What is picoPower?

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Atmel mentions picoPower, but I don't see it defined anywhere. Can anyone tell me what this is?

"AVR4013: picoPower Basics" [1] takes the ATmega88PA as example. The parametric table [2] says it has picoPower. Its datasheet [3] also covers ATmega48A/PA/88A/PA/168A/PA/328/P. The Atmega88A doesn't have picoPower according to the parametric table. Yet, the typical power down current curves [4] are practically identical.

The "Supply Current of IO Modules" [5] are listed identical.

Searching the datasheet for 'pico' gives this: "Note: 1. BOD disable only available in picoPower devices ATmega48PA/88PA/168PA/328P" So, is this it? PicoPower is the ability to turn off BOD during sleep?

picopower.aspx [6] says:

"True 1.62V operation

Central to the AVR picoPower technology are carefully designed analog functions that continue to operate all the way down to 1.62V.

Atmel AVR microcontrollers offer true 1.62 V operation, including all analog modules, oscillators, and flash and EEPROM programming."

In the datasheet I don't see these 1.62 V, but 1.8 V:

"Speed Grade:
"“ 0 - 4MHz@1.8 - 5.5V,
0 - 10MHz@2.7 - 5.5.V,
0 - 20MHz @ 4.5 - 5.5V

Common DC characteristics TA = -40°C to 85°C, VCC = 1.8V to 5.5V (unless otherwise noted)"

Why are they calling it picoPower anyways? The minimum current draw is about 100 nA at umm ... 1.62+ V - that's 162 nW.

Thanks, Bernhard

[1]
http://www2.atmel.com/System/Red...

[2]
http://www.atmel.com/dyn/product...

[3]
http://www.atmel.com/dyn/resourc...

[4]
Sections 30.3.4 and 30.4.4

[5]
Sections 30.3.3 and 30.4.3

[6]
http://www2.atmel.com/technologi...

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One of the attributes of the PicoPower architecture is the ability to turn off more of the peripheral modules.

Whether one of the PicoPower devices will save you power is determined by what I/O devices you need on, and for how long. The PicoPower device spec sheets generally give you graphs or tables of the current consumption of each interface under a variety of conditions. You need to go though the ones you want to use (under the sleep/wake scenario that applies to your application), add them all up, and compare that to the non-PicoPower version. You might or might not come out ahead with the "P" device.

Jim

Jim Wagner Oregon Research Electronics, Consulting Div. Tangent, OR, USA http://www.orelectronics.net

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Sleeping BOD.

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Yet, the typical power down current curves

On more modern AVRs you will not find a significant difference in power-down current (I think 0,1uA) but some older AVRs like m16 or m8 consume more then.
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PicoPower is the ability to turn off BOD during sleep?

Mind m169P does not.
The datasheets state you can keep the AVR in sleep down to POR voltage, so it is safe to disable BOD in this region. That BOD current is a major consumer when in power-down, so "this is it" is a really useful feature. Together with PRR.

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Why are they calling it picoPower anyways?

To make you believe in it. It is a marketing slogan and I bet most of their customers did believe.

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True 1.62V operation

I didn't notice that.. Looks like a mistake.

No RSTDISBL, no fun!

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Quote:

Quote:
True 1.62V operation

I didn't notice that.. Looks like a mistake.


Well, true enough that the Speed Grades curves shut off at 1.8V. As with other chips/brands, the Typical Characteristics section lists the 1.8-5.5V range--but that might not be the limits per se but rather the range in which the tests were done.

Of interest might be the POR numbers, which do indicate the 1.6 level.

I had a Mega48P app which ran reliably somewhat below 1.0V.

Also, consider extremes of temperature along with supply V. At the extremes, to guarantee operation, it is a "derating" of about 10%. Makes sense to me. I guess if they say the core is 1.6V I'd tend to believe it.

==================
Back when I was your age, it was difficult if not impossible to make a true low-power AVR design. Mega8/Mega16 era; won't even consider AT90nnnn. MSP430 and others would blow away the AVRs. Now, however, one can get an app down to below the shelf current of the battery. (And that's when I stop looking for uA.)

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Quote:
I had a Mega48P app which ran reliably somewhat below 1.0V.

I tried m16 (not A but regular old good m16) and run its RTC down to 1V. I didn't test the core, but RTC only. Works OK, stops below 1V. At about 0,8V a POR occurs.

No RSTDISBL, no fun!