I am trying to test HMC863 along with HMC920 with the EVB. When I connect the default HMC920 EVB to my HMC863 board, the HMC863 is not functioning, and the VNEG and VGATE are both staying at -2.4V. Then I followed the application notes added a 255K resistor between VGATEB and VGATE to adjust the VGATE threshold around -0.8V. When I pullup SW and connect the PA again, VDRAIN stays at 0V and VGATE is still at -2.4V, it seems to me the HMC920 is not enabled. I am struggling how to use the HMC920 to bias HMS863.
From my understanding, HMC920 should be auto adjust the VGATE from -2.4 to -0.8V until HMC863 Idd reach 360mA because I set the Idain to 360mA with Rsense to 480ohms. Am I wrong? do I need to adjust both VNEG and VGATE to around -0.8V?