5/27/2014

2x12 W hi-fi audio power amplifiers with mute

General Description for TDA2616Q:
 

The TDA2616 and TDA2616Q are dual power amplifiers. The TDA2616 is supplied in a 9-lead single-n-line (SIL9) plastic power package (SOT131), while the TDA2616Q is supplied in a 9-lead SIL-bent-to-DIL plastic power package (SOT157). They have been especially designed for mains fed pplications, such as stereo radio and stereo TV.

Features:

• Requires very few external components
• No switch-on/switch-off clicks
• Input mute during switch-on and switch-off
• Low offset voltage between output and ground
• Excellent gain balance of both amplifiers
• Hi-fi in accordance with IEC 268 and DIN 45500
• Short-circuit proof and thermal protected
• Mute possibility

Circuit diagram for TDA2616:

2x12 W hi-fi audio power amplifiers with mute TDA2616


Datasheet for TDA2616: Download

5/26/2014

30W bridge car radio amplifier TDA7256

Description of TDA7256:

The TDA7256 is a class AB fully protected bridge power amplifier designed for car radio application. The high current capability allows to dirve low impedance loads up to 22 Ohm. The differential inputs availability makes it particularly suitable for boosters and active loudspeakers applications

Features of TDA7256:
  • NO AUDIBLE POP DURING MUTE AND
  • STANDBY OPERATIONS
  • MUTING TTL COMPATIBLE
  • VERY LOW STANDBY CONSUMPTION
  • PROGRAMMABLE TURN ON DELAY
  • DIFFERENTIAL INPUT
  • SHORT CIRCUIT PROTECTIONS:
  • RL SHORT - OUT TO GROUND - OUT TO VS
  • OTHER PROTECTIONS:
  • Load dump voltage surge
  • LoudspeakerDC current
  • Very inductive load
  • Overrating temperature
  • Open ground
Circuit diagram for TDA7256:

30W bridge car radio amplifier TDA7256 circuit diagram
 PCB and layout for TDA7256:
30W bridge car radio amplifier TDA7256 pcb 

 PCB and layout for TDA7256: Download



5/24/2014

Subwoofer Design - Bandpass Dual Chamber

Bandpass Dual Chamber Basic Theory:

The front and rear of the driver are mounted in separate enclosures and tuned to specific calculated values. Resultant output is suppose to be better than any of the other designs mentioned previously. Bose owns the rights to the exact details behind this design. They explain the theory like this, "The low-frequency speaker drivers are located between separate acoustic compression chambers inside a patented Bose Acoustimass module. As each speaker cone moves, it excites air in the chambers. Trapped in the chamber, this air acts as an acoustic spring, which interacts with the air in the port to produce more low-frequency sound with less power. The system is more efficient and requires less cone motion, which in turn produces less distortion. In the event that any otherwise audible distortion is produced, the patented design traps it inside the acoustic chambers -- so it never enters the room. The result is an Acoustimass module with no audible distortion that can be located anywhere in the listening area.

Bandpass Dual Chamber Advandages:
More efficient system within its bandpass. More control over cone movement. Less audible distortion. This doesn't necessarily mean that there is a true reduction in distortion from the driver, but that any distortion that is present form the driver can't be heard as well due to the chambers acting as filters on any unwanted noise. My opinion only.

Bandpass Dual Chamber Disadvandages:
Combined volume of both chambers may result in large overall enclosures. Very difficult to design properly. You may have to experiment a great deal before getting this design to sound acceptable. Results may vary substantially due to misalignment of both front and rear chambers as well as tuning frequency of each chamber. Drivers can be easily blown due to high compression factors because of lowered cone motion and thereby exceeding the thermal limits of the driver before exceeding its mechanical limits. The driver may in fact tear itself to pieces. There are no exact parameters or calculations for designing 6th order bandpass enclosures due to the patent owned by Bose. So if you build one, you're basically on your own. Original article sourse is danmarx.org.

