I am a testing a high power amplifier IC(RF6886) for its s-parameters(gain and impedance matching) at a frequency of 145MHz. I have designed the board using eagle for this IC and got it manufactured through power PCB. The IC operates on a DC supply of 3.3V.
When I give supply to the board without connecting the vector network analyser, the IC draws a current of 0.3A and when I then connect the VNA, the current consumption increases to 0.9A and the supply voltage is observed to drop to 2.9V. Also, the VNA shows the gain as -15dB though the gain in dB of any amplifier should be positive. I have ensured multiple times that the IC and all the DC components as well the RF components have been soldered perfectly. What could be the cause for this to happen?