A transistor is based in order to make the emitter base. Figure 1.1 shows the effects of proper and improper DC biasing of an inverting amplifier. Biasing is the process of providing DC voltage which helps in the functioning of the circuit. In the next chapter, we will analyze each transistor. If an amplifier is not biased with correct DC voltages on the input and output, it can go into saturation or cutoff when an input signal is applied. The most effective method to bias the base of a transistor amplifier is using a voltage divider. Make Q-point independent of device parameters variation so that it does not shift. Bias establishes the DC operating point for proper linear operation of an amplifier. A weak signal is applied to the base of the transistor and an amplified output signal is obtained from the collector circuit. Region of operationĮstablish the operating point in the centre of load line, so that when we apply input signal the operating point does not move either in saturation or cutoff region.

Transistor operates in four different regions i.e Cutoff, Forward Active, Saturation, Inverse Active. So that while fixing operating point, it should provide proper dc conditions so that specific function is achieved. Base Resistor The terminal base of the transistor is connected with a high value of the base resistor. To obtain the operating point we have to use some circuits, these circuits are called biasing circuits. Base resistor Collector to base Biasing with a collector-feedback resistor Voltage-divider Above all the methods follow the same principle to obtain the required amounts of base and collector currents from VCC in the signal zero conditions. These values of current and voltage are expressed by the term called as operating point or quiescent point.

Its name comes from the fact that the two base resistors create a. The need of providing dc biasing for transistor is to obtain a dc collector current at a certain dc collector emitter voltage. We now introduce a transistors most common biasing technique, the voltage divider bias. Biasing is nothing but making use of resistors and power supply connected in such a way that to obtain collector emitter voltage and collector current.

Importance of transistor biasing