Another Electronics Circuit Schematics Diagram.

Design Electronics Circuit Diagram Schematics - Constant Current Amplifier

2013-01-30T03:31:00.000+07:00

Continue past article, the constant current amplifier. Time we will discuss design electronics circuit diagram schematics - constant current amplifier is somewhat unique when viewed from the definition itself, I would give a little reference and link to read:

Actually in theory all the amplifiers can be made constant current amplifier but it needs more study in that we get a result that meets your taste and satisfaction.

Basic Electronics circuit diagram - schematics constant current amplifier

Approximately 3 or 5 years ago I had to modify the active speaker to a computer using ic LM3886 and the results are quite satisfactory. Moreover, added flat pre-amplifier from Rod Elliott (ESP) sound so very exciting.

In addition to the power amplifier, I also added a power supply using a capacitance multiplier.

A detailed discussion of these modifications I will write in my next article.

Happy reading.
(acl)

Constant Current Amplifier

2012-06-15T04:42:00.000+07:00

A few days ago my friend came to the house, he shows the constant current amplifier schematics he found in http://www3.ocn.ne.jp/ ~ tima / products / ccamp / ccamp.html. We discuss and discuss until a few days. My friend kept us curious and eager to assemble.

Schematic Constant Current Amplifier Original

Schematic Constant Current Amplifier Modified

Modified schematic

I've assembled Constant Current Amplifier, but I do not really remember very well, probably from DIY Nelson Pass Zen. Constant Current Amplifier quite different from the single-ended Zen or its variants.

After reading and studying the sources of http://www3.ocn.ne.jp/ ~ tima / products / ccamp / ccamp.html and Hen experiment we finally managed to modify it by adding a few components.

In blind tests, the addition of these components produce a sound more amazing.

RX1 and CX1 form the LF filter. RX1 = 100 ohms and RCX1 = 1 nF. = 11 ohm RX2, RX3 = 0.22 ohm 5 Watt and CX2 = 100 nF

Assemble

I have a custom of using 2 Watt carbon resistor brands Phillips and my legs coated with tin WBT. I have done this long ago. I think the use of carbon 2 watt resistor produces a clear sound, more open and get a natural sound.

Therefore, I use a 2 watt resistor all unless otherwise specified.

For power supply I recommend to use A Simple Capacitance Multiplier Power Supply For Class-A Amplifiers Rod Elliott - ESP. I use a voltage source 21 Volts and 90 Volts.

Assemble survived.
(Hopefully in the next article I will discuss it in more detail)

Fet Buffer for amplifiers

2011-07-08T12:13:00.000+07:00

source: http://cappels.org/dproj/edfet/edfet.html

The EDFET drives like a FET, but with the bias stability of bipolar. Amps of output current can be controlled by milliamps of input current. The current gain is a design choice dictated by bandwidth. Two of things you have to consider when adding a power output stage to an op-amp circuit are the frequency response and the cross-over distortion in that stage.

This is especially true with wide band amplifiers, where the unity gain crossover needs to be at several hundred kilohertz. The stage is driven much the same as a complimentary pair output stage, but with the current gain that comes with using FETs., and with feedback within the output stage that that extends the buffer's bandwidth and regulates the quiescent current. More predictable operation allows the designer to design a circuit lower overall power dissipation and better closed loop stability.

The EDFET complimentary buffer is made up of a pair of unity gain buffers, one that drives in the positive direction and the other that drives in the negative direction. Pictured above is the positive driving half of the output stage.

Gain to make the output signal track the input signal comes from inverting transistor, Q1. The input signal is applied to the emitter of Q1 and the output of the amplifier is raised one diode drop to match the forward base-emitter drop of Q1, by diode connected transistor Q2. The buffer's offset is determined by the log of the magnitude of the mismatch in the emitter currents in Q1 and Q2, and it is directly proportional to the absolute temperature.

Since the saturation current usually isn't published for the transistors this expression is only usefully for appreciating the dependence of junction voltage on current and temperature. You can come up with your own value of I0 for a given transistor if you know all the other parameters and solve the above formula for I0. By the way, since, for most practical uses, you will be running at more than a thousand times the saturation current, the "+1" term can be dropped from practical calculations.

As an example, for the audio amplifier using a EDFET buffer shown in Figure 1. The following assumptions are applied: The maximum output voltage is 5 VDC with respect to ground, the power supply (VA) is 12 VDC, the maximum gate voltage is 8 VDC, the input capacitance, Ciss of the BUZ73 is 500 pf, and an...
http://cappels.org/dproj/edfet/edfet.html

Discrete Buffer: Diamond Buffer
Discrete Buffer: JISBOS Buffer

Design Buffers: Improved unity-gain follower delivers fast, stable response

2011-07-08T11:58:00.000+07:00

Robert A Pease, National Semiconductor Corp -- EDN, June 27, 2011

Heavy load capacitance can cause the output of a unity-gain follower—an operational amplifier with direct feedback to the inverting input (Fig 1)—to ring and oscillate. The LM110 follower, for example, normally drives a 50-pF load without problems, but it does not drive 500 pF stably—high capacitance significantly modifies the open-loop output impedance, reducing the phase margin to zero and causing oscillation.

You can easily eliminate such instability problems by adding a capacitor and resistor in series across the op amp's inverting and noninverting inputs. This solution can also greatly improve a follower's slew rate.

Analyze the problem

In general, increasing the ac noise gain of an op amp's feedback network improves capacitive-load tolerance. A common gain-increasing strategy adds R₂~R_F/10 to the circuit shown in Fig 2. (A moderate-value capacitor, C₂, usually inserted in series with R₂, prevents the dc noise gain from also increasing and degrading dc-offset, drift and accuracy specifications.)

If the op amp has a 1-MHz gain-bandwidth product and R₁=R_F, the closed-loop frequency response will be 500 kHz. Inserting R₂=R_F/10 drops this frequency response to 90 kHz, where the amplifier usually tolerates a much larger capacitive load. AC noise gain equals (R_F/ R₁)+(R_F/R₂)+1, and dc noise gain is (R_F/R₁)+1.

You can also increase ac noise gain by installing R₃ and C₃ instead of R₂ and C₂. The resulting value is

[1+(R_F/R₁)][(R₊+R₃)/R₃]+(R_F/R₃).

In the simplest case, R₁ forms an open circuit, and ac noise gain equals

(R₊/R₃)+(R_F/R₃)+1.

Therefore, you can raise ac noise gain by using a low value for R₃ and a high value for R₊ and/or R_F.

The solution follows

For the particular case of a unity-gain follower, R_F is normally 0Ω as shown in Fig 3. According to the foregoing general analysis, if the value of R_S is low, ac noise gain is (R₄/R₅)+1, so you can increase ac noise gain—and therefore stability—by adding a large R₄ and a small R₅. (A large and constant R_S can make R₄ unnecessary; ac noise gain is then (R_S/R₅)+1.)

With LM110/LM310s, for example, 10k is an appropriate value for R₄. Using R₅ = 3.3k and C₅ = 200 pF, the LM110 stably drives capacitive loads up to 600 pF.

Technique speeds followers
You can also wire the resistor/capacitor combination across an op amp's inputs to increase the follower's slew rate. For example, an LF357 op amp's decompensation with a small internal capacitor normally requires gains higher than five to maintain stability (Fig 4). But the LF357 fits unity-gain-follower applications as easily as the LF356 (which is identical to the 357 except for the 356's internal compensation) and achieves better results. When source resistance is less than 1k, both the LF357 and 356 provide fast, stable responses, but the 357 has a 50V/μsec slew rate (typical) compared with 12V/μsec for a 356.

