Recently our customer designing HMC7044+2*HMC7043.
The output frequency is right,however HMC7043's RFSYNC can't work properly as below:
1.Test the pin DLOBYP2's voltage 1.97V,contrast with 1.8V on datasheet.
2.The reg 0X007D value is 00(Phase instability).The set reg 0X0050 as 0F,0X007D as 16,GPO pin shown as high(Phase stabilization).So we can find that 0X007D status is conflicting with GPO pin output.
3.Set 0X003 bit5 as 1,enable RFSYNC input,SYNC polarity as positive,RFSYNC input low level signal.The read REG 0X0091,value is 02 or 00 status.
4.Set reg 0X003 bit5 as 1 or enable RFSYNC input,we can find the pair HMC7043' clock phase is not fixed.
However if we set REG 0X003 bit5 as 0 or close RFSYNC input,the pair HMC7043' clock phase is fixed.
If possible please help to to analyze the RFSYNC status,thanks!