100W Amplifier with Transistor 2N3055 and MJ2955

This is the circuit diagram of 100W amplifier with paired transistor 2N3055 and MJ2955. 2N3055 and MJ2955 is a silicon power transistor used mostly in amplifier and power supply circuitsbut it  is designed for general–purpose switching and amplifier applications. 2N3055 transistor is packed in a TO-3 can, the maximum power rating is 115W, voltage 60V and 15 amperes maximum with a beta gain of 20 to 70 at a collector current of 4A.

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Mini Audio Amplifier with Transistors

This is the mini audio amplifier which built using inexpensive transistors. The circuit is quite simple, low-cost and it consumes very low energy to work. It will work with 3V battery / power supply circuit

How the Circuit Operates:

The output is push-pull and needs lower than 3mA (without any signal) but drives the earpiece to a very loud level when audio is detected. The entire circuit is DC coupled and this makes it really challenging to set up.

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30W Audio Power Amplifier

Here the 30W audio amplifier circuit for you who need a low power amplifier, but has good audio output quality and made from distinct components. The circuit design does not have any innovation. In the power stage is a Darlington pair of transistors packed TOP3, which can be screwed onto a heatsink, adding between them and the heatsink suitable leaves mica and ointment silicone for better dissipation of temperature.

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50W Audio Power Amplifier based ICL8063

This is the 50W audio power amplifier for general purpose application. The circuit is based ICL8063 and 2N3055/2N3791 power transistor . The amplifier has an input for a radio, TV, stereo or other line level devices. It also has a phono input for a record player, guitar, microphone or other un-amplified source. With the addition of a low pass filter at the input, it makes a great amplifier for a small subwoofer.

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60W Class-A Power Amplifier Circuit

The circuit shows that each sub-amplifier consists of two stages of voltage gain. The first stage consists of two complementary stages in common emitter connection [Q1-7], whose profit is x2.3. The second stage is a current mirror stage [Q13-14] has load resistor that goes to 0V. The gain of this stage is x200. Consequently, the overall open-loop voltage gain is about x460 and so, since the closed loop gain is x26.7, the reduction due to negative feedback is x17.2 or 24db.

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200W Leach Amplifier Circuit

Leach Amplifier is an well known amplifier circuit originally introduced by Marshall Leach. In this project, the amplifier design is the modified one. The circuit is based on transistors for the final amplification, yes it many power amplifier used just for single output. But you'll find the great quality of this amplifier. The amplifier will deliver the power audio output up to 200W. You may build two similar circuit for stereo input/output amplifier.

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50W Power Amplifier Circuit

50W power amplifier circuit diagram using TIP33C and TIP34C power transistor. This easy power audio amplifier was originally developed for a circuit board workshop, conducted by the OSU IEEE Student Group. In the workshop, there are 20 participants and every participant constructed this amplifier, by etching and drilling the single sided circuit board, soldering all components, and attaching a pre-built heatsink assembly to the output transistors. Three workshops had been held in between 1995 to 1996. Although the schematic diagram is simple, this power amplifier have impressive audio performance, having a frequency response to approx 40 kHz, pretty low noise, reasonably fast slew rate, and approx 50 watts (real "RMS" power) using the appropriate +/- 40 volt unregulated power supply.

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200W Power Amplifier Circuit

This is the circuit diagram of 200W power amplifier with high quality audio output. This is a bridge amplifier based power IC TDA2030 and power transistor BD708/BD708 KT818/KT819.

Schematic diagram:

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2000W Power Amplifier Circuit

This is the schematic diagram of 2000W power amplifier circuit. The diagram is quite hard to built, you may use electronic design diagram software to help you to design the PCB.

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2W Audio Amplifier Circuit based TIP31A/TIP32A

Here the 2W audio amplifier circuit which built based a couple of power transistor TIP31A and TIP32A. This is a mono transistored amplifier, built the similar circuit for stereo audio amplifier.

