Hello every engineers !
Our customers had bought over 100pcs ADN2855 for their GPON products . They used the ADN2855 to detect the burst data . But there are over 15% chips will happen the data packet dropout situation .
For example , In the normal situation , they test the data in their test software . The up data is 100 , the down data should be 100 . But many chips 's down are only 98 , these chips also can work , but the test result is not very accuracy .
We had ruled out the keep condition or static electricity reasons ,
As below is the design schematics about ADN2855
When thsy test the BPD of the OLT optical module , Test the signal of ADN2855 DATAV_N , somtimes when the BPD in the high level ,the DATAV_N Will suddenly become high , (when the optical module is lighting , the status of DATAV is wrong , the data packet dropout will happen ) and the reset command can't control the ADN2855 .
So we think , maybe the circuit of ADN2855 or the circuit of optical module have some questions , or the clock of CDCE62005 have some questions . Please kindly help us analysis .
The below picture is the signal of DATAV_N