Simple 100W HiFi Audio Amplifier Circuit Diagram

This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet. Enhancer materials must be common and accessible to everyone. Construction and adjustment must be simple. The amplifier must be economical and efficient. The whole circuit is based on two Darlington output transistors that with the help of the input circuits give almost perfect results.

Technical specifications

Output power: 100W (RL = 4Ω, K = 0.1%) or 70W (RL = 8Ω, K = 0.1%) (continuous sinusoidal signal)

Power in relation to frequency: <10Hz-100KHz at 100W

Distortion: 0.1% at 20Hz-20KHz at 100W

Intrinsulation: 0.28% measured at 40Hz and 10KHz at a 4: 1 ratio and Pa = 100W

Signal/Noise (SIN): 70 dB

Input sensitivity: 0.775V

Input resistance: 100KΩ

Output resistance: 0.052 Ω (in 1KHz)

Minimum load: 4Ω

Power supply: 80V symmetrical (+ 40V, 0, -40V)

Current consumption: 2.5A max at RL = 4Ω

Peak current: 50mA

The circuit

The input stage, is a differential amplifier with main elements the transistors T1 and T2. Then we have a lead step with T4 whose collector is connected to the T3 emitter. This works like an adjustable Zener diode and regulates the resting current. The final step follows with two completely complementary transistors T7 and T8 (Darlington).

An advantage of the symmetrical voltage, is that the electrolytic capacitor is avoided at the circuit.

The amplifier has a fairly high input resistance that exceeds 100KΩ since before C4 we have R2, and since the input resistance of T1 is too high.

Negative feedback (both for DC and for AC) we have with resistance R6. The DC negative feedback section produces almost zero potential at the output. The feedback section AC determines the amplification and is dependent on R6, C4 and R3. The amplification is determined by the formula:

Uo/Ui = (R3 + R6)/R3 = 3420/120 = 28.5

The stage with T4 leads the T7 and T8, but because they are darlington they need very little base current, so for T4 we do not need a heatsink.

Transistor T3 together with resistors R18 and R19 stabilizes the output current of the output transistors. The voltage drop on R18 and R19 is determined by the position of P1 because it controls the collector voltage from the T3 transmitter. R11 in conjunction with C5 capacitor increases the AC boost of the drive.

The heart of the output stage is the Darlington transistors BDX66 and BDX67. At 25°C this series has the following characteristics:

    • Collector collector voltage: 100V

    • Max Collector Current: 16A

    • Maximum power absorbed: 150W

If the collector current becomes 10A then the collector voltage from the transmitter becomes 2V and the amplification at DC is about 1000. When the collector current is 5A then the voltage is between 0.4V and 0.5V and the amplification is about 4000.

With these characteristics these transistors are ideal for such circuits. Regardless of how "good" the transistors are, they need protection from short circuits.

The voltage drop on the collector resistors R18 and R19 gives us the magnitude of the collector current through the transmitter. If the current passing through the resistors R18 and R19 passes a certain limit, then they will start to drive the transistors T5 and T6 since the voltage on the dividers R16, R14 and R15, R17 parallel to R18 and R19. Thus the currents passing through the diodes D2 and D3 will reduce the base currents of T7 and T6, which will also reduce the collector currents.

The various other elements R and C serve different purposes. C1 limits the input bandwidth. This avoids a portion of noise. C3 is responsible for 3dB at 100KHz, that is to say, it is inclined to the characteristic of the frequency response. C6, C7 and C8 are Miller capacities. C9 and R20 stabilize the output. The C10 / R21, C12, C11 / R22 and C13 cut off the various peaks at the RF frequencies coming from the power supply.

Technical specifications

The circuit has no difficulty and its construction is relatively easy. With some luck, the amplifier can give 120W of power at 4Ω, but unfortunately the deformation reaches about 1%. But at 100W (again at 4Ω) the deformation is less than 0.1%.

From the following figure we see that the deformation remains constant and is less than 0.1% at frequencies from 40Hz to 20KHz. For full performance the input must be greater than 0.775V. This level is given by almost all preamplifiers. If a higher output device is used then a 10KΩ potentiometer must be fitted at the input of the amplifier.

The power supply

It is known that the performance of the amplifier depends on the quality of the power supply. The amplifier needs a symmetrical voltage of ± 40V. At full power (100W at 4Ω) the current is 2.5A and at load 8Ω with power 70W the current is 1.1A. For economy and simplicity, we use a non-stabilized power supply. By its nature, however, such a power supply will have a fluctuation in voltage.

