The amplifier is based on the TDA7385 integrated circuit. It is a power amplifier operating in the AB class with a power output of 35 W per channel. The amplifier module board has mute and off connectors.
• Output power: 4×35 W (RL=4 Ω, Vcc=14V).
• Short circuit, overheat and overvoltage protection,
• Stand-by and mute inputs.
• Power supply voltage: 12-18V DC.
• PCB dimension: 78×52mm.
• Electronic Kit – soldering required.
The TDA7385 chip has low distortion and low noise. Figure 1 and Figure 2 show the distortion characteristics as a function of output power and signal frequency. Figure 3 shows the schematic diagram of the amplifier. The TDA7835 integrated circuit is intended mainly for car amplifiers.
Assembly and test
The amplifier contains a small number of elements. Its assembly should not cause difficulties even for novice electronics. After the assembly, the amplifier is ready for operation. To switch It on, the ST-BY and MUTE terminals should be shorted to ground. The C5 and C12 capacitors should be soldered at the end, after screwing the heat sink, because mounting them may make it difficult to install the heat sink.
The amplifier can be loaded with a speaker of 4Ω or greater. It must be supplied with voltage from the 12-18V DC range.
C1-C4, C6, C9: 100nF
C5, C12: 47µF
C7, C8: 1µF
C10, C11: 1000µF
ST-BY, MUTE: goldpin connector 1×3pin + jumper
IN1-IN4: goldpin connector 1×4pin - 2pcs.
2-pin terminal block connector - 5pcs.
heatsink + fixing elements