Subwoofer Design - Order Vented

Order Vented Basic Theory:
Also known as bass-reflex, ported or vented. The driver is mounted into an enclosure which houses a large opening, port, vent or slot that extends into the cabinet a specified length. The length and area of this vent are extremely critical to the proper function of a 4th order enclosure. The port and driver contribute together to provide the desired response characteristic. The driver is generally mounted with the front facing outwards, but is not restricted to this method only. The vent which extends into the cabinet tunes the enclosure to a specific frequency (known as fB) thereby acting as a high pass filter on the driver. Driver excursion is at its minimum at fB where the vent then takes over and provides most of the output. Cut-off rate below fB is 24 dB/octave but can be varied up or down 5-6 dB depending upon the exact tuning frequency and volume of the enclosure. There are various types of alignments that all fit into the ported 4th
order category. Some common types are QB3, EBS, SBB4 and SC4. By varying the enclosure size and the tuning frequency, it is possible to achieve a variety of distinct low- frequency performances from a single driver. The vent acts by damping the load produced by the driver above fB causing it to behave somewhat as if it were in a sealed enclosure. Best suited for drivers with an EBP near 100.0 or higher and Qts < 4.0 but is not restricted to these numbers only.

Order Vented Advandages:
Extended low frequency response. 3 dB down points (f3) are capable of being near or even below 20 Hz. Increased power handling above fB due to reduced driver excursion at and while nearing fB. More efficient system. Generally +3dB increased output over sealed enclosures due to the combined output of driver and port. More overall SPL capabilities. Deep, powerful, full, loud, inspiring, incredible, and earth shattering are common subjective terms associated with vented enclosures.

Order Vented Disadvandages:
Larger enclosure size. More difficult to accurately achieve predicted results. Misaligned enclosures can result in very poor bass quality. Very accurate T/S parameters of actual driver is required. Although sometimes you can get away with using manufacture’s specifications. Driver unloading or bottoming out below fB is very common. Xmax is reached easily below fB and may cause sever damage the the driver's suspension, voice coil or cone. This usually requires the need to install additional high pass filtering below fB. But is not a always a necessity as long as power levels and frequency content are kept within reason. Transient response is degraded, yielding typical group delay curves as high as 50 ms. Muggy, boomy, sluggish, one-note, slow, and inaccurate are common subjective terms associated with vented enclosures. Port diameter must be large to avoid unwanted port noise, which in turn requires the port to be long for any given Fb, which then drives up the volume of the enclosure, sometimes to undesirably large proportions. Port chuffing if port area is not kept in check.
Order Vented Best Applications:

Where the deepest and loudest bass is necessary. Where size is not a huge issue but may still be a definite factor. For Home Theater and music. May be best suited for sound reinforcement, theater, live performances, DJ and other situations where lots of loud deep bass is needed and transient response is less critical.

Subwoofer Design - Order Acoustic Suspension

Order Acoustic Suspension Basic Theory:

The driver is mounted in a sealed, airtight enclosure, generally with the front of the driver facing outward but is not restricted to this method only. The volume of the enclosure is chosen to achieve a desired system Q which defines the response characteristics of the driver and enclosure. Q values may range between the 0.5 and 1.5 - with 0.5 being overdamped, 1.5 being underdamped, and 0.7 being critically damped or flat. The total system Q (also known as Qtc) is dependent on 3 things: the volume of enclosure, the T/S parameters of driver and internal treatment compounds. A a general rule only, sealed enclosures may be best suited for drivers with an EBP (Efficiency Bandwidth Product) of 50.0 or lower and drivers with Qts values above 0.40 but is not restricted to these exact values. EBP is calculated by taking the the fs of the driver and dividing it by the Qes - therefore EBP = fs/Qes. The cutoff rate is typically 12 dB/octave below f3, however higher system Q's result is a somewhat sharper roll-off (~14 dB/octave) while lower system Q's result in a slightly more shallow roll-off (~10 dB/octave). Better damping and better transients are achieved by shooting for a lower system Q which can
be accomplished by either making the enclosure larger or by adding stuffing/damping material. Suitable damping materials include polyfill, Dacron, fiberglass, and acoustic foam. Box stuffing will also affect f3 by either raising it or lowering it depending upon the type and amount of stuffing used. Stuffing makes the box "appear" to be acoustically larger than it really is.