If the power supply at full power output is 40V it means that with less power the supply voltage will tend to increase. However, since the output elements have a maximum operating voltage of 100V, which means ± 50V, the design should be done so that these limits are not exceeded. For this reason, we define the power supply voltage to ± 46V so that we also have a safety margin. However, the ± 46V only leaves a margin of 6V between maximum and minimum load. However, this means that the internal resistance of the power supply must be very small. A good way to get a little resistance is to use a good transformer.

Given the good transformer, a bridge-rectifying bridge and some electrolytic capacitors and we have the power supply we need. The fuses on each power line are used to protect the circuit from short circuits, because the T7 and T8 protection circuits are only short-lived until the fuses are blown. For stereo performance we need two amplifiers and therefore two power supplies.

Construction

Resistors R18 and R19 must have a PCB spacing of at least 5mm. This generates a good bleed and hence good heat dissipation. Transistors T7 and T8 as well as capacitors C7 and C8 are mounted on the heatsink.

The heatsink must be 1.2 ° C / W. If a heat-conducting paste is applied on both sides, then a heatsink with 1.8 ° C / W is sufficient. It is known that if more than one transistor is placed on a heatsink then we have to divide the thermal resistance of the heatsink with the number of transistors. Therefore, if both transistors (T7 and T8) are placed on a heatsink, then the type should be 0.6 ° C / W or 0.9 ° C / W.

In no case should there be direct contact of the transistor with the heatsink, because the collector is connected to the transistor cover and thus would cause short circuits. For this reason, insulators such as, for example, Mica.

Before connecting the capacitors C7 and C8 (see Fig. 4), insulate their terminals by placing eg. Plastic macaroni.

The connections to the printed circuit must be made with the shortest possible copper wire.

The input jack must be connected to an AF cable in the printed circuit (coaxial cable should be grounded). The best way to connect the ground to the amp printed box is to ground the input jack. The cable and the plug must be positioned as far as possible from the other components and cables to reduce the possibility of back-up and noise from the 220V network.

The two windings of the secondary are completely separate. That means four wires will remain in our hands. To see where we connect each one we get two in luck and unite them. Then we measure the voltage in the other two. If the voltage between them is 60V AC, then connect the two wires together with the earth of the power supply and the other two in the remaining free points. If the voltage is 0V, then we need to change one of the edges we've joined with a free one. Electrolytic capacitors must be attached (due to size) to the PCB with a plastic collar or the like.

Adjusting the amplifier

Remove F2 from the power supply after short-circuiting the input and making sure the output is not connected to anything else. Then put a multimeter in the 1A DC region at the ends of the fuse block, and with the (+) in its side with C2.

Turn the potentiometer to its end in a direction opposite to the clock. Check all connections and connect the power adapter to the network. The multimeter should point around 0A. If the reading is greater then an error must be present and you must immediately stop the power supply. In good condition the current should be about 100mA which with P1 must be set to 80mA. This means that the resting current in the power transistors will be about 50mA.

This is the whole process of adjusting the amplifier. We replace F2 fuse, after first shutting down the power supply. If an error has occurred, we can easily correct it by comparing the voltages at different points in the circuit. These voltages have been measured with the speaker connected and the input disconnected.

List of amplifier components

Resistors:

R1 = 120k | R2,R5,R6 = 3k3 | R3 = 120Ω | R4,R8 = 680Ω | R7 = 1k5 | R9 = 5k6 | Α10 = 1k2 | R11 = 2k7 | R12,R13 = 270Ω | R14,R15 = 15Ω | R16,R17 = 220Ω | R18,R19 = 1Ω/9W | R20 = 10Ω | R21,R22 = 1Ω | Ρ1 = 1k

Capacitors:

C1 = 470 pF | C2 = 10μF/63V | C3 = 150pF | C4 = 1000μ/4V | C5 = 220μ/40V | C6 = 47pF | C7,C8 = 560pF | C9 = 47nF | C10,C11 = 680nF | C12,C13 = 100nF

Semiconductors:

Τ1,Τ2 = BC556Α | Τ3,Τ5 = BC547B | Τ4 = BC639 | Τ6 = BC557B | Τ7 = BDX67B,BDX67C | Τ8 = BDX66B,BDX66C | D1 = 9V1/1.3W | D2,D3 = 1Ν4148,1Ν914,BAW62

Other:

2 heatsinks 1.2 ° C / W or 1.8 ° C / W (see text) | Insulators for power transistors (mica)

List of power supply components

Resistors:

R1, R2 = 3k3 / 1W

Capacitors:

