Showing posts with label Power Amplifier. Show all posts
Showing posts with label Power Amplifier. Show all posts

Electronics TA8210AH Stereo Car Power Amplifier

Circuit TA8210AH stereo Car Power amplifier schematics Circuit Electronics,
IC TA8210AH By using this you can apply a series of audio power amplifier is the car audio system. In general, all the speakers in the car using a subwoofer speaker, and woofer. Because the car is not big room so the sound is being required is not too high.

Audio amplifier circuit can work at a minimum voltage 12-volt DC, if supplied under voltage 12-volt amplifier work will be less than the maximum. This amplifier output power up to 200W or 2 x 100W stereo with 8 ohm impedance.
200W car <a href='' title='amplifier circuits'>amplifier</a> schematic

Part List :



R1 =1K

R2 =50K trim

R3 =1K

R4 =50K trim

R5 =680R

R6 =680R

R7 =150K

R8 =2R2

R9 =2R2




C1 =1uF

C2 =1uF

C3 =47uF

C4 =47uF

C5 =100n/400V

C6 =220uF

C7 =220uF

C8 =100n/400V

C9 =100n/400V


Intregated Circuit



X2-3=in R


X2-1=in L

X1-1,X1-2=Out R

X1-3,X1-4=Out L
Schematics for TA8210AH stereo Car Power amplifier Circuit Electronics
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Schematic Superb Power Amplifier using TDA7250 Circuit Diagrams

Circuit Superb Power amplifier using TDA7250 schematics Circuit Electronics,

This 2-channel hybrid IC is normally configured with TIP142/147 power darlingtons for its' output. For those who prefer to use power transistors instead, the TDA7250 can easily be converted. All that is required are a few transistors, 4 additional resistors and some rewiring.

This conversion centers mainly on changing the output section to a Sziklai.

Sziklai Output

In our IA502 on the right, drivers Q1,Q2 are 2SC2238 and 2SA968, and outputs Q5,Q6 are 2SA1216 and 2SC2922 respectively.

No instability problems were encountered from this conversion. After a period of run-in, the amplifier remained thermally stable.

Is this version worth the extra cost and effort?

If one is only interested in something basic, the TIP version would be sufficient. But if one is after sonic performance, I would recommend this version.

2SC2922/2SA1216 hardwired

the TDA7250 ic

Schematics for Superb Power amplifier using TDA7250 Circuit Electronics
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Schematic 2SJ113/2SK399 SEPP AB-40W stereo power amplifier, no feedback, the DC system Circuit Diagrams

Circuit 2SJ113/2SK399 SEPP AB-40W stereo power amplifier, no feedback, the DC system schematics Circuit Electronics,
MJ wireless experiment in 1992 and announced in June

MOS-FET power output stage, a simple voltage・Miller called the NFB minor loops in multiplied by a powerful, and put on overalls with the NFB, has achieved very low output impedance, the natural sound of the amplifier.

Lead chassis S4 (300 × 200 × 60) is used. Both sides in the handmade SHIMASHITA wood paneling.
Block on the chassis are amplified voltage capacitors and a small stage for those who for the power transformer and the radiator and looks imposing, but the real thing is compact and lightweight.
Input terminals and output terminals to a lot of effort SUPATORON.
At the bottom of the radiator board配SHI MOS-FET power output stage and to shorten the wiring, the gate入RENAKU series resistance does not even oscillation.
Just change a little wiring, the source follower circuit voltage circuits in the mirror can be changed.
Miller-voltage operating conditions of the basic design is satisfactory, the source follower to change to get high-quality sound.

Miller-voltage circuit

Miller-voltage circuit and, as shown in Figure 1, MOS-FET source follower circuit and facing each other, the zero-bias operation to add J-FET, multiplied by the output stage to return to the local circuit.

[Figure 1] The output stage of the library
J-FET drain side of the drive and a collector of Tr-stage gate MOS-FET, so it is high impedance.
Pch Nch of the J-FET drain and between the MOS-FET INBIDANSU low bias power are combined with V B.

Therefore, the drive signal from the current stage, I S, J-FET to the source of the flow resistance R S, J-FET source of the signal voltage V S to occur, MOS-FET to the source of power equal to V S V O voltage can be obtained.

J-FET drain side of the higher impedance Z D, the output impedance of Z O will be reduced, MOS-FET input capacity of Cis (all seen from the side of the gate capacity, and will include feedback capacity) to I see a higher frequency and lower Z D, Z O increases.

MOS-FET gate - source voltage V GS, at a maximum and not more than V B, the maximum drain current I D is limited in quantity, so the effect of preventing excessive current may have up to two out of The current limit action in the clip must be designed to SHIMAWANAI.
The MOS-FET, the threshold voltage V GS (th) g m and the highest transconductance is desirable.
Fortunately, switching for the rich in power MOS-FET, but the request was consistent with many.

The design of this machine

MOS-FET used in Hitachi 2SJ113/2SK399 to.
Figure 2 shows the transmission characteristics.

