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ADF5355 problem

Question asked by joxer on Jul 2, 2015
Latest reply on Sep 6, 2017 by MRichardson


I have question about working of ADF5355 chip.

We use reference signal REFinA (Single-Ended Mode)  80.000 MHz in our board.

Power is as recommended in datasheet ADF5355 – ADM7150.

Necessary frequency of output signal is 5300 МHz, spectrum analyzer is connected to needle Complementary VCO Output  - RF outA−. Output RFOUTB is is disconnected by soft.

We can’t get the frequency above 4030 MHz. As Fundamental VCO range is   3400…6800 MHz, it is needed to set the meaning RF Divider = 1. When set RF Divider = 1 signal at the output of chip is absent. If set meaning RF Divider = 2, at the output of chip will be frequency 5300 MHz/2= 2650 MHz. Meanwhile signal Digital Lock at the output MUXOUT is in condition logical “1”, it means that VCO calibration goes successfully.

Which can be causes that we can’t use RF Divider = 1 at the frequency above than 4030 MHz and how we could solve this problem?

Is there possibility to chose manually 1 from 4 internal VCO?

Thank in advance.

Best regards,

Dudnik Konstantin