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Low Power Cortex M?

Cpt. Vince

I am looking for the lwest power Cortex M-?

I don't want to spend years searching the internet for a low-power ARM Cortex controller.

Does anybody know of one?

(And yes, it is Keil related since I'll be using Keil to program it)

Thanks,

--Cpt. Vince Foster
2nd Cannon Place
Fort Marcy Park, VA

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  • 0 in reply to Cpt. Vince

    Note that both the Cortex-M3 and the ARM7 chips are available in different geometries, and there are large differences in power consumption.

    But the consumption of the processor core should not vary too much from different offerings using the same manufacturing process which was my claim from my first post.

    And I did mention explicitly "But in the end, the peripherials may be the big difference, since they can stand for a significant percentage of the total consumption and are what differs between the manufacturers."

    One manufacturer may have a tiny timer. One may have a timer with a ton of configuration bits.

    The (non Cortex-M3) LPC23xx chips have a broken implementation of the RTC + battery-backed RAM, making the processor gobble a lot of current and making NXP officially drop the support for one power-save mode instead of adding an errata. For me, that little design misfeature represents about 50% of the power consumption at the lowest power-save mode for a design with a LPC2366. In the end, the 32kHz slow-clock mode wasn't meaningful to use because of power leakss inside the chip when the internal 1.8V DC/DC was turned off. And the power leaks required an external RTC because we couldn't afford the required battery/supercap size for using the internal RTC.

    When reaching these low powers, it will be enough with quite small engineering errors to get the modules around the core to consume more than the core.

    The problem is that chips mentioned to be released somewhere in 2010 may have still unknown errors in them, affecting their true power consumption. When will a buyer know that a "super" chip is really as good as the initial projection.

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  • 0 in reply to Cpt. Vince

    Note that both the Cortex-M3 and the ARM7 chips are available in different geometries, and there are large differences in power consumption.

    But the consumption of the processor core should not vary too much from different offerings using the same manufacturing process which was my claim from my first post.

    And I did mention explicitly "But in the end, the peripherials may be the big difference, since they can stand for a significant percentage of the total consumption and are what differs between the manufacturers."

    One manufacturer may have a tiny timer. One may have a timer with a ton of configuration bits.

    The (non Cortex-M3) LPC23xx chips have a broken implementation of the RTC + battery-backed RAM, making the processor gobble a lot of current and making NXP officially drop the support for one power-save mode instead of adding an errata. For me, that little design misfeature represents about 50% of the power consumption at the lowest power-save mode for a design with a LPC2366. In the end, the 32kHz slow-clock mode wasn't meaningful to use because of power leakss inside the chip when the internal 1.8V DC/DC was turned off. And the power leaks required an external RTC because we couldn't afford the required battery/supercap size for using the internal RTC.

    When reaching these low powers, it will be enough with quite small engineering errors to get the modules around the core to consume more than the core.

    The problem is that chips mentioned to be released somewhere in 2010 may have still unknown errors in them, affecting their true power consumption. When will a buyer know that a "super" chip is really as good as the initial projection.

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