C1 = 100nF | C2, C3 = 4700μF / 63V

Semiconductors:

D1, D2 = LED | B1 = B80C 3200/5000 Rectifier (Bridge)

Fusses:

F1 = 1.4A (approx.) | F2, F3 = 2.5A (approximately)

Other:

Toroidal transformer = Secondary 2 x 30V - 2x 3,75A | S1 = bipolar switch | Two fuses for PCB | A fuse box for 220V

Sourced by.Next.gr

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Power 2h-30-Vatt 12 volts, working scheme

Not expensive, High-quality sound, Small parts and easy to assemble, Do not need to be tuned.Today can offer to your attention an amplifier that I have gathered from (almost) stuff I have lying in store. Long ago, working in the workshop, we often filmed amplifiers machines, since they come without tape recorders ​​and to put an ordinary tape recorder had to dismantle the amplifiers are !!! I left a couple of times since amplifier chips such as the LA4708. Time has passed since then a lot until my sister had not asked to do anything for his laptop to play in the yard with an acceptable quality and loud sound as speakers 2 pcs idle at home!

Power 2h-30-Vatt 12 volts, working scheme

It is taken from the datasheet half and half just from the people and schemes are proven over the years !!! If you look at the diagram, the capacitors C3 and C4 - a savings standing on the output of the amplifier, without a way (as if the sound disappears at high bass and not enough to drive the speakers). The amplifier where I desoldering the chip standing at the entrance storage choke (but I was too lazy to shake it, because it was a little too big standard, and the image at the top of his nebylo), it was decided to do without it !!! Increased denomination was in microfarads and capacitor C7 to 3300 microfarads, put dop.kondensatory input to the sound source and of the zener instead I put krenochku 5V to 5 foot (because it was under the hand) Well, all of the components that we need:

Sorry I forgot to add a couple of SMD capacitors there, standing at the entrance, but roughly the size of clear =) I must say that the capacitors C1, C2, C5, C6 (Mylar or polypropylene). Next Ludim, drills, soldered components from small to large. Unfortunately I lost zaglyuchila feshka and photos with my tinning and soldering = (There was only the result of the test and for 2 weeks =)

Put it on the active cooling, in Signet will be provided !!! My advice is not to actively, but rather to increase the area of the radiator. The following seals:

Power gives its net 20-30 watt channel! Tested on AS35! Keep in mind that this , no volume controls are not present !!! Before starting up the volume to a minimum !!! Starts amplifier from normal BP computer, it still works as well (there is no time to stick his body =)

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Simple Low-Power Audio Amplifier

The small-signal amplifier is generally referred to as a voltage amplifier because it usually converts a small input voltage into a much larger output voltage. The audio power amplifier works on the basic principle of converting low-power audio signal to a suitable level to be delivered to the load.

This low-power amplifier circuit is useful for the amplification of sound from small-signal devices such as mobile phones, laptops or desktops.

Circuit and working
As shown in Fig. 1, this circuit is built around a step-down transformer (X1), bridge rectifier BR1, regulators 7809 (IC1) and 7909 (IC2), dual op-amp TL072 (IC3), low-power amplifier LM386 (IC4) and some other components.

The circuit can be divided into two sections—dual power supply section and amplifier section. The dual power supply section is built around step-down transformer X1 (230V ac primary to 12V-0-12V, 1A secondary) and two voltage regulators 7809 and 7909. IC 7809 is a positive voltage regulator, while 7909 is a negative voltage regulator. Diodes D1 and D2 are used to protect IC1 and IC2 against reverse voltages from capacitors connected to the regulators. These regulators provide ±9V regulated output for the operation of the circuit.

Use suitable heat sinks with the regulator ICs because they get hot during operation. In case of overheating, there is provision for a thermal shutdown.

The amplifier section is built around TL072 (IC3) and a low-power amplifier LM386. The op-amp A1 of IC3 operates as a low-noise preamplifier. Capacitor C8 is used in order to pass low frequency. The op-amp A2 of IC3 operates as a low-pass filter. For changing the cut-off frequency, you have to change the values of capacitors C11 and C12.

 Simple Low-Power Audio Amplifier circuit Diagram

LM386 is a low-power amplifier IC with built-in biasing and inputs that are referred to the ground. It has a gain of 20 and can drive a speaker of 8-ohm impedance.

The circuit is simple to use. You have to simply feed the output from a mobile phone, or any other low-volume device, into RCA1 socket on the PCB. The amplified sound can be listened-to through the speaker (LS1). Potentiometer VR1 is used for volume control.
 
