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suggestion for blog topic -- low power design

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I remember dave breifly talking about low power electronics design on the amp hour. It might be a good blog topic to expand upon this. What are some of the common techniques? How can I avoid pissing away current in using a 10k pull-up resistor?

I'm sure many of us will find such an episode interesting :)

it is probably a very broad subject that starts with choosing low power parts and knowing the details specs of your parts and how far you can push them

It depends on the input impedance and the logic levels.

Here's a PIC tutorial I'm following which discusses the issue of pull-up resistors, read the first couple of pages.

you using assembly ?


--- Quote ---it is probably a very broad subject that starts with choosing low power parts
--- End quote ---
That's not always the case - the knack is understanding how to get the result you need with the lowest power, and in some cases, the lowest power part is not the best choice.
In many cases the critical parameter turns out to be the length of time tnings are turned on, not the current draw whilst on.
A good example is sensing analogue values, e.g. temperature or pressure, on a low duty cycle.
In this sort of application you need to  turn on the sensor and often an amplifier, wait for it to settle, read the value and then turn off.
In practice, the settling & measurement time is often the  most critical value, as everything is powered, and often the CPU running as well. 
Where there is an amplifier, a fast opamp is generally more desirable than an ultra low power one, as the latter will be trading speed for power draw.

For a microcontroller, things like the number of different selectable clock rates and watchdog rates, provision of different levels of sleep, available wakeup methods and oscillator start-up time can make a bigger difference to overall power draw than the actual current draw in each mode.


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