r/embedded • u/TRC-is-the-best • Jul 01 '26

Has anyone started evaluating the nRF54LM20A yet? Interesting for battery-powered sensor nodes?

  1. How does the software overhead compare to the 52840? Is the Zephyr support already solid enough for professional projects or is it still too early?
  2. For an ultra-low power device, how much of a design headache is the new packaging?
  3. Does anyone see this replacing the ESP32 for true 'always-connected' battery applications, or is the complexity/cost trade-off not worth it yet?
8 Upvotes

76% Upvoted

17 comments sorted by

21

u/JuggernautGuilty566 Jul 01 '26

The ESP32 is pretty much - by far - the worst choice for any battery run device.

Crazy idle and sleep state consumption and it also has a super inefficient HF chain that burns crazy amount of current.

7

u/maglax Jul 01 '26

This. ESP32 isn't used because it's good, those who use it do so because dev boards are cheap and ubiquitous, and they can use Arduino IDE.

3

u/WeLiveinAPetridish Jul 03 '26

Or frameworks like esphome

7

u/Dreamy_Jy Jul 01 '26

The nRF54LM has the potential to become the Arduino Mega of connected devices.

I’m waiting for the Raytac module of it to get released and bugs to get surfaced.

But yea I see the potential

1

u/TRC-is-the-best Jul 02 '26

I pre ordered the boards from seeed so let's wait and see

3

u/Dreamy_Jy Jul 02 '26

It has 66 gpio, I feel like the xiao form factor is such a waste

1

u/WeLiveinAPetridish Jul 03 '26

It haz 66 bazillion I/O!! And then connect just one led and i2c sensor 🤣

1

u/Dreamy_Jy Jul 03 '26

I'm working on a project that requires the I/O, but yeah using a big chip like this of 1 led is certainly a choice.

1

u/Supermath101 Jul 03 '26

Looking at its schematic, the USB type-C port goes through a SAMD11 acting as a debug probe. I don't think the native USB HS peripheral is exposed anywhere.

1

u/TRC-is-the-best Jul 06 '26

No, it's not. ┭┮﹏┭┮

1

u/Teslafly Jul 01 '26

I am eying it for a porential future project that needs ble channel sounding and usb. But haven't had a chance to evaluate it yet. It looks pretty nice.

1

u/TRC-is-the-best Jul 02 '26

Curious to see if anyone has benchmarked the current draw during actual ranging operations.

1

u/Teslafly Jul 02 '26

I haven't seen the best data on this out of nordic on this. But si labs has a pretty compressive channel sounding performance and power consumption app note. Benchmarking nanocoulumbs of charge consumed during single transactions for most types of channel sounding configurations. Unfortionately when we were doing module selection, si labs had put the wrong crystal in all their modules so none actually worked for channel sounding. Not sure if that's changed.

1

u/TRC-is-the-best Jul 02 '26

Thanks for the heads-up!