The LM349 decompensated quad op amp furnishes a bipolar input stage with a finite bias current (200 nA max). For best results in this application, add the resistor that controls the noise gain equally to the inverting and noninverting inputs as shown in Fig 5. With this circuit, the LM349 can slew at 2V/μsec typ and handles audio signals much faster—and without distortion—than the compensated LM348 (which, at 0.5V/μsec, slews only as fast as the general-purpose LM741). You can use the same approach for an LM101 by employing a 5-pF damping capacitor.

Watch for problems

While inserting a resistor/capacitor combination across the inputs gives faster slewing, the circuit's bandwidth could degrade if source impedance (R_S) increases. In addition to guarding against bandwidth problems, make sure ac noise doesn't reach an objectionable level when you raise ac noise gain. Although most modern op amps exhibit low noise, raising that noise gain to 10 can significantly increase output noise.

If the series capacitor across the op amp's inputs is larger than necessary for stability and high slew-rate purposes, noise increases unnecessarily. In general, choose the minimum capacitance for the circuit in Fig 3 according to the following formula (where f_V = op amp's unity-gain bandwidth):

C_5min = 4[1+(R₄/R_S)]/2πR₅f_V=(R₄+R₅)/(π/2)f_V(R₅)². To allow for tolerance variations, make C₅'s circuit value two or three times C_5min.

source: http://www.edn.com/article/518641-Improved_unity_gain_follower_delivers_fast_stable_response.php

Bootstrap Buffer Based Preamp

2011-07-07T04:42:00.000+07:00

I have been playing with a number of variations of the circuit as a free standing preamp, headphone amp, 321/729 replacements and as a potential active crossover, any and all of which may happen if there is demand. There has been strong interest in all of the threads and my bootstrap buffer preamp is up and running nicely - and for the moment it's staying. The same board should also be very handy as a headphone amp - & I'll be trying that next week.
They are different animals in so many different ways and come from completely different design philosophies. . and these are only my own observations and conclusions - so Jiim & PD feel free to chip in...please!

The starfish is definitely and very firmly in the Naim mold...and I love it for many things...lots of bass, drive and pace it really rocks..., but I can't help feeling that it's adding it's own signature to the sound. It's obviously based on maximizing the potential of the classic Naim 321 and 729 circuits and that means sorting a complex grounding scheme and multiple local regulators for power supply sensitive circuits. Accordingly it has a large and somewhat expensive BOM and is a fairly complex build.

The Bootstrap on the other hand is so much simpler and follows a minimalist design approach with as few components as possible in the signal path - it also uses symmetrical power rails and minimizes ground points in the signal path. So the BOM is smaller, the build easier and much more economical - I'll post a BOM in the next day or so. The result in the early listening is a cleaner sound with incredibly low noise and distortion, and I believe a much more truthful and honest presentation of the source material with uncanny staging and detail retrieval.

It's my expectation that I'll end up using both, the Starfish in a larger system (active Briks..) and mainly for rock & large scale orchestral music, the Boostrap in a smaller system where I'm looking for more space and precision, blues, jazz and acoustic programme material.

I guess that one of my conclusions is that just as no one system will please everyone, no one system is best for reproducing all types of material - at least not for my ears.

Schematics

Bootstrap Buffer Based Preamp

Bootstrap Buffer Based Preamp Single Rail Supply

Source:http://www.pinkfishmedia.net/forum/showthread.php?t=73412

TURBO: A series of bipolar transistor amplifiers

2011-07-07T04:18:00.001+07:00

25 Watt to 100 Watt, the range of TURBO is broad enough to satisfy everyone's needs.
These amplifiers are still valid and will satisfy lovers of the "bipolar" and those wishing to embark on the realization of a way "serious" quality.

In November 1980, Dominique JACOVOPOULOS published in Radio plans a series of bipolar amplifiers TURBO .

Here are excerpts:

* Amplifier TURBO 50

The amplifier TURBO 50, 50 Watt/8Ω

The article is available: http://cid-2e899d20263c980b.office.live.com/self.aspx/Public/Amplificateurs%20bipolaires%20TURBO/AMPLI%20TURBO%2050%20W%20.pdf

* Amplifier TURBO 75

The amplifier TURBO 75, 75 Watt/8Ω

The article is available:http://cid-2e899d20263c980b.office.live.com/self.aspx/Public/Amplificateurs%20bipolaires%20TURBO/TURBO75%20v2.pdf

* Power supply

This power supply is adjustable from 30 to 40V/3A and allows to connect the two channels of a TURBO 50 and TURBO 75.

The article is available:http://cid-2e899d20263c980b.office.live.com/self.aspx/Public/ARTICLES%20DJ/ALIM%20REGULE%20L146.pdf

* Amplifier TURBO 100

Turbo 100 output power 100 Watt/8Ω

In January 1981, published in Radio Plans # 398 the 100 Turbo.

The article is available:http://cid-2e899d20263c980b.office.live.com/self.aspx/Public/Amplificateurs%20bipolaires%20TURBO/AMPLI%20BIPOLAIRE%20TURBO%20100W.pdf

* Amplifier TURBO 25

TURBO amplifier 25 Watt/8Ω

The article is available:http://cid-2e899d20263c980b.office.live.com/self.aspx/Public/Amplificateurs%20bipolaires%20TURBO/ARTICLE%20AMPLI%20TURBO%20225%20DJ.pdf

TURBO 25 regulated power supply (polarity shown here)

Chemical charge a capacitor to smooth voltage at 100 Hz has too much work to undergo more random shocks for a long time. Its longevity depends greatly on operating conditions, performance related to them.
TURBO in the diet, the filter head C 1 assumes the thankless role.

But the sound is extracted from C6 is charged at constant voltage by the voltage stabilizer interposed between these two chemicals. Here we have a system with rapid transfer of energy under the control of the valve that is the electronic ballast transistor. This ensures the best performance in chemical output that does not suffer as current variations.

Extract from Article TURBO 25

Plans Radio 403, 06/1981

Radio coverage of the Plans No. 396.

source:http://amplifredy.wordpress.com/2009/03/04/amplificateurs-a-transistors-bipolaires-turbo/

50 watts transistor amplifier

2011-07-07T03:44:00.002+07:00

The amplifier and speakers that can handle medium-power is designed to provide a strictly amateur. Accidental overloads can damage the speakers, it is not appropriate for small systems.

What amp settings do not contain an element of the first connection wiring must be careful to work with.
Characteristics of the transistor, the fan or heat sink is cooled enough to find out if you need to focus!

Tech. parameters:
Power: + - 28V
Power: 50W / 4 ohms
Input sensitivity: 250mW of
Input resistance: 50 kOhm
Frequency range: 30Hz to - 30kHz

Optimal mobile recording portable player to another amplifier Multi Media.

Here, the schematics this power amplifier

List of components:
R1, R2, R9 - 56K
R3 - 3K3
R4, R6 - 100R
R5 - 220R
R7, R8 - 120R
R10 - 1K
R11 - 1R
C1 - in 1μF / 35V
C2 - 33P - Ceramics
C3 - the 100μF/35V
C4 - 100 N (220N) - Ceramic
C5, C6 - 4.7 UF / 35V
D1, D2 - 1N4007
T1, T2, T9 - BC546
Q3 - BC640
T4 - BD139
T5, T7 - BD711
T6 - BD140
T8 - BC639

Following the DC voltage amplifier and limiter speaker protection is needed.

source: http://www.volta.estranky.cz/clanky/zesilovace-a-predzesilovace/tranzistorovy_zesilovac_50_W.2.html

100 Watt Audio Power Amplifier

2010-11-13T14:28:00.008+07:00

This is an exceptionally well designed amplifier, with a lot of power reserve, high fidelity, low distortion, good S/N ratio, high sensitivity, low consumption and full protection. Having all these almost ideal characteristics this amplifier is likely to become the basic building block of your future high fidelity system, or it can also become the element that will upgrade your existing system.

