ESP32 - Analog trigger for waking-up

Hi guys,

I've been working with ESP32 for the last months and I've been successfully able to implement projects where the condition for waking-up the device was digital. Like, if a button is pressed, wakes-up and do something.

A new challenge has arrived and now I need to read a weight sensor and based on a maximum threshold I should wake up the device and perform the tasks.

Yes, power consumption is an issue in this project and batteries will be used.

Is there a way to do this? Can I get a direction from you guys on how to achieve this? Is ESP32 a good option for this project?

Thank you!

If you want to detect a threshold value without a clock (lowest power), you need a microcontroller with analog comparators. They allow you to disable all digital logic and draw very little current.

Which device depends on what else you need. Most microcontroller vendors have special low power families.

Thank you Klaus for replying.

Apart from the analog input, the microcontroller would need to have a SIM card 4G capability built-in, because I need to send data to the internet in case the analog threshold has been exceeded.

Would you be able to point out a suitable microcontroller?

I would split the system. Get a separate microcontroller to do all the low power stuff. It can then power up the modem and send the data.
Things that are 4G capable are not low power, so you need this to be powered off 99.9% of the time.

For the microcontroller check out the websites from Microchip/Atmel, ST and NXP. Then use some parametric search ether on their side or a distributor. how many I/Os, do you need a RealTime clock, … and the analog comparators