Edifier 2.1 subwoofer circuit diagram produced by tda1521

The high-fidelity power amplifier IC TDA 1521 adopts a nine-pin single-in-line plastic package. It is a Philips 2×15W single-chip power amplifier integrated circuit. It has very few external components and is easy to use. It has short-circuit protection and noise suppression functions. The internal resistance of the power supply should be less than 4 ohms. , to ensure reliable operation of the load short-circuit protection function. Electrical characteristic parameters: (Vcc=±16V RL=8Ω f=1KHz Ta=25℃) 1. Power supply voltage: Vcc = ±7.5 -- ±20V Recommended value: ±15V 2. Output power: Po =2×12W (THD =0.5%) Po = 30 W in BTL form 3. Voltage gain: Gv = 30dB 4. Channel isolation: CT=70dB 5. Output noise voltage: Vno = 70uV (Rg=2KΩ) with large output power and two channels It has the characteristics of small gain difference and overheating, overload and short circuit protection. When using dual power supplies, eliminating the need for two audio output capacitors will result in better high and low sound quality. When using a single power supply, the power supply filter capacitor should be as close as possible to the power end of the integrated circuit to prevent internal self-excitation of the circuit.

ck="window.open(this.src)" alt="Click to see larger image" />

It should be noted that:

1. A heat sink must be installed, not less than 200mm×100mm×2mm.

2. As long as the power of the transformer is large enough and the heat is dissipated quickly, the effect will be very good.

3. Never connect the output terminal to the input terminal, otherwise the integrated block will be burned quickly.

TDA1521 Edifier 2.1 subwoofer circuit diagram . This amplifier has fewer components, is simple to make, and has good sound quality. It is very suitable for installation in active speakers. The effect is ideal and the cost is low, making it very suitable for beginners.

The power amplifier IC is TDA1521. When the power supply voltage is ±16V, the output power is 12W×2. At this time, the distortion is only 0.5%, and it has an on/off squelch function. This circuit is equipped with an equal loudness compensation circuit to improve the high and low sound effects at low volumes. W is a double eight-pin potentiometer with a center tap. It is connected with C1, R1, and C2 to form an equal loudness control circuit. The circuit is as shown below.

ck="window.open(this.src)" alt="Click to see larger image" />

Things to note when making: 1. The heat sink of TDA1521 must not be grounded, otherwise the IC will be damaged when it is turned on! Mica sheet insulation should be added between the IC and the radiator, and an appropriate amount of thermal conductive silicone grease should be added, and then the radiator should be grounded. 2. The resistance of the potentiometer W is 100kΩ, and its shell needs to be grounded. 3. The power connection from the filter capacitor to the ⑤ and ⑦ pins of the IC should be as short and thick as possible, and a layer of tin can be piled on the copper foil of the printed board.

After the production is completed, do a sound test and turn the volume potentiometer to the maximum. You can barely hear any noise when you are close to the speaker. I used a CD player to test it, and when connected to a floor-standing speaker, compared with the Pioneer M-850 amplifier, except that the power is slightly smaller, the sound quality is satisfactory, and the vocal performance is very clear and unambiguous.