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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10 W Audio Amplifier Rise

This design is based on the 18 Watt Audio Amplifier, and was developed mainly to satisfy the requests of correspondents unable to locate the TLE2141C chip. It uses the widespread NE5532 Dual IC but, obviously, its power output will be comprised in the 9.5 - 11.5W range, as the supply rails cannot exceed ±18V.

10 W Audio Amplifier Circuit Diagram

As amplifiers of this kind are frequently used to drive small loudspeaker cabinets, the bass frequency range is rather sacrificed. Therefore a bass-boost control was inserted in the feedback loop of the amplifier, in order to overcome this problem without quality losses. The bass lift curve can reach a maximum of +16.4dB @ 50Hz. In any case, even when the bass control is rotated fully counterclockwise, the amplifier frequency response shows a gentle raising curve: +0.8dB @ 400Hz, +4.7dB @ 100Hz and +6dB @ 50Hz (referred to 1KHz).

Notes:

• Can be directly connected to CD players, tuners and tape recorders.
• Schematic shows left channel only, but C3, C4, IC1 and the power supply are common to both channels.
• Numbers in parentheses show IC1 right channel pin connections.
• A log type for P2 will ensure a more linear regulation of bass-boost.
• Do not exceed 18 + 18V supply.
• Q3 and Q4 must be mounted on heatsink.
• D1 must be in thermal contact with Q1.
• Quiescent current (best measured with an Avo-meter in series with Q3 Emitter) is not critical.
• Set the volume control to the minimum and R3 to its minimum resistance.
• Power-on the circuit and adjust R3 to read a current drawing of about 20 to 25mA.
• Wait about 15 minutes, watch if the current is varying and readjust if necessary.
• 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 C9 to the output ground.
• Then connect separately the input and output grounds to the power supply ground.

Parts:

P1_________________22K Log.Potentiometer (Dual-gang for stereo)
P2________________100K Log.Potentiometer (Dual-gang for stereo)
R1________________820R 1/4W Resistor
R2,R4,R8____________4K7 1/4W Resistors
R3________________500R 1/2W Trimmer Cermet
R5_________________82K 1/4W Resistor
R6,R7______________47K 1/4W Resistors
R9_________________10R 1/2W Resistor
R10__________________R22 4W Resistor (wirewound)

C1,C8_____________470nF 63V Polyester Capacitor
C2,C5_____________100µF 25V Electrolytic Capacitors
C3,C4_____________470µF 25V Electrolytic Capacitors
C6_________________47pF 63V Ceramic or Polystyrene Capacitor
C7_________________10nF 63V Polyester Capacitor
C9________________100nF 63V Polyester Capacitor

D1______________1N4148 75V 150mA Diode

IC1_____________NE5532 Low noise Dual Op-amp

Q1_______________BC547B 45V 100mA NPN Transistor
Q2_______________BC557B 45V 100mA PNP Transistor
Q3_______________TIP42A 60V 6A PNP Transistor
Q4_______________TIP41A 60V 6A NPN Transistor

J1__________________RCA audio input socket

Power supply parts:

R11_________________1K5 1/4W Resistor

C10,C11__________4700µF 25V Electrolytic Capacitors

D2________________100V 4A Diode bridge
D3________________5mm. Red LED

T1________________220V Primary, 12 + 12V Secondary 24-30VA Mains transformer

PL1_______________Male Mains plug

SW1_______________SPST Mains switch

Technical data:

Output power:

10 Watt RMS into 8 Ohm (1KHz sinewave)

Sensitivity:

115 to 180mV input for 10W output (depending on P2 control position)

Frequency response:

See Comments above

Total harmonic distortion @ 1KHz:

0.1W 0.009% 1W 0.004% 10W 0.005%

Total harmonic distortion @ 100Hz:

0.1W 0.009% 1W 0.007% 10W 0.012%

Total harmonic distortion @ 10KHz:

0.1W 0.056% 1W 0.01% 10W 0.018%

Total harmonic distortion @ 100Hz and full boost:

