This 200W MOSFET amplifier circuit designed for single or mono audio channel application. You should build two similar circuits for stereo audio application. Build one first for performance testing to ensure that this circuit really wongking well with great audio performance.

The power supply used for this circuit is a symmetrical / dual polarity type. You need 4 amperes minimum of transformer with +/- 45V output. For stereo application, use about 8 amperes, although the 5A transformer is good enough . You may use the power supply circuit design on this post: 200W Power Amplifier using Transistor

200W MOSFET Amplifier PCB Layout Design

Bottom / Chopper PCB Design

Top PCB Design / Component Placement

The main advantages of this solution are the following:
– High power with low voltage.
– Considerable power, even at high load values (Up to 16 Ohm).
With a load of 8 Ohms and a power supply voltage of ± 25V, the maximum performance that can be obtained is 150 W per channel. While with 16 Ohms load, and a power supply voltage of ± 35V, we will have a maximum of 170 W per channel.

This 300W RMS stereo power amplifier require symmetrical power supply to work, the circuit diagram is included in this post.

300W RMS Stereo Power Amplifier Schematic Design

300W RMS Stereo Power Amplifier Part List

SEMI-CONDUCTORS
4 TDA 7294

RESISTORS
56K Ohms (green, blue, orange) : 8
8K2 Ohms (gray, red, red) : 3
5K1  Ohms (green, brown, red) : 14
8.2 Ohms 1W (gray, red, gold) : 4
2.7 Ohms 1W (red, purple, gold) : 4
22K Ohms (red, red, orange) : 2
1K Ohms (brown, black, red) : 4

CAPACITORS
4700 uF / 35v electrolytic capacitor : 2
22 uF / 35v electrolytic capacitor : 12
1 uF / 35v electrolytic capacitor : 4
0.1 uF / 250v polyester capacitor : 4
0.1 uF / 100v polyester capacitor : 4
0.47 uF / 100v polyester capacitor : 4
10 pF / ceramic capacitor : 4
390 pF / ceramic capacitor: 2

MISCELLANEOUS
25-amp diode bridge : 1
Diodes 1N4148 : 2
fuse holders for printed and 6 amp fuse : 4
small 3-pin connectors : 2
large 3-pin connectors : 2
small 6-pin connector : 1
18x18v to 12 Amp transformer : 1
Square mica insulation. : 4
coils of 10 coils with air core : 4
Of 1/4 inch and wire 18.

The resistance of the 12v cooler is calculated:
(15 / milliamperes of fan) = x Ohms.

300W RMS Stereo Power Amplifier PCB Layout Design

Power Supply for 300W RMS Stereo Power Amplifier

Schematic Diagram 4in1: 100W RMS Power Amplifier With VU, Power Supply and Tone Control

Part Lists

Active Components

• IC TDA 7294 : 1
• IC 7812 : 1
• IC LM3914 : 1
• Diode Zener 12V : 2
• IC 4558 : 1
• Diode 1N4148 : 1
• Rectifier Bridge Diode 6 A : 1
• LED : 11

Resistors

• 390 Ω – 1/4w : 1
• 680 Ω – 1/4w : 1
• 1K Ohm – 1/4w : 2
• 2k2 Ohm – 1/4w : 3
• 2k7 Ohm – 1/4w : 1
• 3k3 Ohm – 1/4w : 1
• 5k6 Ohm – 1/4w : 1
• 8k2 Ohm – 1/4w : 1
• 10K Ohm – 1/4w : 4
• 20K Ohm – 1/4w : 2
• 22K Ohm – 1/4w : 3
• 30K Ohm – 1/4w : 1
• 47k Ohm – 1/4w : 1
• 10R ohm – 1/4w : 1
• 56R Ohm – 2w : 1
• 2K2 Ohm – 2w : 2
• Potensiometer 50K Ohm : 3

Capacitors

• 100pF nonpolar capacitor disc / ceramic : 2
• 6n8F nonpolar polyester capacitor : 2
• 10nF nonpolar polyester capacitor : 2
• 100nF nonpolar polyester capacitor : 6
• 220nF nonpolar polyester capacitor : 1
• 2.2uF/63V electrolytic capacitor : 1
• 10uF/63V electrolytic capacitor : 5
• 22uF/63v electrolytic capacitor : 2
• 100uF/63V electrolytic capacitor : 2
• 4700uF/63V electrolytic capacitor : 2

100W RMS Power Amplifier PCB Layout

Component Placement

This is a single channel (mono) audio system. For stereo audio system, you need two similar circuit and make some changes such as: use higher transformer current, higher diode current, higher capacitor value for the power supply module. Use only one power supply. Use stereo potensiometer and connect to the two boards using cable.