Components list:

R1,R2 = 33K 1/4W R3 = 33R 1/4W R4 = 15K 1/4W R5,R6 = 1K 1/4W R7 = 680R 1/4W R8 = 120R 1/2W R9 = 100R 1/2W Trimpot P1 = 10K Linear Potentiometer D1 = 1N4148 SPKR = 3-5 Watt / 8, 4 or 2 Ohm

C1,C2 = 10µF/63V C3 = 100µF/25V C4,C7 = 470µF/25V C5 = 47pF C6 = 220nF C8 = 1000µF/25V Q1 = BC560C Q2 = BC337 Q3 = TIP31A Q4 = TIP32A

2W Audio Amplifier Circuit based TIP31A/TIP32A source: http://www.redcircuits.com/Page33.htm

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5W Audio Amplifier circuit based BD439

This audio amplifier circuit built based power transistor BD439, capable to deliver up to 5W audio output.

Components List:
P1 = 47K Log. Potentiometer
R1 = 100K - 1/4W
R2 = 12K - 1/4W
R3 = 47K - 1/4W
R4 = 8K2 - 1/4W
R5 = 1K5 - 1/4W
R6 = 2K7 - 1/4W
R7,R9 = 100R - 1/4W
R8 = 560R - 1/2W
R10 = 1R - 1/2W
C1,C2 = 10µF/63V
C3 = 47µF/25V
C4 = 100µF/35V
C5 = 150nF
C6,C7 = 220µF/25V
C8 = 1000µF/25V
Q1 = BC560C
Q2,Q3 = BD439

Circuit Notes:
If needed, R2 could be modified to get 13V across C8 positive lead and negative ground.
Q2 and Q3 should be mounted on a finned heatsink of 120x50x25mm. minimum dimensions.
Total electric current drawing of the circuit, recommended measured by inserting the probes of an multimeter across the positive output with the power supply and the positive rail input of the amplifier, should be 700mA. Adjust R8 to acquire this value if needed.
Add R5 and C5 if the bass-boost facility is needed.

5W Audio Amplifier circuit based BD439 Source

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10W Audio Amplifier using TIP41A/TIP42A

Here the 10W audio amplifier circuit based NE5532 and a couple of power transistor TIP41A/TIP42A

Component Parts:

P1 22K Log.Potentiometer P2 100K Log.Potentiometer R1 820R R2,R4,R8 4K7 R3 500R Trimpot R5 82K R6,R7 47K R9 10R R10 R22 4W Resistor (wirewound) D1 1N4148 IC1 NE5532

C1,C8 470nF 63V C2,C5 100uF 25V C3,C4 470uF 25V C6 47pF 63V C7 10nF 63V C9 100nF 63V Q1 BC547B NPN Transistor Q2 BC557B PNP Transistor Q3 TIP42A PNP Transistor Q4 TIP41A NPN Transistor J1 RCA audio input socket

This circuit is similar to the 18 Watt Audio Amplifier, and was intended mainly to satisfy the requests of correspondents unable to locate the TLE2141C chip. It works with the widespread NE5532 Dual IC but, obviously, its potential output will likely be comprised from the 9.5 - 11.5W range, since the voltage source rails can not exceed ±18V.

As amplifiers of this sort are commonly applied to drive small to medium sized loudspeaker cabinets, the bass frequency range is rather sacrificed. Therefore a bass-boost manage was inserted inside the feedback loop with the amplifier, so as to overcome this dilemma without having high quality losses. The bass lift curve can reach a maximum of +16.4dB @ 50Hz. In any situation, even when the bass control is rotated completely counterclockwise, the amplifier frequency response exhibits a gentle raising curve: +0.8dB @ 400Hz, +4.7dB @ 100Hz and +6dB @ 50Hz (referred to 1KHz).

