AnsweredAssumed Answered

ADL5375 output power

Question asked by takashi on Feb 6, 2012
Latest reply on May 21, 2012 by Sushmit

I'm now testing AD9779A-DPG2-EBZ evaluation board.

It has TxDAC AD9779A and IQ-modulator ADL5375-05 onboard.

Modulation data stream is generated from external FPGA and LO input comes from ADF4350-EB1Z.


Generated RF spectrum works as expected, but output power level seems lower than the value

in ADL5375 datasheet as LO frequency goes higher.


Measured values are as follows;

0dBm @750MHz

-3dBm @2GHz

-6dBm @3.65GHz


ADL5375 datasheet says Pout is between 0dBm and 1dBm in frequency range 0.45-3.5GHz.

I suppose Viq level is tuned in the evaluation board, and LO level from ADF4350-EB1Z is in appropriate level.


Any comments on the cause of loss and methods to improve S/N are highly appreciated.