This electronic circuit diagram is an audio power amplifier based on TDA8571J integrated circuit, class-B output amplifier with four amplifiers in a BTL configuration, each with a gain of 34 dB.
The maximum output power delivered by TDA8571J is 40 W into a 4 ohms load and is designed for car radio applications.
This microphone preamp schematic electronic circuit project is designed using the OP37 operational amplifier manufactured by Analog Devices and is effective, fixed-gain transformerless microphone preamp which amplifies differential signals from low impedance microphones by 50 dB, and has an input impedance of 2 k. Because of the high working gain of the circuit, an OP37 helps to preserve bandwidth, which will be 110 kHz. As the OP37 is a decompensated device (minimum stable gain of 5), a dummy resistor, RP, may be necessary, if the microphone is to be unplugged.
Using this the TDA7052 audio amplifier IC can be designed a very simple audio amplifier electronic project which can provide a 1 W maximum output power on a 8 ohms load .
TDA7052 is available in two types TDA7052B and TDA7052BT (Bridge-Tied Load which require 16 ohms load) which deliver a 0.5 W output power .
TDA7052 audio amplifier require few external components and has DC volume control.