Construction and testing
An actual-size, single-side PCB for the simple low-power amplifier is shown in Fig. 2. Its component layout is shown in Fig. 3. After assembling the circuit on the PCB, enclose it in a suitable plastic box.

Fix RCA1 socket on the front side of the box for an audio-in signal. Fix a three-pin connector on the PCB for connecting secondary terminals (12V-0-12V) of transformer X1 and to two-pin connector on the rear side for mains 230V AC, 50Hz. Fix the transformer firmly on the cabinet with screws or nuts and bolts. Connect the speaker affixed on top of the box or placed at a distance. Use a shielded cable for connecting to the RCA socket.


Before inserting IC3 and IC4 into their respective IC bases, verify that all the connections have been made properly.

Sourced By : EFY  Author :  S.C. Dwivedi

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Simple Headphone Amplifier Circuit Diagram

This is the Simple Headphone Amplifier Circuit Diagram. You can use any NPN transistor. You can drive this circuit with a 9V batery. .

Simple Headphone Amplifier Circuit Diagram

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Build 20W MOSFET Power Amplifier Circuit with IFR9520,IFR520

As we are like to show you about audio and sound circuit ,I found the circuit which is good one for power amplifier with one MOSFET.

The output power of an operational amplifier is often increased by a complementary emiter follower.

It can also be done with a MOSFET,but it is not a good idea to connect such a device as a complementary souce follower because the maximum output voltage of the opamp is then reduced appreciably by the gate-source control voltage of the MOSFET ,which can be a couple of volts.

20W MOSFET Power Amplifier Circuit with IFR9520,IFR520

20W power amp MOSFET

Another approach is to connect two MOSFETs as a complementary drain follower.The (alternating) output current provided by the MOSFETs is limited by the level of the supply voltages and the saturateion voltages of T3 and T4 Resistor R8,together with R9,provides feedback for both the opamp and MOSFETs .

The open-loop amplification of the opampis,therefore,increased by (1+R8/R9).the closed-loop amplification of the complete amplifier is (1+R3/R2).

The current source formed by T1 and T2 is required for arreanging the quiescent current of T3 and T4 at 50 mA.The values of resistors R4 and R5 are such that,without the current source the voltage drop across the resistor resulting from the direct current through the opamp is not sufficient to switch on T3 and T4 .with the current source,and depending on the setting of P1,the voltages across R4 and R5 rise,which increases the quiescent current through T3 and T4.

In view of the temperature dependence of the quiescent current,T2 must be mounted on the common heat sink(c. 5 K/W) of the MOSFETs.

The output power is not less than 20 W into 8 ohm,at which level the harmonic distortion amounts to 0.075 per cent at 100 Hz to 0,135 per cent at 10 kHz.[link]

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100 Watt Power Amplifier Circuit With IC TDA7294

Power Amplifier TDA7294 is a power amplifier with IC Power Amplifier is a mono 100W Class AB operation of OCL.

The power supply circuit. Positive, negative, and ground. Usually, we use the power supply circuit to + /-25V to + /-35V at 100W RMS will be used to heat sufficiently.

After many members have already made the TDA7294 as I know, with a sound quality that is the very gods or Hi-End itself.


100 Watt Power Amplifier Circuit With IC TDA7294

Several days before the member’s PM to me saying that I had an amplifier using IC TDA7294 to have more of the same. Higher power. And low heat.

Achieved by increasing the voltage raising circuit For the more, it means high power and high heat up. Today I have come across. I use IC TDA7294 circuit at the time.

In-Home Use amplifier circuit is a Class G amplifier with low power consumption, resulting in the loss of a 20V DC power less.

And when you’re driving a high-power random access is party to a rhythm. Principles to do it. I took out a membership you can do is try to build up a bit.[link]

We provides PCB both top and bottom side for you.

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TDA1562Q 54 W Amplifier Circuit Diagram

This is the simple Using TDA1562Q 54 W Amplifier Circuit Diagram. The integrated output amplifier described in this article consists of little more than one integrated circuit. It is intended especially for use in motor vehicles and other battery operated applications. Although it appears simple and hardly worth looking at, the amplifier can produce an appreciable audio power output.[link]

Using TDA1562Q 54 W Amplifier Circuit Diagram

Data

PropertiesHigh power output through Class-H operation

Low power dissipation during reproduction of music signals

Proof against short-circuits

Protection against excessive temperatures

Standby switch

No power-on or power-off clicks

Visible error indication

Measurement results (at Ub=14.4 V)

Supply voltage 8–18 V

Sensitivity 760 mV r.m.s.