Order Acoustic Suspension Advandages:

2nd order sealed enclosures are simple to design and offer outstanding performance in a wide variety of applications. They are easy to model with software and get predicted results. Box size and shape are generally the least complex. Great for both beginning and advanced DIY’ers. The exact desired response characteristics can be achieved by simply designing for a particular Qtc (or system Q). Modeled performance is easily altered by varying the size of the enclosure and/or the amount of stuffing material used. They exhibit a very shallow cutoff rate of 12 db/octave below fB. This results in much better group delay response. Fast, quick, natural, smooth, tight, accurate, controlled and warm are some common subjective terms one might use to describe sealed enclosures. Transient response is the best of all enclosure types. The excursion of the driver increases as the frequency applied decreases until fB is reached after which the driver excursion begins to decrease. There is typically no need for subsonic filtering due to the enclosure’s natural tendency to inhibit extremely low frequencies. This results in less bottoming out of drivers at subsonic frequencies. However, this only applies for smaller enclosures. As the enclosure size gets larger, more Xmax is required in order to prevent overexertion for the same amount of input power. Sealed enclosures have more extended low frequency response than vented enclosures given the same f3 for both due to the shallower rate of roll-off. Phase shift is minimal within its normal operating frequency range.

Order Acoustic Suspension Disadvandages:
Very low frequency output is difficult to achieve without active filtering. The f3 (also know as 3dB down point) is usually fairly high, above 30 Hz in most applications and by simply increasing Vb, one cannot lower f3 for any given driver. Low f3's in a sealed enclosure can be achieved by using drivers with a very low free air resonance or Fs. Less power efficient by about -3 dB as compared with vented enclosures. Lower over SPL capabilities. There's a strong need for drivers with a very large Xmax in order to ensure safe operation at least down to fB, especially if the box is designed for Qtc values < 0.7 Any enclosure volume that is modeled with the system Q larger than 0.707 results in higher f3. Lowest f3 is achievable only under an ideal Q = .707 alignment which may require unusually large and sometimes undesireable enclosure volumes.

Order Acoustic Suspension Best Applications:
Best suited where a completely uncompromised sound quality is desired. Best for classical music and most rock and pop type music. Most widely used in car stereo systems where cabin gain can make up for its lack of low end <30Hz bass. Where size is an issue. Sealed boxes can be half the size of vented boxes yet can be made even smaller if a higher Q is allowed. May also be use for small to moderately sized Home Theaters. Usually is the easiest box to pass SAF (spouse acceptance factor). You should also go with sealed when the driver's T/S parameters dictate that the driver should be housed in a sealed enclosure due to a high Qts (above 0.4) or an EPB of 50 or lower - though this just a guideline and not a rule. Original article sourse is danmarx.org.

5/21/2014

80W Subwoofer Amplifier TDA7295

General Description Subwoofer Amplifier TDA7295:
The 80W Subwoofer Amplifier TDA7295 is a monolithic integrated circuit in Multiwatt15 package, intended for use as audio class AB amplifier in Hi-Fi field applications (Home Sterio, self powered loudspeakers, Top-class TV). Thanks to the wide voltage range and to the high uot current capability it is able to suply the highest power into both 4 Ohm and 8 Ohm loads even in presence of poor supply regulation, with high Supply Voltage Rejection. The Built in muting function with turn on delay simplifies the remote opeeration avoiding switching on-off noises.

Features of TDA7295:
  • Very high operating voltage range (+-40V)
  • Dmos Power Stage
  • Very low distortion
  • Very low noise

Circuit diagram for TDA7295:
80W Subwoofer Amplifier TDA7295

Layout and pcb for TDA7295:
TDA7295 pcb layout
Datasheet for TDA7295: Download




5/20/2014

TDA8510J power amplifiers 2 x 13 + 26W

General Description for TDA8510J:


The TDA8510J is an integrated class-B output amplifier in a 17-lead single-in-line (SIL) power package. It contains a 26 W Bridge-Tied Load (BTL) amplifier and 2 × 13 W Single-Ended (SE) amplifiers. The device is primarily developed for multi-media applications and active speaker systems (stereo with subwoofer).


