USB EMI Filter - USBUF01W6

[bsuthar]

Hello Friends,

I am Using STM32F303 MCU for my FULL Speed USB  communication board. Used interrupt transfer.

Board is going to use in Noisy Industrial environment.

So , Planned to use Shielded USB cable with EMI Chokes ( Both Side ).

Cable Length is 1.8 Mtr.

I plan  to use ESD / EMI ICs on the board before the MCU like ....USBUF01W6  "OR"  USBLC6-2SC6.

Any Suggestion Which would be better out of two ?

Regards,

Bsuthar

[RobK1]

Seeing as how the USBUF01W6 offers EMI filtering in addition to ESD protection, that would seem to me the better choice in this case.

Whether or not it is good enough for your application is a different matter, though.

[bsuthar]

Hey Rob

Concern with USBUF01W6 is , Higher capacitance on D+ / D- line.  Also, it adds unwanted Series resistor I believe.

[RobK1]

Just found out that STM have a USB Training. Its contents can be found here:

STM32_USB_training_Content.zip - Google Drive

It has a chapter on hardware design and, yes, it seems they do not want any series resistors in the data lines.

[bsuthar]

Hello Rob,

Thank you for sharing. It is Informative.

From the HW design Doc , They Mention to use USBLC6-4 instead USBLC6-2 for Self Powered.

I think we can use USBLC6-2 for Self Powered.

No specific reason I found for it.

With USB Type B connector , ID pin is not available. 

[FBL]

Hi @bsuthar 

You can check Table 13. ESD protection in AN4879 to find more about recommended ESD ICs.

I don't get your point about Type B connector and ID pin availability. 

[bsuthar]

Hello FBL,

Hardware design docs into STM32_USB_training_Content.zip - Google Drive

Suggests to use USBLC6-4SC6 instead USBLC6-2  for Self Powered Board , However , I could not retrieve the Reason...

May be because 4 Line Protection ( along with ID Pin )..

However , I used USBLC6-2 for D+/D- Line.

I have not used any separate ESD for VBUS line from the Host. I just connected it VBUS of USBLC6-2. ( See Schematic)

Await your valuable comments on that.

 

[FBL]

Hi @bsuthar 

We have two different implementations on different boards F303 eval board (MB1019) and F446 eval board  (MB1162)