1W 0.015% 10W 0.03%

Max. bass-boost referred to 1KHz:

400Hz = +5dB; 200Hz = +7.3dB; 100Hz = +12dB; 50Hz = +16.4dB; 30Hz = +13.3dB

Unconditionally stable on capacitive loads

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4 x 50 W multifunction quad power amplifier with built in diagnostics feature

Features:

■ Multipower BCD technology

■ MOSFET output power stage

■ DMOS power output

■ New high efficiency (class SB)

■ High output power capability 4 x 28 W / 4  @ 

14.4 V, 1 kHz, 10 % THD, 4 x 50 W max power 

■ Max. output power 4 x 72 W / 2 

■ Full I2C bus driving:

– Standby

– Independent front/rear soft play/mute

– Selectable gain 30 dB / 16 dB (for low noise 

line output function)

– High efficiency enable/disable

– I2C bus digital diagnostics (including DC 

and AC load detection)

■ Full fault protection

■ DC offset detection

■ Four independent short circuit protection

■ Clipping detector pin with selectable threshold 

(2 % / 10 %)

■ Standby/mute pin

■ Linear thermal shutdown with multiple thermal 

warning

■ ESD protection

Description:

The TDA7563B is a new BCD technology quad bridge type of car radio amplifier in Flexiwatt27 & PowerSO36 packages specially intended for car radio applications. Thanks to the DMOS output stage the TDA7563B has a very low distortion allowing a clear powerful sound. Among the features, its superior efficiency performance coming from the internal exclusive structure, makes it the most suitable device to simplify the thermal management in high power sets. The dissipated output power under average listening condition is in fact reduced up to 50 % when compared to the level provided by conventional class AB solutions.

This device is equipped with a full diagnostics array that communicates the status of each  speaker through the I2C bus.

Circuit Diagram:

4 x 50 W multifunction quad power amplifier  with built-in diagnostics feature

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4 x 11 W single ended or 2 x 22 W power amplifier with distortion detector

GENERAL DESCRIPTION

The TDA1555Q is an integrated class-B output amplifier in a 17-lead single-in-line (SIL) plastic power package. The circuit contains 4 x 11 W single-ended or 2 x 22 W bridge amplifiers. The device is primarily developed for car radio applications.

Features

• Requires very few external components
• Flexibility in use − Quad single-ended or stereo BTL
• High output power
• Low offset voltage at outputs (important for BTL)
• Fixed gain
• Good ripple rejection
• Mute/stand-by switch
• Load dump protection
• AC and DC short-circuit-safe to ground and VP
• Thermally protected
• Reverse polarity safe
• Capability to handle high energy on outputs (VP = 0 V)
• Protected against electrostatic discharge
• No switch-on/switch-off plop
• Low thermal resistance
• Identical inputs (inverting and non-inverting)
• Flexible leads
• Distortion detector

Circuit Diagram:

TDA1555Q 4 x 11 W single-ended 

TDA1555Q 2 x 22 W power amplifier with distortion detector

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12 W car radio power amplifier

General Description

The TDA1020 is a monolithic integrated 12 W audio amplifier in a 9-lead single in-line (SIL) plastic package. The device is primarily developed as a car radio amplifier. At a supply voltage of VP= 14,4 V, an output power of 7 W can be delivered into a 4 Ω load and 12 W into 2 Ω. To avoid interferences and car ignition signals coming from the supply lines into the IC, frequency limiting is used beyond the audio spectrum in the preamplifier and the power amplifier. The maximum supply voltage of 18 V makes the IC also suitable for mains-fed radio receivers, tape recorders or record players. However, if the supply voltage is increased above 18 V (< 45 V), the device will not be damaged (load dump protected). Also a short-circuiting of the output to ground (a.c.) will not destroy the device. Thermal protection is built-in. As a special feature, the circuit has a low stand-by current possibility.

Circuit Diagram:

12 W car radio power amplifier

Datasheet for TDA1020: Download

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