Features of TDA8510J:
  • Requires very few external components
  • High output power
  • Low output offset voltage (BTL channel)
  • Fixed gain
  • Diagnostic facility (distortion, short-circuit and temperature detection)
  • Good ripple rejection
  • Mode select switch (operating, mute and standby)
  • AC and DC short-circuit safe to ground and to VP
  • Low power dissipation in any short-circuit condition
  • Thermally protected
  • Reverse polarity safe
  • Electrostatic discharge protection
  • No switch-on/switch-off plop
  • Flexible leads
  • Low thermal resistance
  • Identical inputs (inverting and non-inverting)..

Circuit diagram for TDA8510J:
TDA8510J power amplifiers 2 x 13 + 26W

Datasheet for TDA8510J: Download
Where you can buy TDA8510J: Aliexpress

5/12/2014

TDA8559T Low-voltage stereo headphone amplifier



General description for TDA8559T:

The TDA8559T is a stereo amplifier that operates over a wide supply voltage range from 1.9 V to 30 V and consumes a very low quiescent current. This makes it suitable for battery fed applications (2 × 1.5 V cells). Because of an internal voltage buffer, this device can be used with or without a capacitor connected in series with the load. It can be applied as a headphone amplifier, but also as a mono amplifier with a small speaker (25 Ω), or as a line driver in mains applications.

Features for TDA8559T:

  • Operating voltage from 1.9 V to 30 V
  • Very low quiescent current
  • Low distortion
  • Few external components
  • Differential inputs
  • Usable as a mono amplifier in Bridge-Tied Load (BTL) or stereo Single-Ended (SE)
  • Single-ended mode without loudspeaker capacitor
  • Mute and Standby mode
  • Short-circuit proof to ground, to supply voltage (< 10 V) and across load
  • No switch on or switch off clicks
  • SD protected on all pins

Applications for TDA8559T:

  • Portable telephones
  • MP3 players
  • Portable audio
  • Mains fed equipment
Circuit diagram for TDA8559T:

PCB layout for TDA8559T:


Datasheet for TDA8559T: Download


5/11/2014

12W single-ended car radio power amplifier with diagnostic interface

General Description for TDA8565Q:


The TDA8565Q is an integrated class-B output amplifier in a 17-lead DIL-bent-to-SIL power package. It contains 4 × 12 W single-ended amplifiers.

Features of TDA8565Q:



  • Requires very few external components
  • High output power
  • Fixed gain
  • Diagnostic facility (distortion, short-circuit andtemperature detection)
  • Good ripple rejection
  • Mode select switch (operating, mute and standby)
  • Load dump protection
  • AC and DC short-circuit safe to ground and to VP
  • Low power dissipation in any short-circuit condition
  • Thermally protected
  • Reverse polarity safe
  • Electrostatic discharge protection
  • No switch-on/switch-off plop
  • Flexible leads
  • Low thermal resistance
  • Identical inputs.
Circuit digram for TDA8565Q:
12W single-ended car radio power amplifier with diagnostic interface

Datasheet for TDA8565Q: Download
Where you can buy: Aliexpress

TDA8566 2x40 W/2 Ω stereo BTL car radio power amplifier

Description of TDA8566:

The TDA8566 is an integrated class-B output amplifier which is available in several packages. TDA8566TH is contained in a 20-lead small outline plastic package. The  TDA8566TH1 is a 24-lead small outline plastic package which is pin compatible with the 2C-bus controlled amplifier TDA1566TH for one board layout. TDA8566Q is a 17-pin DIL-bent-SIL package. The device contains 2 amplifiers in a Bridge-Tied Load (BTL) configuration. The output power is 2 × 25 W in a 4 Ω load or 2 × 40 W in a 2 Ω load. It has a differential input stage and 2 diagnostic outputs. The device is primarily developed for car radio applications.