Input impedance 70 kΩ

Power output 54 W r.m.s.

into 4 Ω (f=1 kHz; THD+N=1%)

Harmonic distortion (THD+N) at 1 W into 4 Ω: 0.046% (1 kHz)

0.29% (20 kHz)

at 35 W into 4 Ω: 0.12% (1 kHz)

0.7% (20 kHz)

Signal-to-noise ratio (with 1 W into 4 Ω) 88 dBA

Power bandwidth 7.5 Hz – 185 kHz (at 25 W into 4 Ω)

Quiescent current about 135 mA (‘on’)

COMPONENTS LIST

Resistors:

R1 = 1MΩ

R2 = 4kΩ7

R3 = 1kΩ

R4 = 100kΩ

Capacitors:

C1,C2 = 470nF

C3,C4 = 10μF 63V radial

C5,C6,C8 = 4700μF 25V radial

(18mm max. dia., raster 7.5 mm)

C7 = 100nF, raster 5 mm

Semiconductors:

D1 = high-efficiency-LED

IC1 = TDA1562Q (Philips)

Miscellaneous:

S1 = single-pole on/off switch

Four spade connectors, PCB mount

Heatsink for IC1 (Rth<2.5>

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TDA 2050 - LM 1875 Power Amplifier Cirrcuit Diagram

This is the IC based TDA 2050 - LM 1875 Audio Power Amplifier Cirrcuit Diagram. This is not an usual circuit, but an attempt to make a PCB that is suitable for TDA2050 and LM1875 and has all the necessary circuitry on board - power supply, speaker protection, delayed turn-on and fast turn-off. This is achieved using the convenient uPC1237 IC.

TDA2050 and LM1875 are pin to pin compatible, the differences in their schematics are the values of a couple resistors and one capacitor. All this allows to make an universal circuit board, suitable for any of these two ICs.It is 2x30W, but it depend of the power supply voltage and the impedance of the speakers connected to the output.

TDA 2050 - LM 1875 Power Amplifier Cirrcuit Diagram

PCB top layer

PCB bottom layer

Parts List

B1 KBU8M FBU4
C1 100nF C050-024X044
C2 100nF C050-024X044
C3 1000uF E5-10,5
C4 1000uF E5-10,5
C6 2.2uF C050-075X075
C7 220nF C050-030X075
C8 22uF E3,5-8
C9 100nF C050-024X044
C10 100nF C050-024X044
C11 1000uF E5-10,5
C12 1000uF E5-10,5
C13 4.7uF E2,5-6
C14 2.2uF C050-075X075
C15 220nF C050-030X075
C16 22uF E3,5-8
C17 4700uF E7,5-18
C18 4700uF E7,5-18
C19 47uF E2,5-7
C20 22uF E3,5-8
C21 22nF C050-025X075
D5 1N4148 DO35-7
D6 1N4004 DO41-10
D7 BZX85C12V DO41Z10
H1 MOUNT-PAD-ROUND3.0 3,0-PAD
IC1 LM1875 T05D
IC2 LM1875 T05D
IC3 UPC1237 SOP8
IN 6410-02
IN1 6410-02
J1 OUT1 AC2
J2 OUT2 AC2
J3 AC AC3
JP1 JP1
K1 G2R2 G2R2
LED 6410-02
LED2 LED5MM
LED3 6410-02
R1 1k 0207/2V
R2 20k 0207/12
R3 22k 0207/7
R4 1M 0207/7
R5 1R 0414V
R6 1k 0207/2V
R7 20k 0207/12
R8 22k 0207/7
R9 1M 0207/7
R10 1R 0414V
R11 2k2 0207/7
R12 120k 0207/7
R13 120k 0207/10
R14 56k 0207/7
R15 9k1 0207/7
R16 10k 0207/7
R17 92k 0207/10
R18 330R 0207/10
R19 68k 0207/7
R20 3k9 0207/10
R21 10k 0207/7
T2 MPSA42 TO92-EBC

Author: Hristo - xristostyahoo.com Sourced By: Circuitsproject

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Digital ICs Drive Amplifier Circuit Diagram

This is the Digital ICs Drive Amplifier Circuit Diagram . Digital ICs and opto-isolators provide the drive for this TMOS servo amplifier, resulting in fewer analog circuits and less drift. Fast and consistent turn-on and turn-off characteristics also enable accurate analog output results directly from the digital signal without the need for analog feedback.

