DIY Electronic Project: Building a Low-Power Audio Mixer Using the TLC2264CN
Creating a compact and efficient audio mixer is a valuable project for audio enthusiasts and musicians who need to blend multiple audio signals into one output. Whether you're mixing different instrument signals, combining microphone inputs, or blending audio tracks, a low-power audio mixer can be a versatile tool. In this DIY project, we'll build a low-power audio mixer using the TLC2264CN operational amplifier, a component known for its low power consumption and excellent audio performance.
What is the TLC2264CN?
The TLC2264CN is a quad operational amplifier designed for low-power applications, making it ideal for battery-operated devices. It offers rail-to-rail input and output capabilities, which maximizes the signal swing and ensures high-quality audio performance. With its low noise and distortion characteristics, the TLC2264CN is perfect for audio applications, particularly in portable or energy-efficient devices.
Components Required
To build this audio mixer, you’ll need the following components:
TLC2264CN Quad Op-Amp: The core component for amplifying and mixing audio signals.
Resistors (10kΩ, 100kΩ): For setting the input gain and feedback loops.
Capacitors (10µF, 100nF): For coupling and decoupling purposes.
Potentiometers (10kΩ): To control the volume of each input channel.
Audio Input Jacks: For connecting various audio sources.
Audio Output Jack: For connecting the mixed output to a speaker or amplifier.
Power Supply: 5V to 15V DC, suitable for the op-amp.
Breadboard or PCB: For assembling the circuit.
Wires and Connectors: For connections.
Soldering Kit: For assembling the components.
Circuit Design
Input Stage: The audio mixer can accommodate multiple audio inputs, each connected to one of the op-amps in the TLC2264CN. The audio signals are first passed through coupling capacitors (10µF) to block any DC offset. Each input is then connected to a potentiometer (10kΩ), which allows you to control the volume of each channel independently.
Mixing and Amplification: The output from each potentiometer is connected to the non-inverting input of its corresponding op-amp in the TLC2264CN. The op-amps are configured in a summing amplifier arrangement, where the audio signals are mixed together. The gain of each op-amp is set using feedback resistors (100kΩ), ensuring that the mixed signal is properly amplified without distortion.
Output Stage: The mixed audio signal is taken from the output of the final op-amp in the chain. A coupling capacitor (10µF) is used to remove any DC component from the output signal before it is sent to the output jack. This ensures that the signal is clean and ready to be amplified by an external amplifier or sent directly to a speaker.
Power Supply: The TLC2264CN operates efficiently on a low voltage power supply, typically between 5V and 15V DC. This makes it ideal for battery-powered applications, allowing the mixer to be portable and energy-efficient.

Assembly and Testing
Assemble the circuit on a breadboard or PCB, starting with the power supply connections to the TLC2264CN. Connect the input jacks to the coupling capacitors and then to the potentiometers, which are wired to the op-amps. Ensure that each op-amp is properly configured in a summing amplifier arrangement.
Once the circuit is assembled, connect your audio sources to the input jacks and the output to a speaker or an amplifier. Power on the circuit and adjust the potentiometers to mix the audio signals. You should hear the combined audio signals through the output device, with the ability to control the volume of each input independently.
Applications
This low-power audio mixer is suitable for a variety of applications, including:
Portable Audio Systems: Mixing multiple audio sources on the go.
Home Recording Studios: Combining microphone and instrument inputs into a single track.
Live Sound Mixing: Small-scale live performances or practice sessions.
Conclusion
Building a low-power audio mixer using the TLC2264CN is a rewarding project that offers valuable experience in audio circuit design. The TLC2264CN’s low power consumption, combined with its high audio fidelity, makes it an ideal choice for creating a portable and efficient mixer. Whether you're a musician, a DIY audio enthusiast, or just looking to explore audio electronics, this project provides a practical and enjoyable way to expand your skills.
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