WiFi: achievable netto datarate


the new Verdin modules have a WiFi ac module with two antennas that is connected via a 4-bit SDIO to the SOC.

For the WiFi connection I would expect a netto datarate of up to 300 MBit/s (2 Streams with 80 MHz bandwith).

What is the datarate of the SDIO interface? Is it fast enough or will it be the bottleneck for the WiFi connection?

Best regards

Greetings @Mowlwurf!

According to both the i.MX 8M Mini and the AzureWave AW-CM276NF datasheets, the SDIO interface supports the SDIO v3.0 specification.
The highest achievable frequency for this interface is on UHS-I mode, with up to 208MHz in SDR mode and up to 50MHz in DDR mode.

According to NXP, this would correspond to a data rate of up to 400 Mbits/s in SDR mode and up to 832 Mbits/s in DDR mode.

According to the i.MX 8M Mini datasheet, the SoC supports the SDR104 mode (section and per the AW-CM276NF datasheet (section 3-1-4), the module also supports SDR104.

SDR104 corresponds to that 208MHz frequency which then yields 104MB/s or 832 Mbits/s.

Considering these numbers, the SDIO interface shall not be a bottleneck for the Wi-Fi connection.

Note that this information is specific to the Verdin iMX8M Mini. As my colleague @alex.tx mentioned, this might be different for other modules such as the Colibri iMX8X, which supports up to 50MHz speeds on the SDIO interface.

Many thanks for this detailed answer

You are welcome.

Best regards,