 Digital ICs Drive Amplifier Circuit Diagram

An `H` bridge configuration is employed for the servo amplifier, which obtains complementary PWM inputs from digital control circuits. The PWM inputs are applied via opto-isolators, which keep the digital control logic isolated from the 75 V supply used for the amplifier.

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Op-Amp Dc Offset Shift Circuit Diagram

This is the simple Op-Amp Dc Offset Shift Circuit Diagram. The dc values of op-amp offsets can`t always be taken for granted when delivering ac outputs. No device is ever exactly symmetrical for maximum positive slew rate versus maximum negative slew rate. Consequently, there is always some range of output slew rates in which the device used limits in one direction more severely than in the other. 

Op-Amp Dc Offset Shift Circuit Diagram

What results in rectification of the ac signal and an apparent shift of the dc offset. This test circuit can check for the shift phenomenon. The accompanying table and graph illustrate the results obtained for four devices, all of different types.As frequency and slew rate are increased, the effect can be either relatively abrupt (LF412CN and NE55532N) or relatively gradual (LF358J and TL0820P).

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Audio Power Amplifier Circuit Diagram

This is the ic based Audio Power Amplifier Circuit Diagram. The LM383 is an audio-power amplifier that is capable of producing up to 8 W of audio output. R1 is essentially a load resistor for the hand-held transceiver`s audio output. R2 can be composed of two fixed resistors in a 10:1 divider arrangement, but using a potentiometer makes it easy to set the amplifier`s maximum gain. 

 Audio Power Amplifier Circuit Diagram

When powered from a vehicle`s electrical system, the amplifier`s +12V power source requires filter L1 to eliminate alternator whine. The LM383 can ·be mounted directly on the heatsink because the mounting tab is at ground potential.

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5 Watt Class-A Audio Amplifier Circuit diagram

This solid-state push-pull single-ended Class A circuit is capable of providing a sound comparable to those valve amplifiers, delivering more output power (6.9W measured across a 8 Ohm loudspeaker cabinet load), less THD, higher input sensitivity and better linearity. Voltage and current required for this circuit are 24V and 700mA respectively, compared to 250V HT rail and 1A @ 6.3V filament heating for valve-operated amplifiers. The only penalty for the transistor operated circuit is the necessity of using a rather large Heatsink for Q2 and Q3 (compared to the maximum power delivered).In any case, the amount of heat generated by this circuit can be comparable to that of a one-valve amplifier. An optional bass-boost facility can be added, by means of R5 and C5.

5 Watt Class-A Audio Amplifier Circuit diagram

Parts:

P1 = 47K
R1 = 100K
R2 = 12K
R3 = 47K
R4 = 8.2K
R5 = 1.5K
R6 = 2.7K
R7 = 100R
R8 = 100R
R9 = 560R-1/2W
R10 = 1R-1/2W
Q1 = BC560
Q2 = BD439
Q3 = BD439
C1 = 10uF-63V
C2 = 10uF-63V
C3 = 47uF-25V
C4 = 100uF-35V
C5 = 150nF-63V
C6 = 220uF-25V
C7 = 220uF-25V
C8 = 1000uF-25V
SPKR = 5W-8R Speaker

Notes:

• If necessary, R2 can be adjusted to obtain 13V across C8 positive lead and negative ground.
• Total current drawing of the circuit, best measured by inserting the probes of an Avo-meter across the positive output of the power supply and the positive rail input of the amplifier, must be 700mA. Adjust R8 to obtain this value if necessary.
• Q2 and Q3 must be mounted on a finned Heatsink of 120x50x25mm. Minimum dimensions.
• Add R5 and C5 if the bass-boost facility is required.

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Reliable 6 Watt Hi Fi Audio Amplifier Using TDA2613

A 6 watt audio amplifier circuit using TDA2613 is shown here. TDA2613 is an integrated Hi-Fi  audio amplifier IC from Philips Semiconductors. The IC is switch ON / switch OFF click proof, short circuit proof, thermally protected and is available in 9 pin single in line plastic package. In the given circuit, TDA2613 is wired to operate from a single supply.

Capacitor C4 is the input DC decoupler while capacitors C5, C6 are power supply filters. Input audio is fed to the non inverting input through capacitor C4. Inverting input and Vp/2 pins of the IC are tied together and connected to ground through capacitor C3. Capacitor C2 couples the speaker to the ICs output and the network comprising of capacitor C1 and resistor R1 improves the high frequency stability.
.
Reliable 6 Watt Hi Fi Audio Amplifier Circuit diagram

Notes.

• Assemble the circuit on good quality PCB.
• Supply voltage (Vs) can be anything between 15 to 24V DC.
• Heat sink is necessary for TDA2613.
• Do not give more than 24V to TDA2613.