10W Audio Amplifier Circuit Notes:

• The input can be immediately connected to CD players, tuners and tape recorders.
• Schematic exhibits left channel only, but C3, C4, IC1 as well as the power supply are typical to each channels.
• A log type for P2 will guarantee a far more linear regulation of bass-boost.
• Tend not to exceed 18 + 18V supply.
• Numbers in parentheses show IC1 proper channel pin connections.
• Q3 and Q4 has to be mounted on heatsink.
• D1 has to be in thermal contact with Q1.
• Set the volume manage for the minimum and R3 to its minimum resistance.
• Quiescent current (preferred measured with an multimeter in series with Q3 Emitter) is not crucial.
• Power-on the circuit and adjust R3 to read a electric current drawing of about 20 to 25mA.
• Wait about 15 minutes, keep an eye on if the electric current is varying and readjust if required.
• A right grounding is extremely necessary to remove hum and ground loops. Connect for the identical point the ground sides of J1, P1, C2, C3 &C4. Connect C9 to the output ground.
• Then connect separately the input and output grounds for the power source ground.

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18W Audio Amplifier Circuit

The following diagram is mono 18W audio amplifier circuit. This transistored amplifier is powered by a couple of power transistor TIP41A and TIP42A. Build two similar circuit for stereo amplifier.

Amplifier Parts List:
P1 = 22K Log. Potentiometer (Dual-gang for stereo)
R1 = 1K 1/4W
R2 = 4K7 1/4W
R3 = 100R 1/4W
R4 = 4K7 1/4W
R5 = 82K 1/4W
R6 = 10R 1/2W
R7 = R22 4W Resistor (wirewound)
R8 = 1K 1/2W Trimmer Cermet (optional)
C1 = 470nF/63V Polyester Capacitor
C2,C5 = 100µF/3V Tantalum bead Capacitors
C3,C4 = 470µF/25V Electrolytic Capacitors
C6 = 100nF/63V Polyester Capacitor
D1 = 1N4148
IC1 = TLE2141C
Q1 = BC182
Q2 = BC212
Q3 = TIP42A
Q4 = TIP41A
J1 = RCA audio input socket

Power Supply Parts List:
R9 = 2K2 1/4W
C7,C8 = 4700µF 25V Electrolytic Capacitors
D2 = 100V 4A Diode bridge
D3 = 5mm. Red LED
T1 = 220V Primary, 15 + 15V Secondary, 3A
PL1 = Male Mains plug
SW1 = SPST Mains switch

Circuit Notes:

• The power supply do not exceed 23 + 23V supply, 15V transformer output is the recommended.
• Q3 and Q4 must use heatsink to prevent overheating.
• D1 must be in thermal contact with Q1.
• Adjust R3 to read a current between 20 to 30 mA with no input signal.
• To facilitate quiescent current setting add R8 (optional).
• A correct grounding is very important to eliminate hum and ground loops. Connect to the same point the ground sides of J1, P1, C2, C3 & C4. Connect C6 to the output ground.
• Then connect separately the input and output grounds to the power supply ground.

18W Audio Amplifier Circuit source: http://www.redcircuits.com/Page1.htm

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600W Power Amplifier Circuit

This high fidelity audio power amplifier circuit is built based the power IC of LM4702 from NATIONAL semiconductors and power transisfor of MJ11029/MJ11028 from ONSEMI (ON semiconductors). The circuit is designed for demanding consumer and pro-audio applications. You can also use this circuit with AV receivers, Audiophile power amps, Pro Audio High voltage industrial applications etc Amplifier output power maybe scaled by changing the supply voltage and number of output devices. The circuit includes thermal shutdown circuitry that activates when the die temperature exceeds 150. The circuit mute function, it will mutes the input drive signal and forces the amplifier output to a quiescent state when this function activated.

Technical Details:

• Maximum Output power @ 8ohms : 300watt
• Absolute max power supply voltage :38V to 40V
• Recommended power supply voltage :30V to 35V

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