Ic set to a specific value when RF is OFF is the bias quiescent current of the transistor (Icq), to be able getting the linear gain of the amplifier when the RF is ON.
In this situation the RF input shouldn't be greater than a specific value, otherwise the transistor goes in the saturation and the amplification is not linear anymore.
But I still don't understand. in datasheet shows " VCE = 3.6 V, IC (set) = 30 mA (RF OFF),f = 460 MHz, Pin = 0 dBm". if RF OFF, why is there pin=0dBm? please see the attachedaras_1.
how to explain IC(set)=30mA in VCE ~IC curve? also what is the relationship between IC(about 500mA) and Icq(30mA).
This time I have attached the datasheet here. Thanks
Thanks vfone again.
After re-reading datasheet and your replies, I have more understanding about these parameters in datasheet. Also there are some other questions need to understand, I will study more.