1 W x 6 V Integrated Amplifier (ART510E)

The performance is excellent as you get 1 W with only 6 V and the number of external components is minimal: only two capacitors and a volume control.

The main features of this amplifier are:

Supply voltage: 6 V

Output power at 8 ohm: 1 W

Voltage gain: 40 dB

Typical quiescent current: 4 mA

Frequency range: 20 to 20 000 Hz

Typical harmonic distortion: 0.2%

Input Impedance: 100k ohm

OPERATION

There is not much to talk about this circuit given its simplicity. The TDA7052 integrated circuit has a preamplified stage inside which drives two counter-phase power stages with excellent performance, even with only 6 V power.

The only external components are the two source decoupling capacitors, which should be as close as possible to the integrated circuit power pin 1. The potentiometer P1 acts as a voltage divider, determining the signal intensity applied to the input and thus the volume.

ASSEMBLY

The schematic diagram of this amplifier is shown in Figure 1.

Figure 1

The small printed circuit board with only 3 components is shown in Figure 2.

Figure 2

The electrolytic capacitor is for 6 V working voltage and the other (C1) can be ceramic or polyester. It will be interesting to build the integrated in a socket in order to avoid heat in the welding process and to facilitate replacement if necessary.

The external speaker can be any size but must be capable of supporting 1 W of power.

USE

Power the circuit with 4 small, medium or large batteries and apply a signal to its input. Adjust the volume control (Pl) for a better playback.

Proving that the operation is normal, just use your amplifier.

If the signal source is a battery or walkman AM / FM radio, it is convenient to connect in parallel a 22 to 47 ohm x1/2 W resistor to the input to work as a load and thus avoid distortion. The volume of the signal source must be between the minimum and 1/4, just enough to drive it complete without distortion.