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20 Watt Power Amplifier

This IC chip was designed specifically for use in power boosting applications in automobiles. It is self protecting against short circuits and thermal problems. In the bridge configuration shown it will deliver 20 watts of power into a 2 ohm speaker operating at 14.4 volts.

20 Watt Power Amplifier Circuit Diagram

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Sooper Amplifier Using BEL1895 I.C

Here is a very simple and easy to use audio amplifier using I.C BEL(Bharat electronics limited)1895 , a very common IC. This circuit can run on 3V to 6v , making it easy to use in pocket amplifier. Cost is under 25/-

Parts list:

BEL1895 I.C (DIP8),
C1 = 470uF/10V,
C2 = 1000uF/16V,
C3 = 220uF/10V,
C4 = 100uF/10V,
C5 = 4.7uF/10V,
C6 = 47pF,
C7,C8 = 1uF,
R1 = 47Ohm,
R2 = 470Ohm,
R3 = 100K,
R4 = 1Ohm,
R5 = 10K V/C,
speaker, etc…
Total cost is around 20-30 rupeess(INR) or 0.6USD. 

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10W Small Audio Amplifier

This is a simple 10W Small Audio Amplifier circuit diagram. You can use this powerful amplifier in any small audio project. It is very small (6.5 x 4.5 cm).It outputs 10W and uses a 9V battery.

10W Small Audio Amplifier

Component

 

PCB

Components List

R1 : 6 Ohm

R2 : 220 Ohm

R3 : nothing

R4 : 10 KOhm pontesiometer

C1 : 2200 uF / 25V

C2 : 470 uF / 16V

C3 : 470 nF / 63V

C4 : 100 nF

C5 : nothing

C6 : nothing

IC1 : TDA 2003

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Single -IC Dual-tones Siren Circuits Diagram

Double-tone Police sound Circuits Diagram

This circuit is intended for children fun, and can be installed on bicycles, battery powered cars and motorcycles, but also on models and various games and toys. With SW1 positioned as shown in the circuit diagram, the typical dual-tone sound of Police or Fire-brigade cars is generated, by the oscillation of IC1A and IC1B gates. With SW1 set to the other position, the old siren sound increasing in frequency and then slowly decreasing is reproduced, by pushing on P1 that starts oscillation in IC1C and IC1D. 

The loudspeaker, driven by Q1, should be of reasonable dimensions and well encased, in order to obtain a more realistic and louder output. Tone and period of the sound oscillations can be varied by changing the values of C1, C2, C5, C6 and/or associated resistors. No power switch is required: leave SW1 in the low position (old-type siren) and the circuit consumption will be negligible.

Single -IC Dual-tones Siren Circuits Diagram

Parts:

R1,R3___470K   1/4W Resistors

R2______680K   1/4W Resistor

R4_______82K   1/4W Resistor

R5______330K   1/4W Resistor

R6_______10K   1/4W Resistor

R7_______33K   1/4W Resistor

R8________3M3  1/4W Resistor

C1,C5_____10µF  25V Electrolytic Capacitors

C2,C6_____10nF  63V Polyester Capacitors

C3_______100nF  63V Polyester Capacitor

C4_______100µF  25V Electrolytic Capacitor

D1-D3___1N4148  75V 150mA Diodes

IC1_____4093   Quad 2 input Schmitt NAND Gate IC

Q1______BC337   45V 800mA NPN Transistor

P1______SPST Pushbutton

SW1_____DPDT Switch

SPKR____8 Ohm Loudspeaker

B1______6V Battery (4 AA 1.5V Cells in series)

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25 Watt Audio Amplifier Circuits Diagram

25 Watt Audio Amplifier Circuits Diagram

Parts:

R1,R4_________47K  1/4W Resistors

R2____________4K7  1/4W Resistor

R3____________1K5  1/4W Resistor

R5__________390R   1/4W Resistor

R6__________470R   1/4W Resistor

R7___________33K   1/4W Resistor

R8__________150K   1/4W Resistor

R9___________15K   1/4W Resistor

R10__________27R   1/4W Resistor

R11_________500R   1/2W Trimmer Cermet

R12,R13,R16__10R   1/4W Resistors

R14,R15_____220R   1/4W Resistors

R17___________8R2    2W Resistor

R18____________R22   4W Resistor (wirewound)