How it Works

The circuit works from a symmetrical ñ 40 VDC power supply and draws a maximum current of 2.6 A. The input circuit of the amplifier is a differential amplifier built around Q4 and Q5 that employ DC feedback thus preventing any DC voltage from appearing across the speaker with the usual destructive results. Q11 acts as a current source and ensures that the input stage draws a constant current of 1 mA.

The signal which appears as a voltage drop across the resistor connected in series with the collector of Q4 is used to drive the DARLINGTON pair Q3, Q2 which together with the constant current source of 7 mA that is Q10, form the driver stage. This stage operates in class A and is driving the complementary output stage Q1, Q9. The transistor Q7 is used to balance the circuit at different temperatures and must be mounted on the heatsink between the out put transistors. The feedback loop which consists of R8, R9, C2, C3 provides AC stability to the circuit. The circuit also incorporates a protection stage that makes it virtually indestructible. This protection circuit is built around Q6, Q8. If for whatever reason the output remains connected on one supply rail and the common the output is also protected from high DC voltages that could burn the speakers. The supply rails should be protected by 2 A fuses for the 8 ohm version and 3 A for the 4 ohm.

Technical Specifications - Characteristics

Output power (f=1 KHz, d=0.5 %): 100 W in 8 ohm

Supply voltage: ................ 40 V

Quiescent current: ............. 50 mA

Maximum current: ............... 2.6 A

Sensitivity: . 600 mV

Frequency response: ............ 10-35000 Hz (-1 dB)

Distortion HD: ................. 0.01 %

Intermodulation dist.: ......... 0.02 %

Signal/noise: 83 dBConstruction

PLEASE READ THIS BEFORE YOU START CONSTRUCTION

To cater for those who wish to use 4 ohm speakers with this amplifier the Kit includes the necessary components for both versions. The components that differ are R3,4,17 and 23. If you build the 8 ohm version then you must also include in the circuit R28 and D7, D8 which are not used in the 4 ohm version. As you see all the components are already marked on the component side of the p.c. board.

The construction is made this way much simpler. Start the construction from the pins and the jumper connections, continue with the resistors and the capacitors and last solder in place the semiconductors. Check each resistor before soldering it, to see if its colours match those in the component list. Be careful with the electrolytic capacitors because their polarity should be respected. The polarity of those capacitors is marked on their bodies and on the component side of the p.c. board.

NOTE: On the p.c. board next to R2, R16 are marked two other resistors which do not appear in the circuit diagram but are included in the components. They are of 1 ohm 2 W (brown, black, gold) and must be included in the circuit. Take care when you are soldering the semiconductors because if you overheat them they can be damaged.

The output transistors should be mounted on the heatsink that is included in the kit. Take care not to short circuit them with the heatsink and we recommend that you use some HTC between the transistor body and the sink in order to improve heat dissipation. Follow the diagram for the mounting of the power transistors as it shows clearly how to insert the insulators and the screws. Q7 should be made to touch the heatsink and is a good idea to use a bit of HTC between its casing and the surface of the heatsink.

When you finish the construction of your project clean the board thoroughly with a solvent to remove all flux residues and make a careful visual inspection to make sure there are no mistakes, components missing and short circuits across adjacent tracks on the board. If everything is OK you can make the following connections: Input: 3 (signal), 5 (common) Output: 7 (signal), 6 (common) Supply: 1 (-40 VDC), 2 (+40 VDC) 5 (0 VDC)

Connect a milliammeter in series with the power supply, short the input of the amplifier, turn the power ON and adjust the trimmer P1 so that the quiescent current is about 50 mA. When you finish this adjustment remove the shunt from the input and connect the output of a preamplifier to it. Connect the pre amplifier to a suitable source and turn everything ON.

The signal should be heard from the speakers clear and undistorted. First of all let us consider a few basics in building electronic circuits on a printed circuit board. The board is made of a thin insulating

material clad with a thin layer of conductive copper that is shaped in such a way as to form the necessary conductors between the various components of the circuit. The use of a properly designed printed circuit board is very desirable as it speeds construction up considerably and reduces the possibility of making errors. Smart Kit boards also come pre-drilled and with the outline of the components and their identification printed on the component side to make construction easier. To protect the board during storage from oxidation and assure it gets to you in perfect condition the copper is tinned during manufacturing and covered with a special varnish that protects it from getting oxidised and makes soldering easier. Soldering the components to the board is the only way to build your circuit and from the way you do it depends greatly your success or failure. This work is not very difficult and if you stick to a few rules you should have no problems. The soldering iron that you use must be light and its power should not exceed the 25 Watts. The tip should be fine and must be kept clean at all times. For this purpose come very handy specially made sponges that are kept wet and from time to time you can wipe the hot tip on them to remove all the residues that tend to accumulate on it.

DO NOT file or sandpaper a dirty or worn out tip. If the tip cannot be cleaned, replace it. There are many different types of solder in the market and you should choose a good quality one that contains the necessary flux in its core, to assure a perfect joint every time.

DO NOT use soldering flux apart from that which is already included in your solder. Too much flux can cause many problems and is one of the main causes of circuit malfunction. If nevertheless you have to use extra flux, as it is the case when you have to tin copper wires, clean it very thoroughly after you finish your work. In order to solder a component correctly you should do the following:

Clean the component leads with a small piece of emery paper. - Bend them at the correct distance from the component body and insert the component in its place on the board.
You may find sometimes a component with heavier gauge leads than usual, that are too thick to enter in the holes of the p.c. board. In this case use a mini drill to enlarge the holes slightly. Do not make the holes too large as this is going to make soldering difficult afterwards.
Take the hot iron and place its tip on the component lead while holding the end of the solder wire at the point where the lead emerges from the board. The iron tip must touch the lead slightly above the p.c. board.
When the solder starts to melt and flow, wait till it covers evenly the area around the hole and the flux boils and gets out from underneath the solder. The whole operation should not take more than 5 seconds. Remove the iron and leave the solder to cool naturally without blowing on it or moving the component. If everything was done properly the surface of the joint must have a bright metallic finish and its edges should be smoothly ended on the component lead and the board track. If the solder looks dull, cracked, or has the shape of a blob then you have made a dry joint and you should remove the solder (with a pump, or a solder wick) and redo it.
Take care not to overheat the tracks as it is very easy to lift them from the board and break them.
When you are soldering a sensitive component it is good practice to hold the lead from the component side of the board with a pair of long-nose pliers to divert any heat that could possibly damage the component.
Make sure that you do not use more solder than it is necessary as you are running the risk of short-circuiting adjacent tracks on the board, especially if they are very close together.
When you finish your work cut off the excess of the component leads and clean the board thoroughly with a suitable solvent to remove all flux residues that still remain on it.

If it does not work

Check your work for possible dry joints, bridges across adjacent tracks or soldering flux residues that usually cause problems. Check again all the external connections to and from the circuit to see if there is a mistake there.

See that there are no components missing or inserted in the wrong places.

