Custom hardware, cannot enumerate, VID/PID=0x0000

[Anonymous]

I'm working on a custom board. After connecting the USB cable, Windows displays a  "USB Device not recognized" message. In device manager, the VID/PID pair are both 0000. I checked this by reading the "Device Instance Path" field. 

   

I checked the steps given in AN15456. I've checked all the voltages and they are all fine. The rest and Wakeup pins are also correctly set (Wakeup is pulled high). I am also getting the 12 MHz output wave on CLKOUT. The application note suggests that since Wakeup is high, SDA and SCL should be pulled up, which is also done. I do not have an EEPROM on the board so this matches the initial test sequence in the application note. Yet, I cannot get the chip to enumerate. 

   

Is it possible that this is a problem with the chip itself? Should I replace it? Or am I missing something simpler?

[Anonymous]

Hi,

   

     Please create a tech support case (MyAccount -> MyCases) so that one of our engineers can review your schematic.

   

Thanks

   

Prajith

[Anonymous]

If you use USB in High speed, make sure the power supply of USB interface is in good quality, using effective filter.

[Anonymous]

 OK I think the problem was with the crystal I was using. I used a function generator and the device enumerated correctly.

   

Thanks.