I am using HMC7044 to generate 40MHz 、800MHz 、1200MHz and 2400MHz output. The output mode is CMOS and the schematic is as follows:
J7 is the test point.
The test results are shown in the following table, when output frequency is 2400MHz , the ouput power is too low.
The different output frequencies have the same configuration of other registers except for different frequency division ratios (register 0x00FB).
I only found the output signal power reference value of LVPECL in the datasheet,and the value differs greatly from my test results at 2.4GHZ.
I'm puzzled why my test result is to small at 2.4GHZ, is it correct?
And where can I find the reference values for CMOS mode output power?
Thanks in advance.