In this lecture, we will discuss another topic of differential amplifier which is Differential Amplifier Configurations depend on various inputs and output combinations. So let’s start from the basics.
Differential Amplifier Configuration
A differential amplifier consists of two transistors.
Depending on the way of connecting the input to them and depending on the way of measuring output, there are four types of configuration of differential amplifiers.
The four important Differential Amplifier Configurations which we are going to discuss are as follows:
| Differential Amplifier Configuration | |
|---|---|
| 1. | Dual Input, balanced output differential amplifier |
| 2. | Dual input, unbalanced output differential amplifier |
| 3. | Single input, balanced output differential amplifier |
| 4. | Single input, unbalanced output differential amplifier |
The configurations listed above are defined according to the number of input signals used and the way an output voltage is measured.
Also Read: Differential Amplifier With Constant Current Source
If the two input signals are used; then the configuration is called as a “Dual Input” configuration otherwise it is a “Single Input” configuration.
If the output voltage is measured between two collectors, it is known as “balanced output” because both the collectors are the same at DC potential with respect to ground.
However if the output is measured with respect to ground, the configuration is called as an “unbalanced output”.
The images of all four configurations are shown in the above figure.
Also Read: Transfer Characteristics of Differential Amplifier
