NPN Transistor CE Amplifier

Amplifier made with an NPN transistor

Brief Summary
Using an NPN transistor in common-emitter configuration to make a high gain amplifier. You will need the waveform generators and oscilloscope of ExpEYES, and an NPN transistor(2N2222).
July 03, 2017
Jithin B.P.

Quick Start

The schematic is wired as shown in the diagram below. It is very similar to the schematic used for drawing the output characteristics.

The AC signal is connected to the base, through a capacitor so that the biasing is not affected.

Since the gain is high, we need a small input signal, smaller than the 80 mV available from WG. A divider network using 1k and 2.2k gives around 20 mV output and that is fed to the base. This input signal is monitored on A2. The DC operating point is decided by the voltage applied to the base through the 100k resistor.

By adjusting PV2, we can take the transistor between cut-off and saturation conditions. The value of PV2 is adjusted to get an output with minimum distortion. To improve it further, one can reduce the input signal, use a higher collector supply voltage instead of PV1, or use a transistor with a lower gain value.

Photograph: Transistor Amplifier

Screenshot of the UI

Screen shot of the input and output waveforms of Transistor Amplifier in CE configuration ExpEYES17: Transistor Amplifier