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Can I go below 1uA during deep sleep?

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sgpee:
Fellow masters,

I like to design a board that works with a 1.5AAA battery. The processor and some of the other ICs require 3V so, I will have to use a DC-DC converter, that is no problem. The problem is, my device will be off 99% of the time and leakage is not fun.

So, I am looking for a solution that would get the power consumption of the system during off mode less than 1uA @ 1.5V.

I have an on-off button but that is not mechanical, so I cannot cut off the power mechanically, I need to do it electronically.

For example, I looked for a DC-DC converter with a button press/bounce logic to turn on the system (where I could turn off via uP). I also looked for a 1.5 ultra low power uP that I can use to control some switches so that I can cut off the power to even DC/DC. (no such uP exists, at least based on my research) Neither these approaches proved useful.

Now, I am at a loss and open to suggestions.

thx, sgpee

CryptLordGR:
why not use 2 1.5V batteries so that you dont need the DC-DC converter and use the the stand by mode of the uP. MSP430 is very efficient in battery when programmed correctly for less consumption. It is 0.4uA in Standby mode when powered by 2.2V in the worst case if powered by 3 it can't pass the 1uA

mikeselectricstuff:
Why do you think you need to get below 1uA?
Nominal capacity of an AAA is about 1000mAh, so 1uA corresponds to a life of about 100 years!
Unless you're using small coin cells, anything under 10uA is completely insignificant.

tinsmith:
SNUPI (PDF) is using the MSP430 to get an estimated 1.5 ?W during sleep (i.e. 1 ?A @ 1.5V). That level is achievable, and probably more than adequate if you just want to minimize leakage. But I don't think you're realistically going to beat it without custom logic.

EEVblog:
There are several boost converters that use less than 1uA in off mode.
The MCP1640, AS1329, and TPS61103 are several examples.
But I agree with Mike, why the concern?

Dave.

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