6W amplifier using TA7222AP

john April 7, 2010 9 Comments
Description. Here is the circuit diagram of a 6W amplifier using the TA7222AP from Toshiba.TA7222AP is an excellent integrated audio amplifier which can deliver 5.8W to a 4 Ohms load at 12V supply voltage. The IC has very good features like, muting function, low distortion, high ripple rejection, short circuit protection, thermal shut down etc. This amplifier can be operated from 8 to 12V and this makes it ideal for car radio applications. Circuit diagram. Notes. The circuit can...
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Stereo balance indicator

john April 7, 2010 1 Comment
Description. This is one of the simplest stereo balance indicator circuit that you can have. The circuit will give a visual indication (using two LEDs) proportional to the difference in balance between the left and right channels of a stereo system. The circuit is based on a uA741 opamp IC. The IC compares the signals from the two channels and when both signals are in balance, the output of the IC will be steady and the LEDs will glow...
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Dynamic microphone amplifier using transistors

john April 7, 2010 3 Comments
Description. Here is the circuit diagram of a simple dynamic microphone amplifier using two transistors. The amplification factor of this circuit is around 150 and can handle signals from 50Hz to 100Khz.These features make it ideal for audio applications. The audio signal from the microphone is coupled to the base of Q1 via the capacitor C1 and resistor R3. Q1 works as a preamplifier here. The preamplified signal will be coupled to the base of Q2 for further amplification....
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40W audio amplifier

john April 7, 2010 8 Comments
Description. This is a very excellent 40W power amplifier design using TDA2030 IC and two transistors. The circuit employs only few components and does not require a dual power supply. The input signal is coupled to the non inverting input of TDA2030 through the DC decoupling capacitor C5. The TDA 2030 performs the major part of voltage amplification. As the IC performs amplification, the power supply current to the IC varies according to the input signal. The variations in...
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Preamplifier for dynamic microphones.

john April 7, 2010 3 Comments
Description. Here is a low noise preamplifier design for dynamic microphones. The circuit is based on the uA739 IC from Fairchild Semiconductors. uA739 is a dual audio operational amplifier with high gain and excellent stability. Out of the two opamps available in the IC, only one is used here. The audio signals from the microphone are coupled to the non inverting input of IC1 through the capacitor C1 and resistor R1. C1 performs input DC decoupling. The R1, C2...
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FET based audio preamplifier.

john April 7, 2010 7 Comments
Description. This is the circuit of a based audio preamplifier which has very low noise. One FET and one BJT are used in this circuit. The audio signal to be amplified is coupled to the base of FET Q1 using capacitor C1 and resistor R3.Base of transistor Q2 is coupled to the drain terminal of FET Q1. Transistor Q2 provides additional current gain. The final signal will be available at the collector of Q2.Capacitor C3 provides necessary negative feedback,...
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Jet engine sound generator

john January 18, 2011 21 Comments
Description. This jet engine sound generator circuit is based on the sound generator IC HT2844P from Holtek Semiconductors. This particular IC can make four sounds namely low speed sound of jet engine, high speed sound of jet engine, missile sound and machine gun sound. Each of these sounds can be activated by connecting the pins 12, 13, 14and 15 to ground by using the respective push button switches. Resistor R3 can be used for manually increasing or decreasing the...
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250mW audio amplifier

john April 7, 2010 11 Comments
Description. Here is a very simple three transistor audio amplifier circuit that can deliver 250mW to a 8Ohm speaker. Complementary transistors BC337 and BC227 (Q3 and Q2) are used as the output pair. Transistor Q1 (BC 547) acts as the preamplifier.POT R5 can be used as a volume control. Capacitor C1 decouples the DC from the audio source. Resistor R2 ensures better stability for the amplifier.This amplifier is very suitable for application in small radio sets and as a...
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10W amplifier using TDA2003

john September 28, 2017 22 Comments
Description. Here is the circuit diagram of a 10W audio amplifier using the popular TDA2003 IC from SGS Thomson. The IC can easily deliver 10W to a 4 Ohms load at 18V DC supply voltage. The IC can be also operated from 12V and that makes it applicable in car audio systems. The useful features of TDA2003 include short circuit protection between all pins, thermal overload protection, low harmonic distortion, low cross over distortion etc. The circuit given here...
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Single transistor audio mixer.

john April 7, 2010 3 Comments
Description. Many audio mixer circuits have been published here. But I think, this one is the simplest of them. This very simple audio mixer circuit uses only one transistor. The base emitter junction of the transistor is biased by the diodes D1 and D2.The signals to be mixed are directly coupled to the base of Q1.Each input lines are current limited by using a 33K resistor. With the used component values the collector current is around 1mA. Circuit diagram...
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