MSP430F6766: Find a Microcontroller or Processor that can run for 28 days on 3 D cell Alkaline batteries

How often do you need to make an A/D measurement?

But I bet any MSP430 will meet your requirements.

Pretty much any MSP430 can run that long. The real question is how much power will be used by the SD card.

Logging data to SD cards can be tricky. You have to be able to buffer at least 750ms of data if you use a FAT file system. That  being the maximum FAT write time in the SD specification.

Hi Gerald,

I agree with Keith and David. 3 D cells should be plenty to get a month of runtime. It will depend on:

1. How fast they are sampling the ADC
2. How often (and how much) they are writing to the SD card

Why did you select the F6766 as a starting point? Almost every MSP430 will have an ADC and a SPI interface to achieve your requirements. You probably can find a lower cost option for your system.

The MSP430 glass break application note has some interesting remarks in section 2.9 on power consumption and low power modes. This is a different application of course, but this guide claim to get 416 days using 2 AAA at 80uA average current.

The MSP430 SD card guide will also be useful for you.

Regards,

Evan