I am using HMC586 sample part to excite a patch antenna. The VCO is given 5V supply via 7805 regulator. The VCO schematic is designed as per the EVAL-HMC586LC4B Kit design files. The Vtune of VCO is controlled using Digital to analog converter AD7533 and Arduino Mega 2560. I am also using a diode in series to vtune port to discard the negative voltage if any generated. The Vtune gets shorted to ground after few days of use. Not able to find the issue. Kindly Help!!
[edited by: Aman777 at 5:21 AM (GMT -5) on 22 Dec 2021]