Lowest power ARM MCU?

I don't think you will be interested in the Intel parts. They are not MCUs and require external program storage. I believe the Atmel SAM7 parts have the lowest power level for a given MIPS. You can find more info in a comparison chart at

Go to the resources page and scroll down to the ARM Chips section. There you will find an ARM MCU comparison chart with details such as power consumption. It displays better in Firefox than IE. I believe the power numbers for the Atmel parts assume you provide a separate Vcore voltage of 1.8 volts. If you use the internal LDO the power levels will be higher.

I recall someone mentioning that there is an async part coming out that will consume power according to your processing requirements. It may be Philips, I don't recall. This would save you the trouble of matching the clock to your MIPS requirement.

LPC3180 is the current leader, 90nm process, .9 V core, about

0.5mW/Mhz at 13Mhz(so I guess you can run it at 2-4 Mhz but the power levels don't usually scale down linearly due to a fixed leakage current) 128kb RAM, hardware floating point unit, like all leading edge stuff, it is samples now, no production

oops,forget my post, it's ARM9, you were looking for ARM7

I'd tend to think the 2101/2/3 would be your best bet. It also depends on what on-chip peripherals are being used because this chip can power down some of them when they aren't used. Also, sometimes the power ratings are over the temperature range, and you can get better than that with typical numbers. I think you're looking at 7 ma for 10 Mhz at room temp. If you only need 1 Mhz it should be much lower than this.

AT91R40008 (256 kB internal SRAM) is 0,83 mW/MHz. Recalc: 8,3 mW/10 MHz @ i1.V => 4.6 mA @ 25'C.

The LPC2101 would therefore be 50% more power hungry.

--
Best Regards,
Ulf Samuelsson
ulf@a-t-m-e-l.com
This message is intended to be my own personal view and it
may or may not be shared by my employer Atmel Nordic AB

Does Atmel have a device with flash that should be considered for low power applications? Most modern Atmel Arm chips seem to target the high integration market, and I figured they'd use a lot of current.

Since I have your attention, this might be a good time to ask about upcoming products. Philips is very vocal about their lpc2888 and the lpc23xx and lpc24xx upcoming devices. But I rarely see insights into what Atmel is doing. Would it be possible for you to tell us what's coming? My current desire is to use USB OTG (on-the-go)... but I constantly look for low power devices also (non-usb, of course). I'd like to trade-up from the MSP430 on one of my apps ...

Have you considered another core? The ARM wasn't designed for low power operation, really. Ulf will tell you that Atmel is best, of course :-)

PIC24 is a good compromise, with a wide instruction word (24 bits) but

16 bit data paths. It is (I believe) 0.25 micron. Not that geometry is going to give you a reliable idea of consumption... It performs better at 40 MHz than an ARM7 at 60MHz... Also has an excellent interrupt structure and low cost tools... Its host port can be used for interfacing to external LCD etc.

-Andrew M

I just proved that Atmel can do better than the Philips 7 mA ;-)

BTW: the LPC2101 is not 90nm, it is 0,14 or 0,16

--
Best Regards,
Ulf Samuelsson
ulf@a-t-m-e-l.com
This message is intended to be my own personal view and it
may or may not be shared by my employer Atmel Nordic AB

You should have read my post above...

I believe the Atmel SAM7 MCU parts have the lowest power level for a given MIPS. You can find more info in a comparison chart at

Go to the resources page and scroll down to the ARM Chips section. There you will find an ARM MCU comparison chart with details such as power consumption. It displays better in Firefox than IE.

Not really. I thought the ARM7 would be the most mips for under 10mA. I'd still gravitate towards ARM7 for all the tools available. I'm aiming for ecos, graphic LCD, and for a slightly different project, linux, for which I'm also looking for low power stacked flash+ram.

I'll take anything 16-bit+ that can do ecos and linux, I think I'm asking for 32-bit.

Speaking of 16-bitters, I love the specs on the TI parts. Someone should do that for arm. I'd spend the money for small quantities for much more expensive ARM chips if theyre better than 90nm and perform like champions on under 10mW. They dont exist.

The AT91SAM9261 has a built in framebuffer. This is useful since you can power down external memory and still keep the display alive.

--
Best Regards,
Ulf Samuelsson
ulf@a-t-m-e-l.com
This message is intended to be my own personal view and it
may or may not be shared by my employer Atmel Nordic AB