Transistor Circuits Design. March 8, 2010 by D Mohankumar Comments 25. Advertisement. ... T1 is a general purpose NPN transtior like BC 548. A potential divider comprising R1 and R2 bias the base of ...

If you are driving the transistor’s base with 0V to 5V while emitter is on 12V (Vbe is then -7V to -12V), you can’t fully turn the transistor off as there is some base current flowing at all ...

Circuit diagrams often show transistors in switching circuits. For an ideal NPN transistor, the switch-on voltage at the base is typically 0.6V (acceptable range is 0.6V to 0.8V).

• transistor, 2N2222A (Si type, NPN, Radio Shack part number 276-2009) • microammeter (0–50 000 µA range) How To Do It. 1. ... Draw a copy of the circuit diagram in your lab book.