A differential amplifier is a type of op-amp that has two inputs and one output. The output voltage is the difference between the two input voltages multiplied by the gain of the amplifier. Differential amplifiers are often used in applications where it is important to amplify the difference between two signals, such as in audio amplifiers and instrumentation amplifiers.
The main difference between an op-amp and a differential amplifier is the number of inputs. An op-amp has a single input, while a differential amplifier has two inputs. This difference in the number of inputs affects the way that the two amplifiers are used. Op-amps are typically used in applications where it is desired to amplify a single signal, while differential amplifiers are typically used in applications where it is desired to amplify the difference between two signals.
Here is a table summarizing the key differences between op-amps and differential amplifiers:
| Feature | Op-amp | Differential amplifier |
|---|---|---|
| Number of inputs | 1 | 2 |
| Output voltage | Gain of input voltage | Difference between input voltages multiplied by gain |
| Applications | Signal amplification, filtering, computation | Audio amplifiers, instrumentation amplifiers |
In addition to the key differences listed in the table above, there are also some other minor differences between op-amps and differential amplifiers. For example, op-amps typically have a higher gain than differential amplifiers. Also, op-amps are typically more susceptible to noise than differential amplifiers.
Despite these minor differences, op-amps and differential amplifiers are both very versatile and useful electronic devices. They are used in a wide range of applications, from audio amplifiers to instrumentation amplifiers.