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Comment by dz0ny | Hacker News Reader

Lol not true, you even have a low-power core (https://docs.espressif.com/projects/esp-idf/en/latest/esp32/...) in each esp which lasts on a coin battery for years.

Sure it won't last long if you use pause and you are connected to wifi. You have boards with a power management chip that allows you to do even more smarter things, for example https://www.hackster.io/news/smart-bee-designs-bee-s3-is-a-1...

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The ULP coprocessor only claims a power consumption of 150 uA (which is huge compared to actual low power devices - EFM32, which is an ARM Cortex M3 MCU, runs on just 1.45 uA)

Combine that with the fact users see real power consumption up at 450 uA [1], you won't be writing a program that lasts more than about 3 weeks on a regular CR2032 coin cell.

[1]: https://github.com/espressif/esp-idf/issues/7882

That's a 2 year old github bug being fixed, not the actual usage people obtain in the wild.

Here's [1] a commercial ESP32 board that draws 1.5uA, and, as others point out, comes with vastly more hardware at a lower cost [2] than the EFM32 arm core you listed.

[1] https://www.tindie.com/products/kdcircuits/trigboard-ultra-l...

[2] $1.10 for ESP32-C3 on digikey, vs $1.34 for EFM32PG22C200F64IM32-CR. The ESP-32 is better for pretty much every spec possible.

This was then resolved (id depends on the use case also), also you are comparing Low Power CPU (ARM Cortex m0-m3), which you need to pair with something probably esp32 to connect it to the internet.

Yeah, por ir on deep sleep and wake it up briefly once a day and try not to use wifi

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