Make sure that all the polarised components have been soldered the right way round. - Make sure the supply has the correct voltage and is connected the right way round to your circuit.

Check your project for faulty or damaged components. If everything checks and your project still fails to work, please contact your retailer and the Smart Kit Service will repair it for you.

L1 : 10 turns with wire 0,5mm turned on a restistor of 1W

If you use a 4Ohm speaker you will place R3,4,17,23 at the board.

If you use a 8Ohm speaker you will place D7 D8 and R28.

For R2 and R16 if you don't find a 0,47Ohm place two of 1 Ohm parallel.

R16 must be 0,47Ohm...the 1Ohm must be a typographical error, take care of this, i haven't tested it.

Compact High-Performance 12V 20W Stereo Amplifier

2010-11-06T14:20:00.001+07:00

Amplifiers which run from 12V DC generally don’t put out much power and they are usually not hifi as well. But this little stereo amplifier ticks the power and low distortion boxes. With a 14.4V supply, it will deliver 20 watts per channel into 4-ohm loads at clipping while harmonic distortion at lower power levels is typically less than 0.03%.

This is an ideal project for anyone wanting a compact stereo amplifier that can run from a 12V battery. It could be just the ticket for buskers who want a small but gutsy amplifier which will run from an SLA battery or it could used anywhere that 12V DC is available – in cars, recreational vehicles, remote houses with 12V DC power or where ever.

20W Stereo Audio Amplifier

Because it runs from DC, it will be an ideal beginner’s or schoolie’s project, with no 240VAC power supply to worry about. You can run it from a 12V battery or a DC plugpack. But while it may be compact and simple to build, there is no need to apologise for “just average” performance. In listening tests from a range of compact discs, we were very impressed with the sound quality.

Long-time readers might recall that we presented a similar 12V power amplifier design back in May 2001. It was a similar configuration to this one but it is now completely over-shadowed by the much lower distortion and greatly improved signal-to-noise ratio of this new design. In fact, let’s be honest: the previous unit is not a patch on this new design. It used two TDA1519A ICs which resulted in distortion figures above 1% virtually across the board and a signal-to-noise ratio of only -69dB unweighted.

20W Stereo Amplifier Circuit

However, by using the TDA7377 power amplifier IC and making some other improvements, the THD (total harmonic distortion) of the new design is about 50 times better than the older unit (see performance graphs for details). The bottom line is that the THD under typical conditions is around just 0.03% or less. It is also able to deliver more output power due to the improved output transistors in the new power amplifier IC.

In addition, its idle power consumption is low – not much more than 1W. As a result, if you don’t push it too hard it will run cool and won’t drain the battery too quickly. And because the IC has self-protection circuitry, it’s just about indestructible. It will self-limit or shut down if it overheats and the outputs are deactivated if they are shorted.

Circuit diagram:

20W Stereo Amplifier Circuit Diagram

With a 12V supply, the largest voltage swing a conventional solid-state power amplifier can generate is ±6V. This results in a meagre 4.5W RMS into 4O and 2.25W RMS into 8O, without considering losses in the output transistors. Even if the DC supply is around 14.4V (the maximum that can normally be expected from a 12V car battery), that only brings the power figures up to 6.48W and 3.24W for 4O and 8O loads respectively – still not really enough.

There are three common solutions to this problem. The first is to boost the supply voltage using a switchmode DC converter. This greatly increases the cost and complexity of the amplifier but it is one way of getting a lot of power from a 12V supply. However, we wanted to keep this project simple and that rules out this technique.

Parts layout:

There are variations on the boosting method, such as the class H architecture used in the TDA1562Q IC featured in the Portapal PA Amplifier (SILICON CHIP, February 2003). It is able to achieve 40W/channel but with >0.1% THD. In that case, the amplifier output itself provides the switching for a charge pump. The second method is to lower the speaker impedance. Some car speakers have an impedance as low as 2O, which allows twice as much power to be delivered at the same supply voltage. However, we don’t want to restrict this amplifier to 2O loudspeakers.

Author: Nicholas Vinen - Copyright: Silicon Chip

Identify IC TDA7293 and TDA7294 Fake or Original

2010-11-04T09:29:00.001+07:00

TDA7293 and TDA7294 is a common feature of the bootstrap capacitor is not installed work as usual, which gives an opportunity for unscrupulous traders to provide fake, counterfeit goods market is the most polished printed for the TDA7294 TDA7293, from the printing on the can identify, find a few different batches of IC for your reference:

If you can not see it, multimeter test:

TDA7294 pin 11, pin 12 empty legs, open state is insulated

TDA7293 pin 11 (voltage amplification stage output), pin 12 (bootstrap) has a resistance:

Picture this subject as follows: 3456 +1. Gif

TDA7293 limit voltage 120v

Limit voltage 100v TDA7294

I found that some batches were TDA7294 90V breakdown in the type of IC sound like TDA2030, reaction was slow, boring sound, though not sure whether the fake, but certainly not a good thing!

The breakdown is not more than 90V, the general performance of the midrange and treble sound clear and bright, fast response! Found in different batches of test and origin of the TDA7294 sound even different!

Sound quality not as good as Legend TDA7293 TDA7294, wrong! I found a few pieces of genuine TDA7293 sample tests and found TDA7293 TDA7294 sound much better than that, the biggest feature is bright! Fast! Power foot.

Above are for reference only, are welcome to share and talk about their experiences

TDA7293 + upc1237 Integrated Amplifier with Speaker Protection Circuit

2010-11-03T09:23:00.001+07:00

TDA7293 + upc1237 integrated amplifier speaker protection circuit board,with Morocco genuine IC, clear and transparent sound quality!

Tao Bao link:http://item.taobao.com/auction/item_detail-0db1-244881dd32b6994bf95a150a8788fa2f.htm

Audio channel, "European "style, all with Philips capacitors:decoupling filtering using Philips C 470uf/50v audio capacitors, Philips 0.1uf, 100V MKT, input capacitance Philips 1uf/250V MKP (better than MKT ! less waste!) bootstrap capacitor: PhilipsPHILIPS22uf/100V audio capacitor, negative feedback DC blocking capacitors Philips 22uf/100V, full-bridge 25A1000V (15A is sufficient), filter capacitor 12000uF 2 only (measured). Coupling, bootstrap, negative feedback DC-blocking capacitors were installed before the match, reduced errors, more accurate positioning to pan!

Circuit real materials, design science will have good sound, small volume whenthe soft and delicatetenderness allows you to enjoy a "European style"! Alt bursting bright when you'll likely getloud!

The author of the test machine Speaker:http://item.taobao.com/auction/item_detail-0db1-709b9f1bc93a9fd146e0a994c2ad5026.htm

Circuit design features:

1:relay protection circuit can not be omitted!A speaker a few hundred dollars, and an IC tens of dollars!Switch which is no current impact sound amplifier fever minimum requirement!

2: Integrated rectifier, horn protection, power amplifier into one, convenient!

3: The filter capacitor is measured using instruments elected, the board adopted Sanyoung12000UF50WV, all of the measured capacity is greater than 10000uF, to ensure bursting with power! (Lot of brands on the market are sets of skin capacitance, renovation, disassemble parts, simply by the instrument that pays top academics ... a lot of testing capacity is only half! Filter capacitor also instruments speak for themselves!)

4: Audio channel system used in Europe and Philips MKT Philips electrolytic capacitor decoupling, resolving power better! The protection circuit uses Japanese-made capacitors do not waste resources and

5:1% of the audio channels all use metal film resistors;input capacitance with MKP. The face of hundreds of high-power operational amplifier K resistance, input capacitance, although little effect on MKP psychological effect or to vote for it!