C1___________470nF  63V Polyester Capacitor

C2___________330pF  63V Polystyrene Capacitor

C3,C5________470µF  63V Electrolytic Capacitors

C4,C6,C8,C11_100nF  63V Polyester Capacitors

C7___________100µF  25V Electrolytic Capacitor

C9____________10pF  63V Polystyrene Capacitor

C10____________1µF  63V Polyester Capacitor

Q1-Q5______BC560C   45V 100mA Low noise High gain PNP Transistors

Q6_________BD140    80V 1.5A PNP Transistor

Q7_________BD139    80V 1.5A NPN Transistor

Q8_________IRF530  100V 14A N-Channel Hexfet Transistor

Q9_________IRF9530 100V 12A P-Channel Hexfet Transistor

Power supply circuit diagram

Parts:

R1____________3K3  1/2W Resistor C1___________10nF 1000V Polyester CapacitorC2,C3______4700µF   50V Electrolytic CapacitorsC4,C5_______100nF   63V Polyester Capacitors D1__________200V 8A Diode bridgeD2__________5mm. Red LED F1,F2_______3.15A Fuses with sockets T1__________220V Primary, 25 + 25V Secondary 120VA Mains transformer PL1_________Male Mains plug SW1_________SPST Mains switch

Notes:

• Can be directly connected to CD players, tuners and tape recorders. Simply add a 10K Log potentiometer (dual gang for stereo) and a switch to cope with the various sources you need.
• Q6 & Q7 must have a small U-shaped heatsink.
• Q8 & Q9 must be mounted on heatsink.
• Adjust R11 to set quiescent current at 100mA (best measured with an Avo-meter connected in series to Q8 Drain) with no input signal.
• A correct grounding is very important to eliminate hum and ground loops. Connect to the same point the ground sides of R1, R4, R9, C3 to C8. Connect C11 to output ground. Then connect separately the input and output grounds to power supply ground.
• An earlier prototype of this amplifier was recently inspected and tested again after 15 years of use.

Technical data:

Output power:

well in excess of 25 Watt RMS @ 8 Ohm (1KHz sine wave)

Sensitivity:

200mV input for 25W output

Frequency response:

30Hz to 20KHz-1dB

Total harmonic distortion @ 1KHz:

0.1W 0.014% 1W 0.006% 10W 0.006% 20W0.007% 25W 0.01%

Total harmonic distortion @10KHz:

0.1W 0.024% 1W 0.016% 10W 0.02% 20W0.045% 25W 0.07%

Unconditionally stable on capacitive loads

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10W Stereo Audio Amplifier Using TDA2009A

This is a schematic of a 10W stereo audio amplifier using TDA2009A amplifier IC. TDA2009A is a good IC provides quality sound. It has built in features like output current protection and thermal protection etc. The circuit can be operate between 8 to 24V DC with 1 to 2 amphere.

10W Stereo Audio Amplifier Circuit Diagram :

If you want to operate this 10 watt amplifier circuit with watt amplifier circuit with mains supply then use a filtered and stable power supply to reduce mains hum. 10 watt out put power can be obtained by providing 20V 1.5A to the circuit. Use good and thick heatsink with the IC. 

Source By : Circuitsstream

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Simple Telephone Amplifier Circuit Diagram

The output telephone signal is more powerful then the signal fed to base of the transistor T₁. The output signal from transistor T₁ is fed to pin no 3 of power amplifier LM386 which amplify up to necessity level and output is obtained from pin no 5 is fed to speaker through capacitor C₉. The V_CC is given to IC₁ through pin 6. The telephone signal is fed in to circuit through two ways.

1. Direct supply telephone signal from telephone line to the point where coil L₁ is connected as shown in figure 2.
2. Or connect this peak up coil L₁ and so adjusted near telephone set where excellent voice be able to single out. 

Simple Telephone Amplifier Circuit Diagram

PARTS LIST

Resistors (all ¼-watt, ± 5% Carbon)

R₁ = 100 KΩ

R₂ = 39 KΩ

R₃ = 2.2 KΩ

R₄ = 680 Ω

R₅ = 100 Ω

VR₁ = 4.7 KΩ

VR₂ = 10 KΩ

Capacitors

C₁ = 27 KPF (273)

C₂, C₄ = 2.2 µF/16 V

C₃ = 22 µF/16 V

C₅, C₁₀ = 100 µF/16 V

C₆ = 10 µF/16 V

C₇ = 100 KPF (104)

C₈ = 47 KPF (473)

C₉ = 220 µF/16 V

Semiconductors

T₁ = BC147B

IC₁ = LM386 power amplifier

Miscellaneous

L₁ = Pick up Coil

Speaker 8Ω

SW₁ = On/Off switch

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