04 July 2012

Comparison between Junction transistor and JFET

Bipolar Junction Transistor (BJT)

1. Input resistance low

2. Transconductance very high

3. More noisy

4. Thermal Stability poor

5. Less costly

6. Sensitive to radiation

7. Bipolar device

8. Current controlled device since the base current controls the amount of collector current

Junction Field Effect Transistor (JFET)


1. Input resistance very high

2. Transconductance low

3. Less noisy

4. Thermal Stability good

5. more costly

6. Immune to radiations

7. Unipolar device

8. Voltage controlled device since the gate-source voltage controls the drain current. This is like vacuum tube.