Features TDA8566:
  • Differential inputs
  • Very high Common Mode Rejection Ratio (CMRR)
  • High common mode input signal handling
  • Requires very few external components
  • High output power
  • 4 Ω and 2 Ω load driving capability
  • Low offset voltage at output
  • Fixed gain
  • Diagnostic facility (distortion, short-circuit and temperature pre-warning)
  • Good ripple rejection
  • Mode select switch (operating, mute and standby)
  • Load dump protection
  • Short-circuit proof to ground, to VP and across the load
  • Low power dissipation in any short-circuit condition
  • Thermally protected
  • Reverse polarity safe
  • Protected against electrostatic discharge
  • No switch-on/switch-off plops
  • Low thermal resistance
  • TDA8566TH1 is pin compatible with TDA1566TH

Applications:
  • Home-sound sets 
  • Multimedia systems 
  • Car audio (boosters)
Circuit diagram TDA8566:

TDA8566 2 × 40 W/2 Ω stereo BTL car radio power amplifier with differential inputs and diagnostic outputs

Datasheet for TDA8566Download
Where you can buy: Aliexpress
Where you can buy: DealExtreme

TDA8920 2x100W class-D power amplifier

Description of TDA8920:

The TDA8920B is a high efficiency class-D audio power amplifier with very low dissipation. The typical output power is 2 × 100 W. The device is available in the HSOP24 power package and in the DBS23P through-hole power package. The amplifier operates over a wide supply voltage range from ±12.5 V to ±30 V (±32 V non operating) and consumes a very low quiescent current. The TDA8920B is a two channel audio power amplifier using class-D technology. The audio input signal is converted into a digital pulse width modulated signal via an analog input stage and Pulse Width Modulation (PWM) modulator. To enable the output power transistors to be driven, this digital PWM signal is applied to a control and handshake block and driver circuits for both the high side and low side. In this way a level shift is performed from the low power digital PWM signal (at logic levels) to a high power PWM signal which switches between the main supply lines. A 2nd-order low-pass filter converts the PWM signal to an analog audio signal across the loudspeakers. The TDA8920B one-chip class-D amplifier contains high power D-MOS switches, drivers, timing and handshaking between the power switches and some control logic. For protection a temperature sensor and a maximum current detector are built-in. The two audio channels of the TDA8920B contain two PWM modulators, two analog feedback loops and two differential input stages. It also contains circuits common to both channels such as the oscillator, all reference sources, the mode functionality and a digital timing manager.

Features TDA8920:
  • Zero dead time switching 
  • Advanced current protection: output current limiting 
  • Smooth start-up: no pop noise due to DC offset 
  • High efficiency 
  • Operating supply voltage from ±12.5 V to ±30 V 
  • Low quiescent current 
  • Usable as a stereo Single-Ended (SE) amplifier or as a mono amplifier in Bridge-Tied Load (BTL) 
  • Fixed gain of 30 dB in Single-Ended (SE) and 36 dB in Bridge-Tied Load (BTL) 
  • High output power 
  • High supply voltage ripple rejection 
  • Internal switching frequency can be overruled by an external clock 
  • Full short-circuit proof across load and to supply lines 
  • Thermally protected

Applications:
  • Television sets 
  • Home-sound sets 
  • Multimedia systems 
  • All mains fed audio systems 
  • Car audio (boosters)

Circuit diagram TDA8920:
TDA8920 2x100W class-D power amplifier
   

Datasheet for TDA8920Download
Where you can buy: Aliexpress
Where you can buy: DealExtreme

5/06/2014

TDA1011 2 to 6 W audio power amplifier

Description:

     The TDA1011 is a monolithic integrated audio amplifier circuit in a 9-lead single in-line (SIL) plastic package. The device is especially designed for portable radio and recorder applications and delivers up to 4 W in a 4Ω load impedance. The device can deliver up to 6 W into 4Ω at 16 V loaded supply in mains-fed applications. The maximum permissible supply voltage of 24 V makes this circuit very suitable for d.c. and a.c. apparatus, while the very low applicable supply voltage of 3,6 V permits 6 V applications.