120W Power Amplifier Part List

Transistors

• 2N3055 (substitution: MJ15003 or 2N3772) : 2
• MJ2955 (substitution: MJ15004 or 2N3771) : 2
• TIP42 : 2
• TIP41 : 1
• 2SC2229 or 2SC2230 or C1573 : 2
• A1015 or A872 or A733 : 2

Capacitors

• 100uF/50V electrolytic capacitor: 2
• 470nF (474) nonpolar polyester capacitor: 1
• 100pF (101) nonpolar ceramic capacitor : 2
• 470pF (471) nonpolar ceramic capacitor : 2
• 10pF nonpolar ceramic capacitor : 2
• 100nF (104) 100V nonpolar polyester capacitor : 2

Resistors

• 0.33 Ω (5W) : 4
• 10 Ω to (1W) – brown, black, black : 1
• 100 Ω (1W) – brown, black, brown : 2
• 33 Ω (1/4W) – orange, orange, black : 1
• 150 Ω (1/4W) – brown, green, brown : 3
• 10KΩ (1/4W) - brown, black, orange : 1
• 1KΩ (1/4W) - brown, black, red : 1
• 4.7KΩ (1W) - yellow, violet, red : 1
• 68KΩ (1/4W) - blue, gray, orange : 1
• 56KΩ (1/4W) - green, blue, orange : 1
• 33KΩ (1/4W) – orange, orange, orange : 1
• 3.3KΩ (1/4W) – orange, orange, red : 2

Diodes

• 3A Diode 1N5404 : 2
• 1A Diode 1N4007 : 3
• Zener diodes between 20 and 24 volts : 1

Others

• 3A fuse
• small 3-pin (GP) connector
• large 6-pin connector (Molex)
• aluminum heatsink
• potentiometer of 20K if you want to add volume control

120W Power Amplifier PCB Layout Design

Bottom PCB Layout (Copper)

Top PCB Layout and Component Placement

How to mount the transistors to the aluminium heatsink, see below image:

The points are: prevent circuit shortage, use proper isolator and use thermal compound for maximum heat spreading to the heatsink. Use mica between the transistor and the heatsink.

Power Supply Circuit for 120W Power Amplifier

Power Supply Bottom PCB Layout

Power Supply Top PCB Design

Power Supply Part List

• Transformer for the mono amplifier should be 35 + 35 volts AC with a minimum of 3 amps. If the stereo channel, the amperage should be doubled.
• Capacitors of 4700 uF/63V: 4
• Diode bridge (rectifier) ​​of 15 Amps: 1

120W Power Amplifier Wiring Connection

This is how to connect the amplifier module to the speaker, power supply and audio input. And connect the power supply module to the transformer.

If you use it with only one 8 ohm speaker, it will deliver a power of 100w. The printed circuit board has the following measures: 13.6 cm x 13.9 single sided. The power supply used for this circuit is a symmetrical type which capable to delivers ± 50 VDC by 4 Amperes to the circuit. The power supply schematic is included in this board.

200W Amplifier PCB Circuit Board

200W Power Amplifier Parts

400W RMS Stereo Power Amplifier Part List

Transistors:

D1047 – 4 pieces
B817E – 4 pieces
A1015 – 6 pieces
TIP41C – 4 pieces
TIP42C – 4 pieces

Resistors:

6.8 ohms – 1W (blue, gray, gold) – 4 pieces
100 ohms – 1W (brown, black, brown) – 4 pieces
18K – 1 / 2W (brown, gray, orange) – 4 pieces
1K – 1 / 2W (black brown, red) – 2 pieces
10 ohms – 1W (brown, black, black) – 4 pieces
270 ohms – 1 / 2W (red, violet, brown) – 2 pieces
10K – 1 / 2W (brown, black, orange) – 2 pieces
330 ohms – 1 / 2W (orange, orange, brown) – 2 pieces
56 ohms – 1 / 2W (green, black) – 2 pieces
27 ohms – 1W (red, violet, black) – 2 pieces
820 ohms – 1 / 2W (gray, red, brown) – 2 pieces
0.47 ohms – 5W – 8 pieces

Capacitors:

0.1uF/100v – 4 pieces
47uF/63v – 2 pieces
2.2uF/100v – 2 pieces
330pF (ceramic) – 2 pieces
4700uF/63v – 2 pieces

Miscellaneous:

Diode 1N4004 – 10 pieces
Diode P600J – 4 pieces
2 coils of 10 turns with 1/4 copper core 18.
7 amp 33x33v transformer – 2 pieces

400W RMS Stereo Power Amplifier Top PCB Design

Power Supply Schematic for 400W RMS Stereo Power Amplifier

The power supply circuit is simple, you may use 10A transformer and 6800uf of capacitor. The diode value refer to the current value from transformer and it should be have higher value. For example if you use 7A transformer, then use 10A diodes.