6: The most critical is the choice of high-power amplifier TDA7293IC, you may not believe that a model with the quality of different batches of the IC 369 will be divided and so on, but I tested a few batches of the TDA7293, even sound different! In order not to touch the interests of some business, do not say. OUR engineer "winnowed out" some good batches of IC on Taobao only for your reference!

TDA7293IC URL:http://item.taobao.com/auction/item_detail-0db1-79629e1471dbd6e18c2d260b9daf3228.htm

Recognition of experience TDA7293/7294 Post:http://www.avtech.cn/dispbbs.asp?boardid=4&Id=418

Is limited, I hope you valuable advice!

TDA7293ICbasic parameters:

Power: 140W +140 W

Output Impedance :4-8 ohms

Harmonic Distortion: 0.005%

Input voltage :24-30V dual AC input (recommended).

Board body size: 14 X 7.8 X 6 dimensions (cm)

Note: IC such as TDA7293 or TDA7294 heat sink and the negative power of its similarities to install the radiator and IC must be isolated from insulation, thermal conductivity recommended mica and particles, buying power amplifier board shop and complimentary high-quality mica particles

Hi-Fi Integrated Circuit (IC)Power Amplifier Application

2010-11-02T09:18:00.000+07:00

Common market Hi-Fi integrated circuit (IC) power amplifier, mainly the following three products:

National Semiconductor Corporation (NSC), on behalf of products LM1875, LM1876, LM3876, LM3886, LM4766 and so on.
Dutch Philips (PHILIPS), on behalf of products TDA15×× series, the more well-known is the TDA1514 and TDA1521.
Italian - French Microelectronics (SGS), the more famous is TDA20×× series and DMOS tube TDA7294, TDA7295, TDA7296. NSC warm neutral tones the company's products, Philips is more bright and delicate products.

Integrated Circuit (IC) power amplifier heat sink comes with two types of insulated and non insulated. Insulation class, such as the LM series suffix TF varieties, the overall molding process, simply fixed directly to manifold and radiator. Most of the exposed metal heat sink integrated amplifier is a non-insulated type, the heat sink generally negative supply connected, not to use its contacts with other parts of the amplifier (especially the case with the ground), otherwise the damage immediately Manifold.

I found that by comparison, non-insulated block of the thermal resistance of the lower class of power amplifier output power to be slightly larger.

On the circuit in the form of choice, I think that, with the manufacturer to the voltage feedback circuit, and were also given on the basis of indicators to test out, since the recommendation, the circuit should be able to play better the performance of integrated block, the actual is also true. Current feedback and DC servo amplifier is an integrated application of a useful attempt, but the results should not be overstated.

DC voltage should not get too high, or only Manifold serious fever, and the sound quality deterioration, and may lead to over-voltage protection circuit malfunction. Should give priority to the use of manufacturers recommended voltage, if not, can be the limit × 85% voltage DC voltage, then divided by the DC voltage AC voltage was 1.25.

Amplifier without the use of power supply, but the power of the power capacity must be adequate. Desirable power transformer twice the total output power, and well shielded. Rectifier to choose low internal resistance, and both ends of each tube and on a small capacitor. Filter capacitance Enough is enough, do not blindly seek large, can be calculated per 10W 2200μF. If funded, with the transformer more effective.

Integrated amplifier with external components small, quality product should be selected. Coupling capacitor MKP better not to use electrolysis, the larger-capacity tantalum electrolytic bypass capacitors can be used, use a small capacitor CBB or MKP. To make use of rings of metal film resistors or Holco resistor, and power can not be less than 1/4W, 1/2W the conditional use. In the installed components should be checked before and pay attention to the error and the pair of. Do not blindly imported supplements, supplements, low cost components Moreover, many fakes.

Amplifier circuit layout should follow three principles:

Point grounding. Integrated circuit, the input, the output filter capacitor to have a separate receipt to the "point", do not any overlap, to avoid the introduction of noise.
Size of the signal separation. The input signal should stay away from the output signal and power, the specific design printed board, there are two ways, one is a single signal flow method, the printing plates from one end of the input signal, the other end of the output; the other is ground isolation method that the size of the signal isolation between the land line.
Transmission mask. Small-signal transmission lines must use shielded cable, and single-grounded shield. Other aspects, such as symmetrical layout of components, increase the ground area and increased width of high-current copper foil (or even on the tin, etc.) are also beneficial to reduce the noise. Isolated input inductor can be installed, the output inductor installed damper

As today's digital audio output voltage swing is sufficient to achieve most of the integrated amplifier's input sensitivity, so the application just before a buffer stage, volume control and sound deployment of the role. There are two types commonly used in the first stage, one is before the op amp-type level, the higher its index, the sound quality is better, but must use high-quality potentiometers; the other is constituted by a dedicated integrated circuit before the tone volume level, such as LM1036, LM4610, TDA1524, etc., they are low cost, simple and easy system to use does not affect the sound quality of ordinary potentiometer, and the results satisfactory, fans can choose according to the actual situation.

Today, various types of integrated amplifiers have adopted the relevant protection measures, by contrast, NSC's LM series should improve some, but not foolproof, especially for the protection of fragile speakers. So, if you use more expensive speakers, I still recommend installing speaker protection and good Power Supply component.

PT2399 Echo, Reverb Effects Schematic Circuit

2010-11-02T08:50:00.000+07:00

Brief Description:

IC PT2399 from Princeton Technology Corporation. Pin 15 and pin 16 to form a capacitance by changing the external resistance to change the input frequency response of the inverting amplifier, as the signal input. Pin 8, pin 9, pin 10 form an external pre-emphasis - Compare the source set, the internal microcontroller output DO0 after passing through the circuit compared with the input signal, thus completing the A / D conversion, and then 1bit of data into the microcontroller the Delay Line.

Similarly, pin 11, pin 12 and pin 7 form to add - Compare source circuit, the signal from pin 12 out. And pin 13 , pin 14 is a separate inverting amplifier, and not directly connected with the internal processing circuitry, it can be used flexibly for the designers.

Pin 6 to control the speed of the internal MCU Delay Line VCO input, changing the voltage can change the delay time, and from pin 5 to monitor the current oscillation frequency. Pin 2 for the internal op amp reference when a single supply source, the integrated circuit is well within 1/2 partial supply voltage, so only the external access to anti-ripple circuit (voltage regulator) to.

PT2399 frequency response within the limits of about 5kHz, and when the input signal when the frequency is higher than 4kHz, sine wave input signal will become somewhat similar to the triangle wave, and in the input signal frequency is greater than 5kHz, it will produce distortion and digital noise.

Although the guitar signal in the above information on this range is relatively small, but the delay of the chip to deal with these frequency response will be smooth and some distortion.

PT2399 input signal amplitude is about 3Vpp signal level higher than this range will be limiting. In the above diagram, the change of pin 15, pin 16 of the resistive and capacitive components, you can change the input frequency response; change components on pin 12 , pin 13, pin 14 of the resistive and capacitive components, you can change the output frequency response.

The internal structure of integrated circuits based on PT2399, the two parts of the design is the operational amplifier filter design, designers can calculate the actual situation, to not repeat them here.

In addition, PT2399 VCO external setting resistors to the minimum, the delay time is 31.3ms, because of this a long time, not suitable for production of chorus or Flanger effects.

