This configuration is known as common-emitter configuration because here the emitter is used as the common negative terminal for the input base signal and the output load. In other words, the emitter terminal becomes the reference terminal to both the input and output stages (meaning common to both the base and collector terminals). Common emitter […]
Electronics Theory
Understanding Common Base Configuration in BJTs
In this section we are going to analyze BJT common-base configuration, and learn regarding its driving point characteristics, reverse saturation current, base to emitter voltage and evaluate the parameters through a practical solved example. In the later parts we will also analyze how to configure a common-base amplifier circuit Introduction The symbols and annotations utilized […]
Bipolar Transistor (BJT) – Construction, and Operational Details
A bipolar transistor or a BJT is a 3 terminal semiconductor device which is able to amplify or switch small signal input voltages and currents to significantly larger output signal voltages and currents. How Bipolar Junction Transistor BJTs Evolved During 1904–1947, the vacuum tube was unquestionably the electronic device of great curiosity and growth. In 1904, […]
Voltage-Divider Bias in BJT Circuits – More Stability without beta Factor
Biasing the terminals of a bipolar transistor using a calculated resistive divider network for ensuring an optimal performance and switching response is called voltage divider biasing. In the previous bias designs that I have explained the bias current ICQ and voltage VCEQ were a function of the current gain (β) of the BJT. But, as we […]
Emitter-Stabilized BJT Bias Circuit
A configuration in which a bipolar junction transistor or a BJT is reinforced with an emitter resistor for enhancing its stability with regards to changing ambient temperatures, is called an emitter stabilized bias circuit for BJT. We have already studied what is DC biasing in transistors, now let’s move ahead and learn how an emitter […]
Load-Line Analysis in BJT Circuits
So far we have been studying BJT analysis dependent on the level of β over their corresponding operating points (Q-point). In this discussion we will check out how a given circuit conditions can help in determining the possible range of operating points or Q-points and in establishing the actual Q-point. What is Load Line Analysis […]
