I was designing an RF amplifier and I choosed the BFP196 transistor for its Ft.
As this transistor has 2 emitters, my doubt is which emiiter should I use if I need only one?
Considering that its a RF circuit, may I let the second emitter unconneted (open)?

 

Welcome to AAC!

I'd connect the unused emitter to the base. That would prevent it from doing anything untoward.

Thanks for asking your question. I wasn't aware of any discrete multiple emitter transistors.

 

Hello,

As far as I know the two emittors are internaly connected.
I see no evidence in the datasheets that the emittors can be used separately.

Bertus

 

In high-frequency amplifiers, the parasitic inductance of the emitter conductors (including the internal ones, with which the chip is unwired to the external terminals of the housing) is very important for the gain. Using two (wires) splitting reduces the value of inductances by half.

 

So it likely does not have two emitters, just two emitter connections, which should both be tied to the same node in the circuit.