Audio signal processing 1 W × 2-channel

Overview:

AN12942B is an one-chip IC for the stereo speakers which can output 1 W by 8 Ω, headphone amplifiers, line amplifiers, and electronic volumes. The AGC circuit is built-in to prevent the resonance or the vibration by the speaker’s energy and the clipping distortion what is  called "broken up sound".  Also the AN12942B is built-in power saving on/off function automatically detecting input signal to save the power of speaker  amplifier.

Circuit Diagram:

Audio signal processing

Audio power IC for mp3 Player

Overview:

The AN12941A is an amplifier IC for stereo  speakers which can output 1 W by 8 Ω or 2 W by 4 Ω. The AGC circuit is built-in to prevent the resonance  or the vibration by the speaker's energy and the  clipping distortion what is called "broken up sound."  of the speakers. Also, to reduce power consumption, AN12941A  has a built-in function which automatically detects the  input signal and can automatically enter power save  mode when there is no signal.

Features:

• Speaker amplifier is
• 1 W × 2-channel: 8 Ω, VCC = 5 V or
• 2 W × 2-channel: 4 Ω, VCC = 5 V
• Built-in AGC circuit
•  Prevention of the resonance or the vibration by 
• the speaker's energy and the clipping distortion 
• of the speaker by AGC at excessive input signal 
• (with AGC on/off switch).
• Built-in automatic power saving function
•  It detects input signals and switches on/off (with 
• the on/off switch for the automatic power saving).
• Operating supply voltage: VCC 3.0 V to 5.5 V/ 
• VCC_SP 3.0 V to 5.5 V

Circuit Diagram:

Audio power IC for mp3 Player

Auto Radio Amplifier Circuit

„ Features

• Dual 10 W audio power amplifier
• Built-in muting circuit
• Incorporating protection circuit
• Low frequency amplifier
• SIL-12 pin plastic package (Power-type with fin)

Circuit Diagram:

Auto Radio Amplifier Circuit

Stereo 50W Audio Power Amplifier

FEATURES DESCRIPTION

The LM4732 is a stereo audio amplifier capable of 2 typically delivering 50W per channel of

continuous The LM4732 has short circuit protection and a APPLICATIONS thermal shut down feature that is activated when the  The LM4732 also has an under voltage lock out feature for click and Each amplifier of the LM4732 has an independent KEY SPECIFICATIONS The LM4732 has a wide operating supply range from +/-10V - +/-40V allowing for lower cost unregulated power supplies to be used.

Features:

• Mute Attenuation 110dB (typ)

• PSRR 89dB (typ)

• Slew Rate 19V/μs (typ)

• Low External Component Count

• Quiet Fade-in/out Mute Mode average output power into a 4Ω or 8Ω load with less

• Wide Supply Range: 20V - 80V than 10% THD+N from 20Hz - 20kHz.

• Audio Amplifier for Component Stereo die temperature exceeds 150°C.

• Audio Amplifier for Self-powered Speakers

• Output Power/Channel at 10% THD+N, 1kHz 

• Audio Amplifier for Compact Stereo pop free power on and off.

• Audio Amplifier for High-end and HD TVs smooth transition fade-in/out mute.

• THD+N at 2 x 1W into 8Ω, 1kHz 0.01% (typ) bridge or parallel operation for 100W mono solutions.

Circuit Diagram:

Stereo 50W Audio Power Amplifier 

Three Channel Audio Mixer

General Description:

Above schematic is for a three channel audio mixer. That will provide an overall gain of one between the output and each input channel. Each input channel includes a single 0.1uf capacitor and 100-Kilohms resistor to provide an output impedance of 100K. The number of input channels to this audio mixer can be increased by adding more capacitors and resistors with same value as capacitor(0.1uf) and resistor(100K). The mixer should be located between the output of tone control circuitry and the input to the power amplifier. One input should be taken from the output of the tone control circuit, and the other inputs should either be grounded or taken from desired source.

Circuit diagram:

Three Channel Audio Mixer circuit diagram

Audio Mixer

General Description:

A new audio mixer circuit uses an LM3900 IC but is not a profesional audio dj mixer. The IC houses four integrated Norton amplifiers. The advantage of using the four op amps is that they only need a single power supply. Since this amplifier circuit is current controlled, the DC bias is dependent on the feedback coupling.The schematic diagram shows inverting AC-Norton amplifiers. The DC output must be set at 50 percent of the power supply. In this case, a maximum output can be achieved without distortion (also called symmetrical limitation through overdrive).In designing this mini audio mixer circuit diagram you can freely choose the value of the resistor R2 (100k in the mixer schematic). Set the AC voltage amplification factor through the ration of R2/R1. To set the amplifier gain correctly, choose the value of R4=2R2 (double the value of R2).Diagram 1.0 shows the 3-channel sound mixer circuit using three Norton-opamps. The input levels can be set by potentiometers P1 or P3. Furthermore, each input level can be trimmed with the help of trimmers pots P4 to P6 to adapt each input to the source. The resistors at the non-inverting inputs of the opamps work as DC bias and set the DC output at 50 percent of the power supply for this powered audio mixer. All three input signals are summed by the fourth opamp A4 through the resistors R3, R7 and R11. The commom volume level is cotrolled through the potentiometer P7. You can switch an input channel on or off through the switches S1 and S3. An input channel is turned off when its switch is closed. It is also possible to replace these mechanical switches with transistor gates. By doing so, you can build an analog multiplexer circuit that can be easily expanded by several inputs.

Circuit Diagram and PCB:

Audio Mixer Circuit Diagam

Audio Mixer Circuit digram

Audio Mixer layout

PCB Audio Mixer

35 W × 4-ch amplifier circuit diagram

General Description:

The AN7561Z is an audio power IC developed as the sound output of car audio (35 W by 4-ch.). A capacitor and resisitor to stop oscillation are built in between the output pin and GND so that a space saving of set is possible. Also, it incorporates a perfect muting circuit with out shock noise so that a shock noise design under the set transient condition can be made easily when used together with its standby function. In addition, it incorporates various protection circuits to protect the IC from destruction by GND-open-shortcircuit to ground and power supply surge which are the important subject of power IC protection. This IC will largely contribute to a high reliability design of the equipment.

Circuit Diagram:

35 W × 4-ch amplifier circuit diagram

Datasheet for AN7560: Download