So I'm trying to figure out the behaviour of transistors and which resistors to choose in order to control its modes. Let's assume that I'm using a resistor for all the connections of the transistor.
For Active mode, I did some math and I conclude that if I choose a BIG resistance in the base and SMALL for the collector and emitter then chances are that transistor will operate as an amplifier in active mode. Check the following to correct me if I'm wrong.
I noticed that some of my limits are wrong, but still, the idea stays the same. BIG R1 makes collector's voltage BIG and emitter's SMALL which is what I'm looking for to get closer to the inequation. Also, small R2 keeps collector's voltage BIG and SMALL R3 keeps emitter's voltage small.
Even if my conclusion is true, still its hard to choose resistor values to achieve that. For example, I tried R1=1K, R2=100, R3=100
but the transistor was in saturation. Then I changed R1=20K still in saturation. Then I changed R1=50K and finally, the transistor was
in Active mode with Ib=120μA and Ic=30mA .
Any other ways to achieve what I'm looking for??? I want to have control over the transistor and not making random stuff...
Thank you.
For Active mode, I did some math and I conclude that if I choose a BIG resistance in the base and SMALL for the collector and emitter then chances are that transistor will operate as an amplifier in active mode. Check the following to correct me if I'm wrong.
I noticed that some of my limits are wrong, but still, the idea stays the same. BIG R1 makes collector's voltage BIG and emitter's SMALL which is what I'm looking for to get closer to the inequation. Also, small R2 keeps collector's voltage BIG and SMALL R3 keeps emitter's voltage small.
Even if my conclusion is true, still its hard to choose resistor values to achieve that. For example, I tried R1=1K, R2=100, R3=100
but the transistor was in saturation. Then I changed R1=20K still in saturation. Then I changed R1=50K and finally, the transistor was
in Active mode with Ib=120μA and Ic=30mA .
Any other ways to achieve what I'm looking for??? I want to have control over the transistor and not making random stuff...
Thank you.