Rongge

This Circut based on IC TDA7231 , Minimum voltage require 2 Volts and maximum voltage 15 volts . I recomended voltage is 12 volt DC. Power output 1,6 Watt with 4 Ohm impedance. See audio amplifier with IC TDA7231 below :

Overview: The AN7510/7520 series is a 0.5W to 3W BTL audio power amplifier IC. Equipped with a standby function and mute or DC  volume circuit, the series includes a lineup of single and dual output models. With simplified set design due to minimum  external components, this IC has a wide variety of applications. Features: Operating power sourcs voltage: 3.0V to 13.5V. Built-in standby function. Built-in mute or DC volume circuit. Circuit Diagram:  0.5W to 3W BTL audio power amplifier IC

The above is a simple amplifier circuit also has a minimal power output. By using only a few components and a single IC as the basis for the strengthening of the amplifier, this circuit has a power output of not more than 2.5 W and impedance or RL 8. Requires a minimum voltage of this amplifier is around 6V and 26V maximum voltage, the voltage must be DC or already rectified and filtered. Part List : R1 = 1R C1 = 0.1uF C2 = 100uF C3 = 0.1uF C4 = 5uF C5 = 500uF C6 = 0.1uF IC = ULN2280B , ULN2281B , ULN3784B.

Circuit which is also equipped with temperature sensors would protect the high temperature. However, in the above circuit which necessiatated the input of the amplifier / audio signal. The way it works is , if the amplifier circuit to work and ouput signal to be connected to this circuit , Fan 12V will work well. If the received audio signal this circuit does not exist , then the fan 12V die. And automatic circuit amplifier also not work and does not require refrigeration. Part List : R1_________________220K R2,R9,R10,12,13_____100K R3_________________2K4 R4_________________22K R5_________________1M R6_________________150R R7_________________2K2 R8_________________33R 4W R11________________10K C1_________________100pF C2_________________47uF 25V C3_________________100uF 25V D1,D2______________1N4148 Q1_________________MJE350 Q2_________________MPSA42 IC1________________7915 IC2________________LM35 F1_________________Fan 12 Volt

These amplifiers using IC KA2202 and KA2207, which has a power output of 2.3 Watt berimpedansi 4 ohms. Minimum supply voltage and maximum 5Volt 20Volt. See schematics and component list below. Part List  R1 = 100K R2 = 56R R3 = 56R R4 = 1R Use 1/4 Watt resistor C1 = 100uF C2 = 100uF C4 = 100uF C5 = 470uF C6 = 100nF C7 = 470pF C8 = 2,2nF C9 = 100uF U1 = KA2202 , KA2207