ds92LX2122 eye diagram test

Jeff Wang100039

Intellectual 2050 points

Other Parts Discussed in Thread: DS92LX2121, DS92LX2122

Hi,

customer use DS92LX2121 and DS92LX2122 for Car GPS. cable distance about 50cm. now want to set a suitable EQ for DS92LX2121. How can we get DS92LX2122 after EQ eye diagram? (for 913/914, 925/926 have CML output pin, we can do the test).

over 11 years ago

0 Dac Tran over 11 years ago

TI__Expert 7395 points

Hi Jeff,

The same CMLOUT method applies for measuring the eye opening on DS90LX2122. There is a mode that provides a loop through output of the recovered forward channel (without back channel) after EQ equalization and prior to the CDR block. The loop through driver is available on RES pin 38 (CMLOUTP) and pin 39 (CMLOUTN). To enable the CMLOUT pins to measure the high speed eye opening, program register address 0x3F’h bit [4] = 0 (CMLOUT=enabled).

Dac Tran

SVA / APPS

0 Jeff Wang100039 over 11 years ago in reply to Dac Tran

TI__Intellectual 2050 points

Hi Dac,

Thank you.

Interface

Interface forum

ds92LX2122 eye diagram test