Kinetis Microcontrollers中的主题 Re: LPTMR Current

LPTMR Current

astdom01 — Mon, 01 Jun 2015 07:28:08 GMT

Dear all

I am looking for the power consumption of the LPTMR peripheral in clocked by ERCLK in a low power mode for the KL25x series. I expected the information in the datasheet in table 10 Low power mode peripheral adders - typical value. But there is only I_TMP mentioned not I_LPTMR. I hope I_LPTMR is much lower then I_TMP!? Is this informatin available somewhere?

Thanx you for any hint.

Best regards, Dominic

Re: LPTMR Current

ericfoote1 — Thu, 04 Jun 2015 18:16:47 GMT

Hello Dominic!

Just to be clear, are you referring to 32 KHz ERCLK32K?

-Eric

Re: LPTMR Current

astdom01 — Fri, 05 Jun 2015 11:11:01 GMT

Hm, not directely - I would like to know the same information about current usage over temperature range as it is available in Table 10 of the Datadheet "Kinetis KL25 Sub-Family" about the RTC (I_RTC) but for the LPTMR peripheral.

The discription for the RTC is the following:

"RTC peripheral adder measured by placing the device in VLLS1 mode with external 32 kHz crystal enabled by means of the RTC_CR[OSCE] bit and the RTC ALARM set for 1 minute. Includes ERCLK32K (32 kHz external crystal) power consumption."

with the values: -40C -> 432nA, 25C -> 357na, 50C -> 388na, 70C -> 475na, 85C -> 532na, 105C -> 810na

For the LPTMR the discription could be:

LPTMR peripheral adder measured by placing the device in VLLS1 mode with external 32 kHz crystal enabled by means of the RTC_CR[OSCE] bit. Includes ERCLK32K (32 kHz external crystal) power consumption."

with the values: -40C -> XnA, 25C -> Xna, 50C -> Xna, 70C -> Xna, 85C -> Xna, 105C -> Xna

This information is available for TMP, UART, RTC, CMP ... but not for LPTMR event if the LPTMR can bu used in all Very-Low-Power modes.

I hope you understand my issue :-) Thank you and best regards, Dominic

Re: LPTMR Current

ericfoote1 — Tue, 09 Jun 2015 22:03:51 GMT

Dominic,

I came across this. It's from the data sheet for KL27, which also has a Cortex M0+ .

I also tested a few cases and arrived at room temperature and achieved similar results.

Hopefully this helps you some!

-Eric