For more future information about IC PT2399

Source : http://http://www.avtech.cn/dv_rss.asp?s=xhtml&boardid=4&id=64&page=2

Echo Application Schematic Circuit

Guitar Effect Application Schematic Circuit

Bottom Layout of PCB

Component Layout of PCB

Stereo Audio Power Amplifier 11 Watt using LM4752

2010-10-25T16:27:00.002+07:00

Featuring drives 4 Ohm and 8 Ohm loads, single supply operation, compact 7-lead TO-220 package, wide supply range 9V – 40V, internal thermal protection, internal gain resistors (AV = 34 dB), the LM4752 is a stereo audio application circuit of Stereo Audio Power Amplifier 11Watt using LM4752. amplifier capable of delivering 11 Watt per channel of continuous average output power to a 4 Ohm load, or 7 Watt per channel into 8 Ohm using a single 24V supply at 10% THD+N. This stereo audio amplifier is applied mostly in multimedia speakers, stereo TVs, Mini component stereos, and compact stereos.

schemtic digram circuit of Stereo Audio Power Amplifier 11 Watt using LM4752

The following article (well actually datasheet) contains detail information about LM4752 Stereo Audio Power Amplifier 11 Watt description, illustration, schematics and circuit diagrams, specification, key features, application, connection diagrams, absolute maximum ratings, operating ratings, electrical characteristics, test circuit, equivalent schematic diagram, system application circuit, external components description, typical performance characteristics and physical dimension. Here is a quotation from the LM4752 datasheet:

“Proper PC board layout is essential for good circuit performance. When laying out a PC board for an audio power amplifier, particular attention must be paid to the routing of the output signal ground returns relative to the input signal and bias capacitor grounds. To prevent any ground loops, the ground returns for the output signals should be routed separately and brought together at the supply ground.”

Find more about Stereo Audio Power Amplifier 11 Watt using LM4752 here – 22 pages of PDF filetype. (source: national.com). Find also other Audio Amplifier application you might be looking for.

External link:

LM4752 Stereo Audio Power Amplifier 11 Watt Datasheet – www.national.com

author: Wiring Diagram
e-mail:
web site: http://www.wiringdiagrams21.com/

10 Watt Audio Power Amplifier with Bass-boost

2010-10-15T16:23:00.000+07:00

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 100uF 25V Electrolytic Capacitors
C3,C4 470uF 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 4700uF 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

schematic/circuit diagram

schematic diagram circuit of 10 Watt Audio Power Amplifier with Bass-boost

Comments:

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 or TL072 for Excellent sound use ic OPA2134 Dual IC but, obviously, its power output will be comprised in the 9.5 - 11.5W range, as the supply rails cannot exceed ±18V.

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 ensures a more linear regulation of bass-boost.
Don't 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 in the same point the ground sides of J1, P1, C2, C3 &C4. Connect C9 at the output ground.
Then connect separately the input and output grounds at the power supply ground.

Technical data:
Output power: 10 Watt RMS @ 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

author: RED Free Circuit Designs
e-mail:
web site: http://www.redcircuits.com/

TDA1566 Car Audio Power Ampliﬁer

2010-09-22T04:50:00.002+07:00

The TDA1566 is a car audio power ampliﬁer with a complementary output stage realized in BCDMOS. The TDA1566 has two Bridge Tied Load (BTL) output stages.
The TDA1566 can be conﬁgured in a single BTL mode and drive a 1 Ω load. For the single BTL mode it is necessary to connect on the Printed-Circuit Board (PCB) the outputs of both BTL channels in parallel.

The TDA1566 is a car audio power ampliﬁer, whose schemematic is shown below, built on a model schemematic include chips TDA1566. The TDA1566 is a car audio power ampliﬁer does not require the establishment and therefore suitable for repetition, even beginners.
In a unipolar power load (speaker system) includes a bridge circuit which does not require the separation of electrolytic capacitors of high capacity.

Schematic TDA1566 Car audio power amplifier

At a load resistance of 4 ohms and power voltage 14,4 Volt chip developed 2X23 Watt's, and at a load of 2 ohms - 2x40 Watt's. Tues Rejection Ratio ripple voltage 70 dB, frequency response at the level of -1 dB 20 Hz ... 20 kHz, the gain 26 dB, the level of intrinsic noise of -100 dBA.

The developed diagnostic system provides protection against overcurrent and overheating with indicator LED CLIP restrictions and protection operation LED DIAG. Mute and standby modes are included, respectively,
intermediate (from 2,5 to 4,5 V) and zero levels at the control input EN and connector STBY.

Download DataSheet clik here
skema power amplifier, high power amplifier schematic, power amplifier circuit, power amplifier schematics, power amplifier schematic, amplifier circuit diagram, rangkaian amplifier, skema amplifier, schematic diagram power amplifier, high power amplifier circuit diagram, TDA1566

Class H Power Amplifier TDA1562Q

2010-08-26T13:10:00.000+07:00

Several years ago we often hear class of power amplifier. We can make power amplifier in class A, class B or class AB.

Class H Power Amplifier

Class H power amplifiers take the idea of Class G one step further creating an infinitely variable supply rail. This is done by modulating the supply rails so that the rails are only a few volts larger than the output signal at any given time. The output stage operates at its maximum efficiency all the time. Switched-mode power supplies can be used to create the tracking rails. Significant efficiency gains can be achieved but with the drawback of more complicated supply design and reduced THD performance.

IC TDA1562Q is Class H Power Amplifier. Learn more about chip TDA1562Q can be found here.

Schematic diagram of the power amplifier TDA1562Q is shown in Figure 1, the appearance in Figure 2. Has an internal booster circuit elements that allow to develop at 4 Ohm load with power supply 14.2 volts, the power to 70 Watts

Fig.1 Schematic of TDA1562Q Class H Power Amplifier.

Fig.2 Kit of TDA1562Q Class H Power Amplifier.

There should be a reservation - this musical power, and no noise, which usually indicate a modern car audio equipment. Mainly on the presence of these parameters is that when measuring the noise power as a test signal using a rectangular audio signal. Of course, that under this test, power output is possible, but to call it music, hardly anyone turns language.

If the test checks power amplifier TDA1562Q on the noise power in the load 4 Ohm chip developed at the output of 130 watts, which is quite clearly shows that it is much more powerful than the chips used in stereo systems.
As is evident from all the above on the basis of this amplifier can be built quite compact size car for powerful acoustics, and for the sub-woofer. It is not necessary to assemble a fairly labor-intensive converters. Of course the amplifier nonlinear distortion based on the TDA1562Q is slightly higher than the amplifier with transformer-based TDA7294 or TDA7293, but it is still far less than many cheap car amplifiers priced up to $ 150.

Very Simply 10 Watts Stereo Power Amplifier-TDA2009A

2009-11-24T10:13:00.002+07:00

Here are a power amplifier with TDA2009A integrated circuits produced by 10 +10 W stereo amplifier (see figure). As a result of ASIC, making her the production becomes very simple, the performance is not bad.

Her main performance characteristics in the table below.

Power Supply Voltage: DC 8-24V/1-2A
Power Output:

10W RMS / channel, 4 ohm load, 24V/DC power;
6W RMS / channel, 8 ohm load, 24V/DC power;
4W RMS / channel, 4 ohm load, 12V/DC power.

