In this project, let’s learn about a simple Stereo Amplifier Circuit. This simple circuit is designed using 4 class B audio amplifier IC’s from Philips – namely TDA1554. Amplifier circuits are usually a pain to design, as you’ve to factor many elements into consideration.
The Design of Stereo Amplifier Circuit
Here is the circuit diagram of a powerful and high-quality stereo amplifier using IC TDA 1554. The circuit has only very few components. The circuit works best with a 4 Ohm speaker.
TDA1554 is a 4 x 11 watt integrated Class-B audio amplifier from Phillips. Since the IC can be operated from 12V it finds a lot of applications in-car audio systems. The TDA1554 has a lot of good features like thermal protection, reverse polarity protection, load dump protection, short circuit to ground protection, excellent ripple rejection, no switch ON/OFF thud, etc. The IC can be wired in single-ended or BTL (Bridge Tied Load) configuration and here in this circuit the later is used.
IC must be connected to a heat sink. A computer cabinet fan can also be used in addition(not necessary). Any way better the cooling better the performance. The circuit roughly draws 5A current at 12 V at full volume. So the power supply must be anything more than 5A. Up to 18 V can be used, which gives a bit more power boost. Commonly used is 12 V.
R1 39K 1/4 Watt Resistor
C1,C2 10uf 25V Electrolytic Capacitor
C3 100uf 25V Electrolytic Capacitor
C4 47uf 25V Electrolytic Capacitor
C5 0.1uf 25V Ceramic Capacitor
C6 2200uf 25V Electrolytic Capacitor
U1 TDA1554 Two-Channel Audio Amp Chip
MIS Heatsink For U1, Binding Posts (For Output), RCA Jacks (For Input)
If you like to build other audio circuits, you may start by trying our MOSFET amplifier collection, and then go on to build a hi-fi audio amplifier circuit. If you are still curious, please try our car stereo amplifier circuit as well.
Stereo Amplifier Circuit Diagram
Power supply for this power amplifier project.
A simple 12V,5A DC unregulated power supply is shown above. If 6A bridge is not available in your place you can make one using four 6A6 diodes and there will be no difference. 6A6 is a 6 ampere,600V silicon rectifier diode. LED D2 is added in the circuit as a power ON indicator and resistor R2 limits the current through it. Capacitor C7 is the filter capacitor while C8 is an AC bypass capacitor .S1 is the ON/OFF switch. Replacing the 9V transformer with a 12V transformer will increase the output voltage of the power supply to around 16V and you will get some extra power from the amp.