Newbie level 6
I have come across a problem while measuring a Doherty power amplifier, designed with CGH40010F transistors. I have biased the transistors and checked them properly before moving towards the RF analysis. The RF analysis was having a problem as it was not showing the desired gain. After that when I turn off all the setup sequentially and then check the transistor using a digital multimeter I found that the gate to source and gate to drain was showing 50 ohms which should be open load in DC condition. If I turn on the setup again for DC analysis then I found out that the drain current of the class AB carrier amplifier is flowing without the control of the gate voltage. Therefore I want to consult with you that what may be the problem with this kind of behavior.