S/N: >75dB/10W output
Frequency response: 10Hz-50kHz,-3dB
Gain: 36dB
Input Level: 100mV Full output power

Schematic and Prototype:

Principle and production elements:

C1, C2 as the input capacitor, C10, C11 for the output capacitor. C6, C7 for the feedback capacitance. R1/R2, or (R3/R4) control the amount of feedback. Amplifier gain is equal to 1 + (R1/R2) = 68, or 37dB. C4, C5 for the power supply filter capacitor. The device maximum supply voltage of 28V. Hours of work required to add TDA2009A heat sink, and should pay attention to the power lines and then the choice of speaker wiring. Input should use shielded lines and as short as possible. Welding TDA200A not take too long when you pay attention, action to be fast, but if you want their full integration with the circuit board.

Mini Subwoofer 5″ – 6″ BandPass 4th Order Isobaric

2009-11-11T02:43:00.002+07:00

The order of 4 or sealed rear chamber bandpass system is essentially a system of watertight enclosures with the addition of an acoustic filter for the driver. The resulting system usually provides a lower cut-off frequency, the compromise that a larger case. The space can be reduced by two drivers in isobaric configuration.

4th-order bandpass systems generally show better able to handle the functions that the other major systems are considered. The transient response and is second only to the sealed enclosure systems, making it a good choice for subwoofer applications.

Since all output 4th order bandpass system is via the port, the largest diameter possible for the port area should be used to minimize noise from the port. The ports must be incinerated where possible, for the same reasons.

4th order Ssobaric Subwoofer Box Design

The 4th order bandpass system rarely allows a perfect bandpass response - there is usually an out-of-band noise present in the production. A notch filter can be used simply to reduce the noise as audible. Otherwise, a lowpass filter used in series with the driver, but the in-band response system may be affected if this approach is taken.

As the speaker sound 4th order band pass issued by the openings or ports on the port side of the box, the port noise inevitable.

This unwanted noise can be minimized by a notch filter and the largest diameter possible for the port of the area should definitely be used. Another option is to burn the ports of the 4th order bandpass room as this will certainly help to reduce unwanted extra from the subwoofer.

Mini SubWoofer Power Amplifier clik for detail

WOOFER / MID MODEL - 5MP60 / N

Specifications
Nominal Basket Diameter 5 "/ 125mm
Impedance 8 ohm
RMS Power 50 Watts
Program Power 100 Watts
Frequency response 50Hz - 12.0kHz
Sensitivity (1W/1m) 91dB
Voice Coil Diameter 1 "/ 25.8mm
BL Factor 6.4 N / A
Voice Coil Length 14 mm
Air Gap Height 6mm
X Damage (peak to peak) 20 mm
Magnetic Assembly Weight 2.2 lbs / 1.0 kg.
Edit Information
Diameter 5.28 "/ 134mm x 5.28" / 134mm
Bolt Circle Diameter 5.4 "/ 137mm
Baffle Cutout Diameter --
- Front Mount 4.72 "/ 120mm
Many of the 4 mounting holes
Volume displaced by driver, 019 m 3 / .5 liter
Total Depth 2.68 "/ 68mm
Net weight 2.64 lbs / 1.2 kg.
Weight 2.8 lbs / 1.27 kg.
Materials
Basketball aluminum diecast
Polypropylene cone
Rubber Surround
Voice Coil Wire Copper
Ferrite
Thiele-Small Parameters
Resonance Frequency (FS) 60 Hz
Impedance (Re) 5.33 ohms
Coil Inductance (Le) 0.4 mH
Mechanical Q (Qms) 1.604
Electrical Factor (Qes) .35
Total Q (Qts) .29
Comp. Equivalent Vol. (Vas) 35 FT3 / 9.8 Liter
Voice Coil Overhang (Xmax) 4.0mm
Reference yield 5%
Volume Displacement 34 cm3

22 Watts Mini Subwoofer Circuit TDA1516 with Adjustable Frequency

2009-11-11T01:48:00.000+07:00

The subwoofer is a subwoofer or a speaker to reproduce low frequencies, devotee of 20 Hz to 150 Hz electronic circuit diagram below shows the details of a scheme of the main amplifier TDA1516 22 watt in 4 ohm car subwoofer driver. This device is designed for an existing stereo amplifier, often requires adding another blow to the music of driving a subwoofer.

The amplifier uses BTL is a good and cheap ((Bridge Tied Load channels) 13-pin IC TDA1516 from Philips is now NXP Semiconductors), which may provide a small number of components and 22W at 4 ohm load voltage 12 volt car battery default.

The device consists of several parts: the name of the potentiometer, dual-linear motion potentiometers, 1/4W resistors, capacitors, electrolytic 25V, 63V Polyester capacitors, LED, 100 mA NPN transistor, dual BIFET Op-Amp, 24 W BTL car radio RCA audio input amplifier and two speakers 4 ohm or 8 ohm woofers in isobaric parallel wiring.

DIY 12 volt car project Subwoofer frequency low-pass filter circuit and BTL Amplifier TDA1516

The signals from the line outputs for stereo mixing amplifier input drive, and taking into account the level of the signal to the buffer and can be reversed IC1A phase SW1. Such control may be useful to the subwoofer in phase with the speaker of the existing car radio.

Then, a variable frequency 12dB/octave-pass low IC1B, the components of the Q1 and then you can pass the low frequency of 70 Hz or 150 Q2, R17 and C9 form a voltage stabilizer to facilitate access and filtering circuit to prevent track of the services given power at a low level positive.

LPF subwoofer and amplifier parts list:

Potentiometer
P1-10K
P2-22K

Resistor
R1, R4-1K
R2, R3, R5, R6-10K
R7, R8-100K
R9, R10, R13-47K
R11, R12-15K
R14, R15, R17-47K
R16 6K8
R18-1K5

Capacitor
C1, C2, C3, C6-4μ7 25V
C4, C5-68NF 63V
C7 33nF 63V
C8, C9 220μF 25V
C10 470nF 63V
C11 100nF 63V
C12 2200uF 25V

Diode
D1 LED Lamp

Transistor
Q1, Q2 BC547

IC
IC1-TL072 Op-Amp
IC2-TDA1516BQ Car Amplifier 24 Watt BTL

Switch
SW1-Toggle SPDT
SW2-Toggle SPDT

RCA Jack
J1, J2 RCA Audio Input

SubWoofer Drive Unit
4-ohm woofer driver or two 8 ohm woofers connected to Isobaric

Isobaric 4th order Bandpass Subwoofer Box Design

2009-11-11T00:18:00.000+07:00

The fact that we need a subwoofer means that something is missing in the performance of the main speakers. This is not surprising, since the speakers unfortunately have to coexist with families, women and companions, leading to the inevitable Compact, stand-mounted speaker. Modern, compact speakers are excellent performances, but there is no further away from the laws of physics, small box = bad bass. So, modern speakers designed for a response in the low-limit?

User isobaric subwoofer on the Altec Lansing FX4021 and FX5051

4th isobaric subwoofer box design

The subwoofer is a bit of a word misnomer. It includes sub-audio course can not hear you. We mean really low sound. This does not mean we can not "collect" the sub-audio frequencies. The body can not perform under the form of audio-frequency vibrations and can strengthen the reality of the listening experience. There is usually little more low audio below 20Hz in most of the music.

The only (not electronic), an instrument can produce something in this Church is the body 16.67Hz. Even if this body is equipped with the solid pipe is usually filled with something to prevent the building collapsing around!

For practical reasons we can arrange to 20Hz as the lowest audio frequency that we want to reproduce, may be less than that, the boxes are often quite large. OK. So who determines the lowest frequency we want the subwoofer to handle, but what about the highest frequency?
It is easy to match the response of the existing speakers.

