TPS2546: TPS2546 Eye diagram fail

Kai Hsiao

Guru 12675 points

Part Number: TPS2546

HI Sir

My system structure is SOC => 6inch trace => TPS2546 => 1inch trace => 20cm cable => USB2.0 connector

Figure 1 => without TPS2546 => USB2.0 eye pass

Figure 2 => with TPS2546 => USB2.0 eye pass

Do you have any idea about this issue ?

over 8 years ago

0 Donovan Porter over 8 years ago

TI__Intellectual 1920 points

Hi Kai,

Could you send me the pictures of the USB2.0 traces on your board please just so I can check?

Thanks,
Donovan

0 Kai Hsiao over 8 years ago in reply to Donovan Porter

Guru 12675 points

HI Donovan

FYI

Allegro.pdf

0 Donovan Porter over 8 years ago in reply to Kai Hsiao

TI__Intellectual 1920 points

Hi Kai,

The layout looks ok becase USB2.0 is pretty tolerant. I'm not sure why our device is affecting the Eye-Diagram so much. Here is an application report showing tests run using the TPS254x family of devices. The internal muxes should not have a big effect on USB2.0 performance.

Regards,

Donovan

Interface

Interface forum

TPS2546: TPS2546 Eye diagram fail