Privacy Policy
Transistor Basic Circuits » Electronics » Basic Circuits » Transistor Basic Circuits » Let's go... » Experiment 3 - Common Emitter Circuit

Experiment 3 - The Common Emitter Circuit

Consider the circuit shown. The circuit of the Experiment 1 is readily changed to obtain a proper common emitter circuit...

Common emitter circuit. (Enlarge)

Circuit diagram of a common emitter circuit.

The circuit is designed so that when pressing the push-button switch S1 of the transistor is saturated and completely switches through...

  • Pushbutton switch open...the transistor blocks and the LED lights up.
    (A current flows through R3 and LED1.)
  • Pushbutton switch closed...the transistor switches through and the LED goes out.
    (The current flows through R3 and T1.)

This is the opposite outcome of the first experiment, a proper common emitter circuit inverts the input signal!

A common emitter circuit is inverting

But what about the gain of the current in a common emitter circuit...?
Privacy Policy