Input Connection with Volume Control

This is the input connection for 400W RMS stereo power amplifier with volume control using a stereo potensiometer.

Here is the 250W RMS power amplifier circuit called Legend-Stage Master. This is the previous version of Legend-Stage Master MK2. The circuit is based on power MOSFET and give a great output performance for indoor audio sound system.

Over time there is a need for a stronger version of the legend and which serves to lower sound system for gigs and house parties. This gave improvement to this version called Stage Master which is basically not much different from the original. However, the yield and reliability of the power it was necessary to add a degree of excitation, because the output is assigned to two more pairs of MOSFETs, but the total need for excitation and the other parameters increased because of the parallel connection of so many of FET via abilities were VAS the degree of the basic versions.

Specifications:

> Output power : 250W RMS / 8 ohms
> Frequency range : 12Hz-230KHz (-1dB) at 10W RMS
> THD <0.12% (at 1 kHz and 250 W) > THD <0.01% (at 1 kHz and 200W and below this power) > BIAS around 50mA per output pair

250W RMS Power Amplifier PCB Design and Layout

This is the PCB design and component placement for 250 RMS power amplifier, Legend-Stage Master version. In the design, the MOSFETs are both mounted on the PCB and heatsink. If you have difficulty making appropriate heatsink to be mounted on the PCB, you can separate the heatsink from the PCB, mount the MOSFET on the heatsink, then connect the pins of the MOSFET to a PCB using cable.

This circuit designed by Dr Borivoje Jagodic >> original page for the reference.

This is 500W RMS power amplifier circuit design, build based on MOSFET. The circuit is very popular in EE audio hobbyist as “LEGEND stage Master MK2”. It is a very good and powerful amplifier. It uses 12x power MOSFET IRFP240.

To achieve even greater power, and they were often interested young friends, was developed even stronger version is capable of producing a full and true 500W RMS into 8 ohms. With such large forces had to resort to a radically different solution some degree, for even better reliability, or has increased the complexity of the tiles so that for this version is impossible to use the same tile as the previous two lower models (Legend and Legend Stage Master).

Specification:

Output power ——— 500W RMS / 8 ohms
Frequency range 15Hz-130kHz (-1dB) at 30W RMS
THD = <0.18% (at 1 kHz and 500 W)
THD = <0.01% (at 1 kHz and 400W and below this power)
BIAS around 25mA per output pair

500W RMS Power Amplifier PCB Design and Layout

This is the PCB design and component placement, you should mount the MOSFET on the heatsink to prevent overheating and maintain the performance of power amplifier.

This circuit designed by Dr Borivoje Jagodic >> original page for the reference.

This is a small 12W audio amplifier over a load of 8 Ω, that combining the NE5534 integrated with a pair of V-MOSFET transistor output stage technology as we get excellent sound performance. MOSFET 2SK135 / 2SJ50 from Hitachi is used in this circuit. Input sensitivity of the circuit is 3V RMS maximum, the distortion factor is 0.002% at 1 kHz, and the frequency response is 15 Hz to 100 kHz. (-3dB).

This circuit requires a symmetrical (dual polarity) power supply with voltage output +/- 25V and the current output should be 2A maximum.

12W Audio Amplifier Components List:

Power Supply Specification:
Voltage: Symmetrical 25V
Current : 1A – 2A Max

MOSFET 2SK135 and 2SJ50 Datasheet Downloads:

SK133, SK134, SK135 Datasheet

1 file(s) 192.12 KB

Download

2SJ48, 2SJ49, 2SJ50 Datasheet

1 file(s) 193.15 KB

Download

This is the circuit diagram of 2000W class AB power amplifier uses 7 pairs MJ15003 and MJ15004 transistors for the final amplification block. The circuit operated with 90V DC symmetrical (dual polarity) power supply circuit. The transistors must be mounted on heatsink to prevent the overheating, maintain the transistors work in maximum performance.

2000W Class AB Power Amplifier Specifications:

• Max. Output Peak Power: 2000 Watt Peak @ 2?Ohms Loudspeaker
• Max. RMS Output RMS Power: 1000 Watt RMS @ 2?Ohms Loudspeaker
• Max. Bridged RMS Output Power: 2000 Watt RMS @ 4?Ohms Loudspeaker
• RMS Output Magnitude: 44.7v RMS
• Peak Output Magnitude: 65v Peak
• Freq. Response: 20Hz ~ 20KHz
• Max. Output Gain: 40dB
• Input: 100mV Peak
• DC Power Supply: 90v DC (Dual Supply)

Download the schematic diagram in PDF document for higher image resolution:

2000W Power Amp Schematic PDF

1 file(s) 0.00 KB

Download

Goodluck