The article discusses how to build a 12 watt amplifier circuit using the IC TDA2030.
The TDA2030 is a widely used integrated circuit IC for audio amplification.
It is a monolithic audio power amplifier in a Pentawatt package designed for use as a low frequency class AB amplifier.
Circuit Working:
Parts List:
| Category | Component | Value/Type | Quantity |
|---|---|---|---|
| Resistors | 22k | 1/4 watt | 1 |
| 680k | 1/4 watt | 1 | |
| 1.8Ω | 1/4 watt | 1 | |
| 4.7k | 1/4 watt | 2 | |
| Potentiometer | 22k log | 1 | |
| Capacitors | Ceramic | ||
| 100nF | 1 | ||
| Electrolytic | |||
| 2.2µF 25V | 1 | ||
| 10µF 25V | 1 | ||
| 1000µF 25V | 1 | ||
| 100µF 40V | 1 | ||
| Semiconductors | Integrated Circuit | TDA2030 | 1 |
| Speaker | 8Ω | 1 |
Utilizing a 24V power source, this amplifier circuit using TDA2030 can deliver an output power of approximately 8W rms into an 8 ohm speaker, maintaining low distortion less than 0.1 percent THD.
When paired with a 4 ohm speaker, the output power increases to around 12 watts rms, with distortion roughly quadrupled albeit still within the lower range.
The circuit is functional with lower output voltages, such as around 9V but this will result in a reduction of the maximum output power.
Incorporating a TDA2030 integrated circuit, this circuit features a contemporary device that offers faster and more basic operation compared to most older counterparts.
Formulas and Calculations:
The voltage gain of a non inverting amplifier circuit may be determined using this formula, which is particularly useful for operational amplifiers with certain configurations:
Gain = (1 + R3 / R2)
where,
- Gain: This is the op amp circuits output voltage (Vo) divided by the input voltage (Vi).
- Stated otherwise, it indicates the input signals amplified strength by the circuit.
- R3: This is the resistance value that is linked between the op amps output and an inverting input terminal resistor (sometimes marked “-In”).
- R2: The resistance value that separates the op amps inverting input terminal from ground (often denoted by the letter “GND”).
Calculations:
R2 4.7k: This indicates that there is 4.7 kilohms of resistance in the resistor that is linked to the inverting input and ground.
R3 4.7k: This indicates that there is a 4.7 kilohm resistance in the resistor that is linked between the output and the resistor at the inverting input.
Using the formula:
R2 = 4.7k and R3 = 4.7k, the gain becomes:
Gain = (1 + 4.7 kΩ / 4.7 kΩ) = (1 + 1) = 2
Meaning:
This specific op amp circuit set up with these resistor settings will increase the input voltage by a factor of two because the gain is 2.
Stated otherwise, if the op amp functions within its linear range, the output voltage will have double the amplitude of the input voltage.
Key Points:
Particularly, non inverting op amp topologies are covered by this formula.
The formula for inverting setups is a little bit different.
In this simplified approach, it is assumed that the op amp itself has a very large open loop gain ideally infinite.
The potential advantage is provided by this formula.
The actual gain in real circuits may vary slightly due to several factors such as op amp characteristics and component tolerances.
How to Build:
Mentioned below is the circuit description:
- Connect the positive and negative terminals of the power supply to the corresponding pins of the TDA2030.
- It is recommended to use a dual power supply with a voltage range of ±12V to ±18V.
Input Stage:
- Connect the audio input signal to the non inverting input pin 3.
- The inverting input pin 2 is grounded.
- R1 and C1 form a high pass filter providing stability and reducing the DC offset.
- R2 and R3 form a voltage divider for feedback setting the gain of the amplifier.
- The gain is calculated as (1 + R3/R2) explained in above formula.
Output Stage:
- R4 provides stability and ensures proper biasing.
- C2 blocks any DC component from reaching the speaker.
- C3 and C4 are part of the output filter network.
Speaker Connection:
- Connect the positive lead of the speaker to the OUT pin and the negative lead to the GND pin.
- C3 and C4 help in filtering out any remaining AC components ensuring a clean output signal.
Conclusion:
This simple amplifier circuit using TDA2030 is a starting point, and values of components may need adjustments based on specific requirements.
Additionally, proper heatsinking for the TDA2030 may be necessary especially if operating at higher power levels.
Always refer to the datasheet of the TDA2030 for detailed information and recommended application circuits.
References
Design and implementation of a high performance AB-class amplifier using TDA2030