topic Re: FRDM-KL82Z - Power Manager Demo in Kinetis Microcontrollers

FRDM-KL82Z - Power Manager Demo

rtoma — Tue, 16 May 2017 14:13:59 GMT

Hi there,

I'm trying to get my head around the power modes of the Kinetis KL82Z microcontroller. At the moment I have a KL82Z Freedom board running the Power Manager Demo application from SDK2.2. I am not using the debug probe to run it. I am able to change the different power modes. The power modes I am most interested are VLPR and VLPS.

However, when switching from RUN to VLPR and afterwards to VLPS the values I am measuring are above the ones stated in the datasheet. I am placing the current meter in jumper J15.

	Current Draw (mA)
	Min	Max
RUN	10.1	10.14
WAIT	10.05	10.11
STOP	8.1	8.12
VLPR	1.481	1.602
VLPW	1.474	1.604
VLPS	1.402	1.523
LLS/LLS3	0.397	0.423
VLLS0
VLLS1
VLLS2
VLLS3
HSRUN	10.82	10.94

Is there something I am missing or doing incorrectly?

Is there some relevant material that one can read more? Relevant to the Kinetis L family microcontrollers?

If someone had a previous issue on a different Kinetis board, which is similar to mine, I would like to hear how they solved it.

Many thanks in advance!

Re: FRDM-KL82Z - Power Manager Demo

xiangjun_rong — Wed, 17 May 2017 09:47:20 GMT

Hi, Radu,

From hardware perspective, it is okay to connect a current meter to the J15 to measure the current of VDD pins. But from our experience, pls try to remove the KDS or the other tools to test the current, because the debug tools always wake up the processor. Pls have a try.

XiangJun Rong

Re: FRDM-KL82Z - Power Manager Demo

rtoma — Thu, 18 May 2017 07:15:23 GMT

Hello XiangJun,

Thanks for the reply. I am using the FRDM-KL82Z dev board. I will try and isolate the KL82 as much as possible.

I was hoping that NXP would make it easier measuring the low power current. I am investigating the dev board schematic in order to figure out how this could be done.

Re: FRDM-KL82Z - Power Manager Demo

rtoma — Fri, 19 May 2017 07:37:14 GMT

Thank you XiangJun! Powering the dev board via J11 solved the issue. I found this table in the FRDM-KL82Z User Guide.

The current measurements are starting to look more closer to the datasheet now.