In my case, my speakers are-3dB at 47Hz. That is a lot better than most small speakers, 70-80Hz at-3dB is fairly typical. Ideally the subwoofer to be on the same-3dB frequency. It is easy acheivable a low-pass electronic filter. These can easily be made adjustable to fit almost all existing stakeholders.

Why only one subwoofer, we have two for stereo? The answer to this depends on how the human ear perceives direction. The brains very carefully compares the phase of sounds in the left ear or right and take a decision on this basis.

At high frequencies, the distance between the ears is an important part of the wavelength and the phase difference is large. Because the frequency is reduced, the distance between the ears small compared to the wavelength.

The phase difference is reduced making it difficult for the brains towards the sound calculates. It is not by any means the whole story, the ears also use the level difference and the slight head movements to better determine the direction. Below 200Hz, the human auditory system is almost fully able to determine direction, so it does not matter if the bass is in stereo, mono or even in the room where it originated.

Thus, a subwoofer is all you need. It is normal that the sum of the left and right channels within the subwoofer, so no information is lost. Joint Stereo is often used in the MP3 coding scheme. The low frequencies are encoded in mono, stereo at higher frequencies.

I have several cheap 180 mm / 6.5 "drives and carefully measured their parameters. This step is crucial in this kind of design that even small errors affect the frequency response drastically.

I used my speaker WinISD and added to the database to track the response and the size of the box to calculate. Compromises are necessary in this kind of design. You can find a good performance and a very narrow bandwidth or poor performance and a wider bandwidth. What is acheivable entirely dependent on the properties of the drive. I was fortunate in that my 3 pounds produced a pilot-3dB bandwidth of 29-76Hz. I can not change, but I could filter out the high-end to match my existing speakers.

I decided to use a configuration with two drive Isobaric back to back. This has the advantage of reducing by half the required volume of the two halves of the bandpass enclosure.

One effect of the tax Isobaric half volumes needed in contrast to cases where a driver was used. Another is that the port setting remains the same, but half of the volume, equivalent to a doubling of the port.

Note in the above table, the port is 401mm long. There is no place for him in the cavity 11 liter before with a little thought Latteral was necessary for the host. Some ideas are not at this point if the port can not be physically made to adapt. In this example, I solved this problem with the design.

Subwoofer Box Spec:

Number of cores 2 (used as an installation isobaric) 4th Order Bandpass Box Type Box dimensions for chamber 11.0 liters 24.5 liters Achterhuis Port tuning frequency of 46.56 Hz Wind 1 Wind -> Front Room from 0401 to 0060 m long x 0.060 m square

Power Amplifier Gainclones more Gainclones Power Amplifier

2009-10-25T04:05:00.000+07:00

2x25 Watt LM1875 Gainclone Amplifier

2x50W LM3875 Gainclone Amplifier

2x56W LM3876 Gainclone Amplifier

2x68W LM3886 Gainclone Amplifier

2x50W Tube Gainclone Hybrid Amplifier

Build Power Amplifier LM3876, Simply and Powerfull Power Amplifier

2009-10-25T03:25:00.000+07:00

The chip on which the amplifier is based, a Type LM3876, is a member of the Overture family from National Semiconductor, All members of this family are pin-compatible and mutually interchangeable. They are typified by an internal protection (called SPIKE). In practice, the diftection ference between them is the power output. The series was described on the basis of the LM3886 in an earlier issue*.

The PCB has been designed so what it can accommodate the LM3876 (50W) as well as the LM3886 (150W). Because of this, pin5 of the IC on the board is connected to the positive supply line. This connection is not needed for the LM3876, since its pin5 is not (internally) connected (NC).

The IC is located at the side of the board to facilitate fitting it to a heat sink as shown in the photograph.

An important aspect for optimum performance is the decoupling of the unregulated supply lines by C 7-10. All earth connections go to a single terminal on the board.

Air-cored inductor L1 consists of 13 turns of 1mm dia. enamelled copper wire with an inner diameter of 10mm. The completed inductor is pushed over R7 and its terminals soldered to those of the resistor.

All electrolytic capacitors must be mounted upright. The amplifier can be muted with a single-pole switch connected to the MUTE input (pin8). This function is enabled when the switch is open. If muting is not required, solder a wire bridge across the mute terminals on the board.

Boucherot network R6-C6 is not normally required in this application, but provision has been made for it for use in other applications.

According to the manufacturers, both chips are optimalized for a load of 8 Ohm. The output power is lower when a 4 Ohm load is used or when the supply voltage is reduced. When a 4 Ohm load is used, the SPIKE protection becomes active when the supply voltage is about 27V, resulting a in a reduction of the power output to 10W. This means that it is not advisable to use loudspeaker with an impedance < 8 Ohm.

For best result you can expand power amplifier using BPA-200 Amplifier

Part list

Resistor:
R1, R3 = 1 k
R2, R4, R5 = 18k
R6 = see text
R7 = 10R, 5 Watt
R8, R9 = 22k

Capacitors:
C1 = 2.2 uF
C2 = 220 uF, 160 V
C3 = 22 uF, 40 V
C4 = 47 pF
C5 = 100 uF, 40 V
C6 = see text
C7, C8 = 100 nF
C9, C10 = 1000 uF, 40 V

Inductors:
L1 = 0.7 uH - see text

Integrated circuits:
IC1 = LM3876T

Miscellaneous:
Heat sink for IC1 < 1.5 K W-1
Single-pole switch - see text

Schematic and PCB Layout LM3876

Build Power Amplifier LM4780 with BPA-200 Amplifier

2009-10-24T01:36:00.000+07:00

This is design is very similar to the National Semiconductor BPA-200 (Bridge/Parallel Amplifier) which uses 4x LM3886 per channel and an input buffer:

Nothing Special in design but usefully for more watts!
My one will use 2x BrianGT LM4780 kits and a balanced line driver to bridge them, like this:

The LM4780 is a stereo audio amplifier capable of typically delivering 60W per channel of continuous average output power into an 8 load with less than 0.5% THD+N from 20Hz - 20kHz.
The LM4780 is fully protected utilizing National's Self Peak Instantaneous Temperature (°Ke) (SPiKe^TM) protection circuitry. SPiKe provides a dynamically optimized Safe Operating Area (SOA). SPiKe protection completely safeguards the LM4780's outputs against over-voltage, under-voltage, overloads, shorts to the supplies or GND, thermal runaway and instantaneous temperature peaks. The advanced protection features of the LM4780 places it in a class above discrete and hybrid amplifiers.

Each amplifier of the LM4780 has an independent smooth transition fade-in/out mute.
The LM4780 can easily be configured for bridge or parallel operation for 120W mono solutions.

The total effect is (2x LM3886's paralleled) x2 Bridged and should give approx 225 watts into 8 ohm and 335 watts into 4 ohm when used with a sufficient power supply.

The line driver part is based on the DRV134 and a PCB from digi01, you can see the details here.

In the end mine was dual mono in a recycled amp case using 2x 300VA (18VACx2) toroidal transformers, 54,400uF of capacitance per channel with a snubber. The DRV134s add 6dB of gain so I set the LM4780s to about 16x gain to compensate (they are set to 33 normally). I get no DC offset, no hum, no crackle or thump on turn on or turn off, silent as.

Pics.....

DIY Cat5 Speaker Cables

2009-10-06T08:44:00.000+07:00

These are perfect speaker cables for my brother speaker. I build use AMP Cat6 cables, for detail view here.

AMP Cable Cat6

TwistPair in TwistPair Cable Cat6

Ilustration wiring cable speaker using cable cat6