A non-commercially available power amplifier may be required depending on the desired audio volume, power supply voltage, and passive speaker output power. Such an amplifier can be quite simply assembled on the basis of an integrated circuit TDA7560.
Necessary
microcircuit TDA7560, electrolytic capacitors 2200 uF × 50 V, 47 uF × 50 V, capacitors 0.1 uF - 7 pieces, capacitor 0.47 uF, resistors 10 kOhm, 47 kOhm, Circuit board, soldering iron, rosin, solder, connecting wires, air radiator with an area 30 square centimeters, 2 screws and 2 M3 nuts
Instructions
Step 1
This amplifier is designed to amplify sound in a car. It is designed for a supply voltage of 13.2 volts and produces an output power of 25 - 45 watts, depending on the load resistance (4 and 2 ohms, respectively).
Tin the conductive paths of the circuit board thoroughly with rosin. Solder the TDA7560 microcircuit to the board, then solder one lead of the blocking capacitors C3-C6 to pins 11, 12, 15, 17. The second terminal of these capacitors is the inputs of the 4 channels of the amplifier.
Step 2
Capacitor C1 and C8 is a power filter, solder them in parallel with the power circuit. Solder capacitors C9 and C10 to pin 16 and 10, respectively. When soldering electrolytic capacitors C8 and C10, pay attention to their polarity. The negative terminal is indicated on the capacitor case with a longitudinal strip, inside which minus signs are drawn. After that, solder the current-limiting resistors R1 and R2 to pins 4 and 22. Solder the capacitors C1 and C2 (0.1mkF) to the same pins of the microcircuit and the "ground" wire.
Step 3
Solder an insulated wire with a cross section of at least 4 square millimeters to pins 1, 6, 13 and 20. Solder a black wire to pin 1 and 13, this is the minus pin of the power supply. To pins 6 and 20 - a red wire, this is the “plus” terminal of the power supply. Connect the free terminal of the resistor R1 to the terminal of the power switch of the device with which you are going to use this power amplifier. Connect the free terminal of resistor R2 to the Mute button. Then solder pins 2, 8, 18, 24 of the microcircuit to the ground wire.
Step 4
Pins 3 and 5, 7 and 9, 17 and 19, 21 and 23 are the output pins of the power amplifier. When connecting car speaker systems, be sure to check the integrity of the insulation of the wires going to them. If any of these wires are shorted to ground in the car, the microcircuit may fail. Apply the audio signal to the input of the power amplifier (capacitors C3-C6) only through a shielded wire. Connect the braid of this wire to the “minus” of the power supply. After the end of the soldering, drill 2 holes in the radiator along the grooves on the microcircuit case and screw it to the metal plane on the microcircuit surface. Apply a thin layer of heat transfer paste between these surfaces.
