# Calculate NPN transistor [closed]

Assume I have battery with voltage $$\V = V_1\$$ and a PN2222 NPN transistor. I connect the C and B to the positive side of the battery and connect the E to the negative side of the battery. Assume that at the 3 wires, I have static resistances of $$\R_1\$$, $$\R_2\$$ and $$\R_3\$$ as in the diagram. How can I calculate the two currents through $$\R_1\$$ and $$\R_2\$$?

(The values like 1 V, 1 Ohm etc. and 2N3904 in the diagram are just example values; I don't know how to remove them.) simulate this circuit – Schematic created using CircuitLab

I am sorry for this dumb question, I am an absolute beginner, although I do understand math and some physics. In the data sheets of the PN2222, I could not find the necessary parameters like beta. But even if I knew beta, I would also need to know to some kind of inner resistance of the transistor, wouldn't I?

• There is an absolute requirement for answering such a question: Circuit diagram.
– LvW
Jul 2, 2022 at 9:16
• I described it. Or which tool can I use to paint one? Jul 2, 2022 at 9:19
• Beta ~= hfe. You can calculate the resistance from the slope of curves in the datasheet. Jul 2, 2022 at 9:19
• Kolodez, your decription is not clear. What means "I connect C and B to the positive side of the battery"? How many volts? When both are connected to a common node - short between C and B?
– LvW
Jul 2, 2022 at 11:14
• Edit your question and add a schematic. There is a schematic editor built into the editor. Learning starts with giving us a schematic diagram with battery voltage and resistor values. It's not that we can't handle the words, but the schematic removes ambuiguity! Jul 2, 2022 at 22:06

I simulated a simple circuit that has only a single base resistor and the transistor is saturated then it is not active. I also simulated it with a voltage divider pair of resistor at the base causing it to be active but the datasheet for an old 2N2222 does not give its range of beta. Then some of them with a high beta will not work unless the emitter resistor has an increased resistance. 