BJT (Bipolar Junction Transistor) and Mosfet (Metal oxide semiconductor field effect transistor) are both commonly used for amplification and switching applications. But they still have some significantly different propertites.
| BJT | Mosfet | |
|---|---|---|
| Type | PNP or NPN | N-type or P-Type |
| Device | Current Controlled Device | Voltage Controlled Device |
| Output controlled | By controlling base current | By controlling gate voltage |
| Temperature coefficient | Negative temperature coefficient | Positive temperature coefficient |
| Input Impedance | Low | High |
| Switching Frequency | Low | High |
| Preferred | Low Current Application | Hight Power Application |