Power Amplifier MOSFET 360 W

I propose here a more powerful version of the 200 Wrms 8 ohms AB class power amplifier project. It shares the same concept that the less poweful model : assembled using common compoments (not very expensive), based on traditional diagrams : a symmetrical differential input stage, a cascode stage driver and a MOSFET output stage. The printed circuit board is very compact , and is composed of two subsets : the command stage and the output stage. All resistors are 1/4 watt 1 % metal film (except if otherwise stated). Constant current sources of +/- 1 mA are formed around T5 and T6. The diodes D1 to D6 allow the use of low noise transistors type BC550C and BC560C, the transistors T7 to T10 form the stage driver. The potentiometer P1 allows the adjustment of the quiescent current to 100 mA per output transistor. The symmetrical power supply is entrusted to a large transformer of 750 VA, 2 * 60 volts + bridge rectifier and 8 reservoir capacitors of 4700 µF, which gives an output voltage of + and - 85 volts per rail. A 1000 VA transformer is necessary for maximal continuous output power at 4 ohms. The output power is 360 Wrms under 8 ohms or 550 Wrms under 4 ohms. Distortion is lower than 0,02 %, damping factor is better than 400, signal-noise ratio is 112 db (balanced A at full power), the input sensitivity is 1,2 volts (360 W under 8 ohms).

Diagram : 

The capacitor C3 is not reproduced on the diagram and on the PCB (it is correct).

Proposal of the command stage PCB : 

 
Transistors T9 and T10 must be assembled on a common heatsink with 5° c/w thermal resistance or on the output stage heatsink.

Proposal of the output stage PCB : 

 The points marked A, B and C have to be connected between the two PCBs. The ground (earth) points of PCBs and loudspeaker ground (earth) must compulsorily be connected in star with the 0 Volts of the PSU. The power transistors must be assembled on a heatsink with a termal resistance less than 0.5 ° C/W. They must also be electrically insulated from the heatsink by using a mica insulator + heat-conducting compound or a silicone insulator.

Bandwidth : 

Bandwidth is limited from 5 Hz to 53 Khz (at - 3 db) by the input module (C1, R1, C2, R2). It can be modified according to the application desired. It is useless to increase the bandwidth to the botton (bass) because little useful signal is present at the bottom of the spectrum. In public address sound systems the bandwidth is often limited between 20 and 35 Hz. The loudspeakers are thus protected against too high extreme-bass signals and some more power is available for the remainder of the spectrum. Michael Eveleigh (UK)

 Source : http://users.swing.be/edwinpaij/ampli_mosfet_360_w.htm

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Mosfet Power Amplifier 100 Watt

At this time a unsophisticated MOSFET amplifier or else power Amp which Output power is plus/minus 100 Watt/RMS with 8 Ohms otherwise ohter plus/minus 160 Watts /RMS with 4 ohms.

Mosfet Amplifier 100 Watt RMS

Regarding this circuit simplicity, The distortion is plus/minus 0.1 %. In support of mob-width -3 db(decibel) is increase for 4 Hz to 96 Khz, it is narrow by C1, R1, C2 and R2. Taking part in the two transistors are T1 and T2 makes a initial differential stage part, So,current source(I) of +/- solitary mA is put with resistor R3. In favor of the upgraded project, The current source(I) is new efficient in stability. Coil P1 allows a fine tuning of dictate current voltage on amplifier’s output. Place the Coil P1 with it’s partially usefulness in favor of first power up, so therefore break it unhurriedly for a lowest DC output voltage. custom a essential quality compoment.

Electronic Part

C1 = 2,2 µF MKP, MKT 100 in opposition to

C2 = 330 pF céramique 50 V

C3 = 100 nF MKP, MKT 100 in opposition to

C4 = 100 µF 40 V électro-chimique

C5, C6 = 18 pF céramique 50 vs.

C7 = 100 nF MKP, MKT 250 V  (C8 = 47 µF 100 V)

R1, R3 = 47 K   (R3 = 330 -> 470 Ohms)

R2 = 2K2

R4, R5 = 3K9

R6 = 1 K

R7 = 27 K

R8, R9, R11 = 100 ohms

R10 = 10 K

R12, R13 = 470 ohms

R14, R15 = 0.33 ohms 5 watts

R16 = 10 ohms 3 watts      (R17 = 1 K    R18, R19 = 10K)

T1, T2, T9,T10 = 2SD756A,2SD716A, BC556B (attention au brochage différent - take be concerned representing pin arrange)

T7 = IRFP240, 2SK1530, 2SJ162, BUZ900DP, BUZ901DP (attention au brochage dissimilar - take care for pin layout : GDS GSD)P1 = 100 ohms  (25 turns - 25 turns)

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400W High Power Mosfet Amplifier

High Power Amplifier Mosfet 400W . These amplifiers circuit can be used for virtually any application that requires high performance, low use Noise, distortion and excellent sound quality. Examples would be subwoofer amplifier should FOH stage Amplifiers, surround a canal a very powerful sound amplifier, etc. The 400W MOSFET-amplifier has four key stages of amplification. We are looking to start any Phase appropriate detail.

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