Reduce power consumption in Thread applications

RE: Reduce power consumption in Thread applications

Marco Russi — Thu, 04 May 2023 13:06:16 GMT

Perfect. Thank you very much.

RE: Reduce power consumption in Thread applications

Edvin — Thu, 04 May 2023 13:04:38 GMT

[quote user="Marco Russi"]

Setting the option to compile my project as SED would turn my device into the deepest sleep compatible mode with thread? Right?

[/quote]

Yes. There is in particular one other thing you would want to do as well, and that is to turn off the UART logging (CONFIG_SERIAL=n), but you may want to turn it back on while developing. But to do current measurements, you probably want to turn it off temporary. Also disable all LED functionality, as this also will draw a significant amount of current in an end product (unless you intend to actually have it/use it).

BR,
Edvin

RE: Reduce power consumption in Thread applications

Marco Russi — Thu, 04 May 2023 12:55:59 GMT

Thank you very much Edvin! That is very useful.

Setting the option to compile my project as SED would turn my device into the deepest sleep compatible mode with thread? Right?

Should I also do something else to reduce the quiescent current?

Thank you.

Marco

RE: Reduce power consumption in Thread applications

Edvin — Thu, 04 May 2023 12:43:23 GMT

I see. The rate at which you check for updates can be as often or as rare as you like. But increasing the frequency would obviously impact your current consumption.

I suggest that you check out this:

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/protocols/thread/configuring.html#device-type-options

What you are looking for is a sleepy end device (SED).

If a node is a SED, you can still send messages to it, as if it was awake at all times. It will be the parent node's job to hold messages for the SED (child node). While there are no hard limits on how many child nodes one parent can have, but you will see that you will struggle with memory if you have way too many child nodes on one parent. So if you only need the low power nodes, be prepared that you will need some normal nodes in your network as well.

BR,
Edvin

RE: Reduce power consumption in Thread applications

Marco Russi — Wed, 03 May 2023 13:30:17 GMT

Hi Edvin, thank you for your answer.

My device is a battery powered sensor and it mainly sleeps and periodically (every few seconds or minutes, depending on the user configuration) it wakes up to send a data message to cloud. It also periodically send a message to cloud to check if there are any new configuration settings to download. This last part would ideally need to be with the lowest possible latency but since I use CoAp I have to send a request first and get any pending notification back in the response. A MQTT like approach would be better in future.

In conclusion I think that my device is more a sleepy device than e full node. The application is a network of these battery powered sensors connected to the same Thread network formed by a Raspberry Pi border router to provide Internet access.

Cheers.

Thanks.

RE: Reduce power consumption in Thread applications

Edvin — Wed, 03 May 2023 12:02:50 GMT

Hello,

What sort of Thread device are you thinking of? There are two "main" categories. Either it is a full node that has a relative short response time, but you also have sleepy end devices that are directly connected to a parent node, but they can spend more time sleeping, and only occasionally wake up and receive updates. They can however wake up whenever they like, if they have important messages. You would typically see light bulbs working as "full nodes", since they are mains powered, and you want them to react quickly, while a light switch can be a sleepy device that occasionally wakes up for updates, in addition to waking up to e.g. turn on the light on a button press.

So what are your latency requirements?

Best regards,

Edvin