This article shows how to design a basic 100 watt amplifier circuit using an IC LM12.
No expensive wiring or a large number of components are required.
Soon a few simple steps will lead to a world of superb and deep sound.
The 100 watt amplifier circuits compact size and efficient construction make it perfect for a wide range of applications.
An excellent 100 watt output is generated by enhancing audio signals using the LM12 IC design.
Circuit Working:
Parts List:
| Component | Quantity |
|---|---|
| Resistors | |
| 3.3k 1/4 watt | 1 |
| 2.2k 1/4 watt | 1 |
| 1k 1/4 watt | 2 |
| Capacitors | |
| Ceramic 2.7nF | 1 |
| Ceramic 100nF | 2 |
| Electrolytic 4700μF 100V | 6 |
| Semiconductors | |
| Diodes 6A2 | 2 |
| Diodes 6A4 | 4 |
| IC LM12 | 1 |
| Transformer 24V-0-24V 5 Amp | 1 |
| Inductor L1 4μF | 1 |
| Speaker 4Ω | 1 |
Using the LM12CLK integrated circuit for processing the Simple 100 Watt Amplifier Circuit with a Single IC is a simple and efficient design.
The IC has a strong output stage that can supply up to 150W of power at low impedances of as little as 2 ohms.
However, the circuit is designed to work with 4 ohm speakers for stability and safety providing an RMS power of 100W.
The transformer must produce 24 volts plus 24 volts of AC with a minimum current of 5 amps for mono or 10 amps for stereo in order to power the circuit.
It is advised to use a metal rectifier bridge unit with a heat sink rather than a bridge rectifier unit with four diodes.
14 turns are wound to create the output coil L.
18 wires without cores and 1 inch in diameter.
Performance is not impacted by the coils turn distance.
The circuit operates at its best when an exact resistor with a value of 1k and an output resistance rated for at least 2W of power are used.
It is required that the electrolytic capacitors have a 50V or 63V rating.
All of these elements work together to produce a strong and excellent audio experience.
With this project which has a small and effective circuit and which produces powerful excellent sound takes the sound system to the next level.
Simple to assemble enjoy the amazing sound quality.
The next stage is to use a single integrated circuit to build a custom 100 Watt amplifier circuit.
Formula:
The following formula represents a particular kind of amplifier circuit where voltage gain (Av) is expressed as follows:
Av = 1 + R3 / R2
where,
- The voltage gain of the amplifier is shown by Av.
- The voltage gain of an amplifier which enhances the input signal is greater than 1.
- An example of the feedback resistor that is connected between the inverting input and the op-amps output is R3.
- The gain resistor represented by R2 which is connected to both the op amps inverting input and ground.
Understanding the formula for the non-inverting op amp:
The desired voltage gain in a non-inverting op-amp configuration having better op-amp features which is as follows:
Av = 1 + R3 / R2
The formula indicates that the voltage gain is calculated by the ratio of the feedback resistor R3 to the gain resistor R2.
A higher R3 / R2 ratio is connected with a greater voltage gain.
Important points to remember:
This formula focuses on non-inverting op amp designs.
There are several formulas for inverting and for different amplifier designs.
The formula assumes a perfect operational amplifier with unlimited gain and limitless input impedance.
In actual circuits several factors can affect the actual gain achieved.
By selecting the right values for resistors R2 and R3 one can construct the voltage gain for the amplifier circuit.
How to Build:
For building a Simple 100 Watt Amplifier Circuit using IC LM12 involves several connections and assembling process:
Put first safety:
- Make sure there are the right tools and equipment with a safe working area.
- Check all component requirements one more time and follow by safety instructions.
Source of Power:
- Connect the transformer for the power supply to the circuit.
- Connect a 5A current for mono and a 10A current for stereo.
- Instead of using four diodes for the bridge rectifier use a metal rectifier bridge unit with a heat sink.
Coil Output (L):
- The output coil L is made by winding 14 turns of 18 wire around a 1 inch diameter without a core.
- It is not necessary to know the exact turn distance.
Integration of IC LM12:
- Connect the circuit board to the IC LM12 integrated circuit.
- For correct connections see to the datasheet or pinout information.
- Connect the electrolytic capacitors 50V or 63V and the accurate resistors 1k and 2W to the LM12s respective pins.
Connecting the Speaker:
- Connect the 4 ohm speakers to the amplifier circuits output stage.
- Confirm the correctness of every connection twice.
- Turn the circuit ON slowly while keeping an eye for any strange activity or indications of problems.
- To verify that the output signals match the expected values use the proper testing tools such as an oscilloscope or multimeter.
Conclusion:
Using the LM12 integrated circuit one can design a 100 watt amplifier circuit that uses very cheap components to produce a powerful audio amplifier.
High quality sound is produced by this circuit making it a great option for music lovers who want to improve their audio environments.
References:
Application Note 446 A 150W IC Op Amp Simplifies Design of Power Circuits