Base resistor for transistor switch Items tagged with Base resistor for transistor switch

Transistor is not used as amplifier but as a switch. We operate transistor in saturated (on state) and cut-off (off state) mode only.

And why 10K or 1K it actually depends on type of transistor used and collector current you want. Following are the exact parameters that defines your resistor value:

1. hfe/gain
2. Collector current
3. Drive voltage (voltage at pin)
4. Max drive current controller Pin ca... Read Compelte post