A 2 Watt mini audio amplifier circuit suitable for small pocket radios and other portable audio devices. This audio amplifier circuit is based on Phillips Semiconductors IC TDA 7052. This audio amplifier circuit will function down to 3 volts.
The IC TDA7052 is a mono output audio amplifier circuit in a 8-lead DI package (DIP). The device is mainly designed for battery-operated portable audio amplifier circuits. The features of the TDA 7052 include, no external components needed, no switch-on or switch-off click sounds , great overall stability, low power consumption (quiescent current 4mA), low THD, no heat sinks required and short-circuit proof.
The gain of this audio amplifier circuit, TDA 7052 is fixed internally at 40 dB. To compensate the reduction of output power due to low voltage supply the TDA7052 uses the Bridge-Tied-Load principle (BTL) which can provide an output of around 1 to 2 W RMS (THD = 10%) into an 8 Ohm load with a power supply of 6 V.
In the circuit the potentiometer is used to control the volume. Capacitor C1 and C2 are meant for filtering the supply voltage if a battery eliminator is used as supply source. For operations using a battery C1 and C2 are not necessary. The 8 Ohm Speaker can be replaced with an 8 Ohm headset.