BC558 PNP Transistor in Pakistan

BC558 is a PNP transistor hence the collector and emitter will be closed (Forward biased) when the base pin is held at ground and will be opened (Reverse biased) when a signal is provided to the base pin. This is where a PNP transistor differs from an NPN transistor.

Features:

1. Bi-Polar PNP Amplifier Transistor
2. DC Current Gain (hFE) is 800 maximum
3. Continuous Collector current (IC) is 100mA
4. Peak Collector current (Ic) is 200mA
5. Emitter Base Voltage (VBE) is 5V
6. Base Current(IB) is 200mA peak
7. Available in To-92 Package

BC558 as switch

When a transistor is used as a switch it is operated in the Saturation and Cut-Off Region as explained above. As discussed a transistor will act as an Open switch during Forward Bias and as a closed switch during Reverse Bias, this biasing can be achieved by supplying the required amount of current to the base pin. A resistor is always added in series with a base pin to limit the base current. The value of this resistor (RB) can be calculated using the below formulae.

RB  = VBE / IB

Where the value of VBE should be 5V for BC558 and the Base current (IB) depends on the Collector current (IC).

Package includes:

• 1 x BC558 PNP Transistor