the BLE Demo Applications User Guide, Chapter 5 of this document describes the demo applications that can be found in the software development kit. It presents the profiles and services implemented and how to interact with them. Also, some chapters mention the low power mode used in the corresponding demo application.

MKW36 Power Consumption Analysis, Chapter 4 Power managements and analysis, Section 4.2.2.1 Overview (Measurements and results) shows the current consumption of the KW36Z SoC during different operational phases using BLE Heart Rate Sensor application for the demonstration.

Also, these demo applications should allow you to use PWR (LPM) Library. This module offers access to interface functions and macros that allow the developer to put the device into the low-power or sleep modes. For more information on this, please refer to Connectivity Framework Reference Manual (KW36 SDK > docs > wireless > Common), Section 3.15 Low-power library.

Regards,
Eduardo.

Re: KW36 Power management

AndreVB — Tue, 03 Oct 2023 22:24:35 GMT

Hi Srinivasan,

Not sure it will help, but I have a code used with another MCU.

To enter Stop mode:

		LLWU_SetExternalWakeupPinMode(LLWU, 14, kLLWU_ExternalPinFallingEdge);
		EnableIRQ(LLWU_IRQn);

		smc_power_mode_vlls_config_t vlls_config;
		vlls_config.subMode = kSMC_StopSub1;

		SMC_PreEnterStopModes();
		SMC_SetPowerModeVlls(SMC, &vlls_config);
		SMC_PostExitStopModes();

To exit

 LLWU_ClearExternalWakeupPinFlag(LLWU, 14);

void LLWU_HANDLER(void)
{
     LLWU_ClearExternalWakeupPinFlag(LLWU, 14);
}

I instantiate LLWU_ClearExternalWakeupPinFlag(LLWU, 14); within the main(void) as well as within the LLWU_HANDLER(void). And of course, you have to config pin 14 as LLWU first.

Hope it helps.

Andre

Re: KW36 Power management

Srinivasan_V — Wed, 04 Oct 2023 04:29:32 GMT

Hi Andre VB!

Thanks for your help, Actually i have to implement the wakeup using the internal modules like LPTMR. if you have any idea means ,kindly help me.

Re: KW36 Power management

AndreVB — Wed, 04 Oct 2023 13:53:41 GMT

I remember I used the KL25 example Power Modes as reference for my project, and that was based on the LPTMR.

Good luck!