PHY interface of USB 2.0 core

[jenardo]

Hi all,
In case of implementing a USB 2.0 core, I wanted to ask about its PHY interface.
1) Is it possible to output D+ and D- directly from the FPGA ?
2) or is some kind of transceiver in between needed to convert high and low voltages to a differential one ?
3) What is an UTMI interface ? and where exactly is it located in a design ?

Thanks

 

[nand_gates]

Re: USB 2.0 core

For the UTMI refer to https://www.intel.com/technology/usb/download/2_0_Xcvr_Macrocell_1_05.pdf

 

[alzomor]

Re: USB 2.0 core

Hi,

You need 1st to check USB2.0 specifications @
https://www.usb.org/developers

If you could meet the Phy specs @ D+ & D- using your FPGA , so you can use it for direct connection , but I don't think it's possible.

all designs use a PHY interface layer which is UTMI or ULPI.

Regarding the UTMI you can think of ULPI also which is simpler.

UTMI is USB 2.0 transceiver macrocell Interface.
and ULPI is a low Low PIN Interface version of UTMI.

Salam
Hossam Alzomor
www(dot)i-g(dot)org

 

[verma.ind]

Re: USB 2.0 core

For what purpose we will use chirp counter in USB2.0 core? Can any body help me?

Thanks

 

[gck]

Re: USB 2.0 core

making D+ and D- sonnection by FPGA is not possible, for that i.e PHY layer chips are avilable u need to interface ur core with that.

 

[qasmi]

USB 2.0 core

Is there any controller IC that interfaces with the PHY Layer Chip or USB Transceiver, instead of implementing the core in FPGA?