All, Just following up from our discussions in the call on 20th June:
Typically an off-the-shelf commodity MCU standby power draw (with RTC enabled) would be less than 2uA at the battery terminals (including power draw of constantly running 32kHz crystal oscillator). So using a 150 mAh coin cell (with a rated 5 year self discharge time) with an MCU in a low power mode (RTC running) you would theoretically get greater than 8.5 years of battery life - ignoring self discharge. Using a "state-of-the-art" low power MCU you might get this up to 34 years (again ignoring self discharge). Basically standby power draw is not a limit here. The above assumes a commodity 32768 Hz watch crystal which gives 20ppm clock accuracy "at room temperature". Expect a volume cost for the crystal in the range $0.10-$0.25. If you need better timing/temperature stability then it could become significantly more expensive in both BoM cost and power consumption. Regards, Peter Aldworth IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. _______________________________________________ Ace mailing list [email protected] https://www.ietf.org/mailman/listinfo/ace
