Wiring Schematic Diagram

The first stage of the amplifier is a differential amplifier based on transistors Q1 and Q2. Capacitor C8 is the dc input coupler, C1 R1 limits the input current and capacitor passes high frequency signals. The second stage is the stage driver consisting of transistors Q3 and Q4. Output stage is a complementary push-pull stage based MOSFETs IRF530 and IRF9530.Output attaches the loudspeaker with the inductor L1. Network consisting of R15 and C5 is designed to reduce noise. Capacitors C6 and C7 are the filters of the power supply. R6 is preset to adjust the quiescent current.

The diagram shown here is a MOSFET amplifier circuit 10W of sound that only requires a single source. Single railway material rarely used in power amplifiers class-B. However, for low power applications like this is very thin. Actually I have this circuit a old cassette player is still working and republish as it is. The BD512 and BD522 power MOSFETs is obsolete now and you can use any other power MOSFET game instead of them.



Transistors Q1 and Q2 are connected as a Darlington pair works as a preamp. R3 preset controls the quiescent current, while R2 provides. Output is coupled to the speakers through capacitor C4. Capacitor C5 is the power supply filter and C2 is the input DC decoupling capacitor.

Notes.

• The circuit can be assembled on a vero board.
• Use 30V DC for powering the circuit.
• Do not expect much performance from this amplifier.
• Capacitors C3, C4, C5 must be rated 50V and C2 can be 10V.
• Use a 8 ohm 15W speaker as load.

This circuit is an audio amplifier capable of delivering a decent output power with a minimum no: of the parties, with remarkable sound quality. The amplifier uses a single transistor and two MOSFETs and resistors and capacitors some feedback loop in a small scheme.This can bypass may offer a huge 18Watts into 8 ohm speaker or a speaker 30 W at 4 ohms.



For best performance and stability of some components, high-quality well-regulated DC power supply is needed. This is very essential to reduce noise and achieve a constant output power at different loads. A good voltage regulator capable of delivering CC over 2 Amps @ 40V can be used.You can expect a power supply design very soon here in the food section.

An 30 Watt audio amplifier circuit with TDA2040 shown here. TDA2040 is class AB amplifier monolithic integrated audio Pentawatt available in the package. The IC has a low harmonic distortion, cross low over the distortion and has a built in short circuit protection circuit.

In the circuit of two TDA2040 ICs are connected in BTL (bridge tied load) configuration to provide an output of 30W into a 8 ohm speaker to + /-16V DC. Capacitor C1 is a decoupling capacitor DC input. Network consisting of components R2, C4, R3 provides information to IC1 as R7, C6, R8 network provides information of IC2. Red C5, C9 and R5, R9 provides high frequency stability. Capacitors C2, C3 filters positive power rail while the capacitors C7, C8 filters negative power rail.

TDA2822 is a monolithic integrated audio amplifier can be configured in stereo mode or bridge (BTL). The IC has low crossover distortion, low quiescent current and is available in 16 pin DIP package power. The TDA2822 may be operated from a supply voltage range of 3V to 15V. The main applications are headphone amplifier TDA2822, portable audio, radio, mini headphones, preamp etc. The IC can deliver an output power of 0.65W per channel into a 4 ohm speaker 6V @ HV mode 1.35 W stereo and a speaker 4 ohm high voltage supply 6V @ bridge mode.

IC TDA2822 stereo set shown in Figure 1. The left channel input is applied to the noninverting input (pin 1) of the first built in the amplifier stage and the right channel input is applied to the noninverting input (pin 16) of the second amplifier. The inverting input of these built in amplifiers are grounded separately using 1000uF capacitors (C5 and C6). The amplified outputs (left and right) are available at pins 6 and 11 of the IC. The outputs are attached to the respective speakers, using capacitors C1 and C2 respectively. The branch capacitor resistance (ohms 0.1uF and 4.7) connected via the speakers are designed to improve stability and avoid high frequency oscillations. C7 is the power supply filter capacitor.

The output of the amplifier TDA2822 can be increased by use in mono using the bridge configuration shown in Figure 2. The audio input is applied to the noninverting input of amplifier built for the first time. The non-inverting input of the second built-in amplifier to ground. The inverting input of these amplifiers are based with the C9, C11 capacitor branch. Branches R5, R6 C8 and C10, are to improve stability and avoid high frequency oscillations. Capacitor C12 is used for filtering the power supply