[NEW HARDWARE REQUEST] Silicon Labs EFR32MG26 based Zigbee Coordinator USB adapter from ITead/Sonoff?

[Hedda]

@Daniel-zhan-itead @liangjia2019 @guozi7788 can you please forward a hardware request to ITead/Sonoff product managers?

Note! This is a new request to ask for EFR32MG26 based dongle, and related to previous request for a EFR32MG24 based dongle:

• [NEW HARDWARE REQUEST] Silicon Labs EFR32MG24 based Zigbee Coordinator USB adapter from ITead/Sonoff? #26

I would like to suggest that Tead/Sonoff as a company seriously consider looking into making and selling an new/upgraded variant of your existing ITead's Sonoff ZBDongle-E (Silicon Labs EFR32-based Zigbee Coordinator USB dongle radio adapter) that would instead be based on a new Silabs EFR32MG26 (EFR32 MG26 model) SoC chip with much more RAM + loads more Flash, (which is hopefully something that should more or less should make it future-proof):

https://www.silabs.com/wireless/zigbee/efr32mg26-series-2-socs

To copy naming scheme of Apple and others suggest that you call an EFR32MG26 based dongle for "Sonoff ZBDongle-E Pro Max" or something similar to indicate that it is the very best variant in that product-line, so if you do ever also make EFR32MG24 based variant too then you can just calll that "Sonoff ZBDongle-E Pro" to simply indicate a more higher-end variant than the previous model, however, do still continue to sell your existing "Sonoff ZBDongle-E" regardless for a lower price as a low-end budget option, (as well as "Sonoff ZBDongle-P" dongles as sure people will still want those too). 😉

Anyway, do make sure to keep the external antenna the same as of the previous design as before, but highly recommend that you reconsider redesigning a new dongle for a such EFR32MG26 or EFR32MG24 USB adapters so that it is a little smaller and with a longer USB plug so that there are no issues connecting it to all types of computers since your old Sonoff ZBDongle-E (and Sonoff ZBDongle-P) are infamously known for having a too short USB plug so will not work without a USB extension cable in many cases if the computer has its USB ports sunken too deeply. It is also too wide plugging it in directly normally means that the users can not use other USB ports that are too close as the wide enclosure of the ZBDongle design blocks other ports.

Please also keep in mind the board still needs to have good electromagnetic shielding -> https://en.wikipedia.org/wiki/Electromagnetic_shielding

Also recommend you consider always shipping at least a 1-meter USB 2.0 extension cable with good shielding with this USB dongle in the same package as it really makes a night and day difference in noise from EMF interference, (which is why the Home Assistant SkyConnect / Home Assistant ZBT-1 USB dongles ships with a 0.5 meter long USB extension cable, though it has been proven to work better with an even longer extension cable).

Note! Perhaps the main valid technical arguments for wanting a new Zigbee Coordinator USB dongle radio adapter that is based on this newer EFR32MG26 is that the older dongle was based on EFR32MG21 which has much less RAM and Flash/Storage resoucres so is therefore limited to connecting around 200 Zigbee devices at most, while the newer EFR32MG26 have more than 5-times the RAM so should in theory be able to connect around up to 1000 Zigbee devices. It is important that the new EFR32MG26 is have many other minor radio improvements which would make it an overall better Zigbee Coordinator then the EFR32MG24, and significantly better than the EFR32MG21.

https://www.silabs.com/wireless/zigbee

Additional information

Note that there are variants of EFR32MG26 that have less RAM and Flash Storage or less dBm in power amplification, so be sure not use use one of those. You want to instead be sure to use one that has larger RAM of data memory and larger flash program memory, Also note that there are as well a few special variants that in addition offer onboard AI/ML acceleration for extra cost so might be worth getting that if available to offer a premium product.

I believe some SoCs should be pin-compatible with their previous EFR32MG21 and EFR32MG24 chips so I think in theory that you should be able to simply update your Sonoff ZBDongle-E relatively easily if you did not also want to add additional improvements to the board design.

Silicon Labs (sometimes also referred to as "Silabs") has released its new EFR32MG26 radio MCU SoC which is a direct upgrade replacement for its EFR32MG24 and EFR32MG21 series with SoC variants with larger flash storage, much more RAM and a faster CPU so those EFR32MG26 SoCs with more resources (especially RAM) than the EFR32MG26 you use in the current Sonoff ZBDongle-E model should be capable of handling many more Zigbee devices, and it in additional also on paper it offers improved reception and less noise sensitivity.

FYI, that they have not yet released MGM260P (MGM260 radio module based on EFR32MG26 with + 20 dBm power ampified transmitter):

https://www.silabs.com/wireless/zigbee/efr32mg26-series-2-modules

PS: There are also a EFR32MG27 series but that is not meant for Zigbee Coordinator but instead only for Zigbee End Devices.

[Hedda]

@Daniel-zhan-itead @liangjia2019 @guozi7788 Oh! And please also consider implementing "hardware flow control" as standard on this EFR32MG26 model as that would make it stand out further compares to previous model that only had "software flow control"!

FYI, for reference relevant to this; there is currently a known bug when using software flow control with all the current versions of EmberZNet 7.4.x, 8.0.x, and 8.1.x that there is still no bug-fix available for. Nerivec has reported a bug as an issue to upstream where EmberZNet 7.4.0 still in all 8.0.x and 8.1.x you can see UART buffering issues and "appears to have changed in a way that makes the NCP very unstable under load (like an ongoing OTA on the network), it will throw a lot of max ACK timeout count errors. A "mostly-working" workaround appears to be increasing the default SL_IOSTREAM_USART_VCOM_RX_BUFFER_SIZE from 32 to 128 or above. This affects mostly software flow control (so, unclear on 8.1.0 because of first point), and appears pre-dominantly on CP210x-driven modules." ...so that bug does affect some of the existing EFR32MG21-based Sonoff ZBDongle-E when using Zigbee Coordinator that has a CP2102N/CP2102 (CP210x) USB to UART Bridge VCP. FYI, you can find that and other bugs reported to Silicon Labs here:

• https://github.com/SiliconLabs/simplicity_sdk/issues