In simple words, a power amplifier increases the strength of an input signal and delivers it to the output circuitry. A power amplifier is represented in terms of BJT or FET in schematics and circuit diagrams. However, the most common representation of any amplifier is a “triangular shape”. Amplifier symbol. 2. Power amplifier stages
The amplification stage performs the main signal-strengthening function of the power amplifier. Also known as the voltage amplification stage, this stage is responsible for the voltage gain of the power amplifier. The voltage amplification stage does not provide enough current to drive the output stage.
Power amplifiers are the hidden power behind electronics. They transform faint electrical signals into robust outputs, driving everything from concert hall speakers to medical imaging equipment. With various types available, each offering a unique balance between efficiency and distortion, power amplifiers ensure clear and impactful results. 1.
Also known as the voltage amplification stage, this stage is responsible for the voltage gain of the power amplifier. The voltage amplification stage does not provide enough current to drive the output stage. The primary function of the driver stage is to provide sufficient current gain that controls the output stage of the power amplifier.
Transformers, common collector transistors (emitter-follower), and capacitors are used for coupling in power amplifiers. The output stage or final stage can consist of current limiters, filters, DAC (Digital-to-Analog Converters), and feedback. At last, the output stage is responsible for delivering the power to the load. 3.
The above-mentioned linear and switching power amplifiers use analog techniques for amplification. A digital amplifier implements DSP (Digital Signal Processing) techniques to amplify the signal and generate a digital output. However, digital output can be converted to analog by a DAC at the output stage.