Special features:

  • single in-line (SIL) construction for easy mounting
  • separated preamplifier and power amplifier
  • high output power
  • thermal protection
  • high input impedance
  • low current drain
  • limited noise behaviour at radio frequencies

Reference:

  • Supply voltage range Vp...........................3,6 to 20 V 
  • Repetitive peak output current IORM...........max. 3 A 
  • Operating ambient temperature Tamb ........−25 to + 150 °C 
  • Storage temperature Tstg ........................−55 to + 150 °C 

Circuit diagram:
TDA1011 circuit diagram

TDA1011 layout

TDA1011 pcb


    

Datasheet for TDA1011A: Download
Where you can buy: Aliexpress

TDA1010A 2 x 6W audio power amplifier

Description:

     The TDA1010A is a monolithic integrated class-B audio amplifier circuit in a 9-lead single in-line (SIL) plastic package. The device is primarily developed as a 6 W car radio amplifier for use with 4Ωand 2Ωload impedances. The wide supply voltage range and the flexibility of the IC make it an attractive proposition for record players and tape recorders with output powers up to 10 W.

Special features:

  • single in-line (SIL) construction for easy mounting 
  • separated preamplifier and power amplifier 
  • high output power 
  • low-cost external components 
  • good ripple rejection 
  • thermal protection 

Reference:

  • Supply voltage range Vp...........................6 to 24 V 
  • Repetitive peak output current IORM...........max. 3 A 
  • Operating ambient temperature Tamb ........−25 to + 150 °C 
  • Storage temperature Tstg ........................−55 to + 150 °C 

Circuit diagram:
Tda1010A Circuit Diagram

Tda1010A layout

Tda1010A pcb
    

Datasheet for TDA1010A: Download
Where you can buy: Aliexpress

5/04/2014

NE5532 Headphone Amplifier

NE5532 Headphone Amplifier Circuit Diagram:

Partlist for NE5532:
P1 = 22K
R1 = 18K
R2 = 68K
R3 = 68K
R4 = 68K
R5 = 18K
R6 = 68K
C1 = 4.7uF/25v
C2 = 4.7uF/25v
C3 = 22pF
C4 = 220uF/25v
C5 = 220uF/25v
C6 = 4.7uF/25v
C7 = 22pF
C8 = 220uF/25v
J1 = 3.5mm Stereo Jack
B1 = 9V Battery
IC1 = NE5532
SW1 = SPST Toggle Switch

5/03/2014

1000W MOSFET stage Master MK2


1000W MOSFET Description:

Fifth Generation HEXFETs from International Rectifier utilize advanced processing techniques to achieve extremely low on-resistance per silicon area. This benefit, combined with the fast switching speed and ruggedized device design that HEXFET Power MOSFETs are well known for, provides the designer with anextremely efficient and reliable device for use in a wide variety of applications.
The TO-247 package is preferred for comme rcial-industrial applications where higher power levels preclude the use of TO-220 devices. The TO-247 is similar but superior to the earlier TO-218 package because of its isolated mounting hole. The 1000Watt MOSFET LEGEND stage Master MK2 is a very good and powerful amplifier. It is not into the classroom HiEnd sure, but very respectable sounding unit with lots of of power. It was not designed with home interior as the primary goal before, such a power used only rarely in the house and indoor except perhaps in some larger nightclubs. Frankly, due to a high performance, could PA light rather go class, but other specifications and great quality over the PA standards and needs! My only additional suggestion for you to think about it at length, Master internship as a Master MK2.Internship Master 500 ... 1000W, but is aa little easier (and cheaper) to build. "PCB show thus as below 1000W mosfet PCB 1000W mosfet PCB.

1000W MOSFET Circuit Diagram:
1000W MOSFET circuit diagram
1000W MOSFET PCB:
1000W MOSFET pcb
Datasheet for transistors:
  • IRFP260 Datasheet (PDF) - International Rectifier - IRFP260 Click to view 
  • MJE340 Datasheet (PDF) - Motorola, Inc - MJE340 Click to view 
  • MJE350 Datasheet (PDF) - Motorola, Inc - MJE350 Click to view 

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200W Audio Amplifier Circuit

Circuit description: Connecting two TDA2030 thru cheap power transistors we can create a amplifier wich can deliver a higher power. Wi...

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