i.MX 8M Plus PEVK Power Consumption by M.2

[iamRoy]

Hi,

I would like to see power consumption by the WLAN card while the WiFi is in different states (Sleep, Idle, Rx., Tx.). Currently, the WLAN card uses the M.2 connection slot. Is it possible to measure the power consumption from the power rails? How can I do it? Is there any quick guide or reference?

Best Regards//Roy

i.MX8M  #i.mx8MPlus

[iamRoy]

Thanks for your reply. I have read the document. It does not have enough information if I can measure the M.2 slot power consumption from the rail EXT_CN pins. Thanks anyway!

[jimmychan]

I think you could try to add the current meter to the L17 like the below.

Then you could measure the current different between using/disabling the wifi.

[iamRoy]

I really appreciate your support. Would it be possible for me to measure the current consumption of the Wifi if I modify the board as follows (image attached)?

1. Take 3.3V from EXP_CN pin 17. Pass it through an Ampere meter to TP104.

2. Remove the R452 to close disable the Q14 and provide voltage through VPCIe_3V3.

3. Provide 3.3V supply to PCIe_nDIS_3v3.

[jimmychan]

Yes.

[iamRoy]

I have made the above-mentioned modification, but somehow Wifi does not work at all after the modification (Provided 3.3V to TP104 from EXT_CN Pin-17, 3.3V to PCIe_nDIS_3v3/R33, and removed R452).

Do you have any idea what might have gone wrong?

[jimmychan]

https://www.nxp.com/design/design-center/development-boards-and-designs/i-mx-evaluation-and-developm...

You could download the design files of the EVK.

You could measure the current on the M.2 when wifi module is running.

[iamRoy]

Hi,

These documents look more useful to me. However, could you be more specific? How can I measure the current consumed by the M.2 while Wifi is running? I am sure your engineers have a clear idea of what/where to look. Please also mention if I need to change any hardware on the board.

Thanks

[jimmychan]

Yes, you could refer to this document.

i.MX 8M Plus Power Consumption Measurement