1A and the idling current I O and Figure 2 and V GS is the extent to 5V, V B of the V GS is about twice the 10V.

[Figure 2] 2SJ113/2SK399 V GS-I D characteristics of
V GS to take a maximum of 2SJ113/2SK399 the aforementioned principles of the V B is less than 10V.

V GS in the case of a 9V about 9A So I D, 2Ω load resistance of the output voltage is also available in 18V, low enough to bear the load impedance.

For the basic design of the circuit is shown in Figure 3.

[Figure 3] The basic design of this machine

Power transformer, the tango TOROIDARUTORANSU using the RS-3101, the output stage supply voltage V DD is about 32V.

I O V B significantly higher if you set it, I D at the current clip can be larger, while the MOS-FET to increase the amount of heat, P CH channels of loss over the amount of allowable because This machine, and I O is 1A.

[Figure 4] heat dissipation design

Table 1 from the standard table P CH = 100W (Ta = 25 ℃), T CH = 150 ℃, so

Heat inside the θ i resistors θ i = (T CH - T a) / P CH = (150 ℃ - 25 ℃) / 100W = 1.25 ℃ / W.

DENKA TO-3P heat sheet using the MOS-FET and the thermal resistance between the radiator, Contact thermal resistance thermal insulation resistance θ c + θ s = 0.75 ℃ / W.

Below is a circuit diagram of the heat conduction.

P CH = V DD I C = 32V × 1A = 32W, so Radiator will be allowed to seek maximum temperature T f,

T f = T CH - P CHics =150℃ -32W×(1.25℃/W +0.75℃/W ) = 86℃

Ta ambient temperature of the radiator in the case of 50 ℃, The maximum permissible radiator heat resistance,

θ f = ( T f - T a )/ P CH = ( 86℃-50℃ )/32W =1.125℃/W

Figure 4 design radiating from the radiator to keep the temperature must be below 86 ℃.
Therefore, the radiator of a flexible TF1212 (122x120 × 40) in four pieces, MOS-FET is attached by a single, open-style chassis and put on.

Bias circuit as shown in Figure 5, V B less than 1 ~ 2V zener diode voltage and low anti-adjustable instrument (VR) has been able to adjust.

[Figure 5] Bias Circuit

The circuit and cause a bad contact VR, I O is on the rise as a dangerous, VR is reliable in use. CRD Diode, SEMITEC Japan = E102 0.88 - 1.32 mA, 10V

The constant voltage bias circuitry to operate a minimum of about 2mA current I L.

Miller-voltage circuits used in the local feedback 2SJl08/2SK370 of the J-FET I DSS 5.5mA is ranked GR, g m and the same amount if I DSS, and other forms of J-FET is also available.

The output stage for a full swing to V S necessary, to afford to ± 30V, R S at the time that I S 2.2kΩ is in full swing is ± 14mA.
When you, 2SJl08/2SK370 current flowing through the gate area covered Tr, is the gate to the low-impedance does not affect operation.

Tr stage of the drive for the operating current I S I S I SO that is half the 7mA, drive circuit and locally Biasing stage of the J-FET feedback circuitry necessary to operate because of the current sources of supply, drive stage Tr I DO idling current of the

I DO > I L + I DSS + I SO I DO> I L + I DSS + I SO
= 2mA+5.5mA+7mA = 2mA +5.5 mA +7 mA
=14.5mA = 14.5mA

'91 Of the amplify circuit voltage in the February issue of its MOS-FET DARINTONANPU INBATEDDO as well as two-stage amplification of the no-return.

FET first dan level of the output stage with zero bias 2SJ108/2SK370 behavior is the same.

Figure 3 is a constant,
I DO = ( R DI DSS - V BE ) / R E I DO = (R D I DSS - V BE) / R E
=(1kΩ×5.5mA-0.6V)/0.27kΩ = (1kΩ × 5.5mA-0.6V) / 0.27kΩ
=18mA = 18mA
Thus, the above conditions are satisfied.

If I DSS is a small increase in R S and will need constant change.

In addition, R S of the increase can be, if滅RASHITA Conversely, 1.8kΩ below the oscillator to the output stage.
NFB also put to the Ministry of voltage amplification, or as the output stage of the oscillation Darlington to make it easier to connect.
Such circuits, in order to prevent oscillation, MOS-FET and the gate necessary to insert a resistance in series there.

The circuit of the machine

All of the library circuit is shown in Figure 6.

[Figure 6] The circuit of the machine

Amp circuit parts

Change of source follower

Part of the power circuit

The amplification of the first dan level voltage, FET to cover the cascode-voltage connection was made.

To amplify the power of the voltage, the power to reduce noise and crosstalk, CR put filters.

To prevent oscillation, MOS-FET's drain and capacitor ground connection between the wiring to a minimum.
This type of capacitor used in a significant impact on the stability of this machine 1μF use of multilayer ceramic capacitors, in a square wave output waveform was able to reduce ringing.

In making this standard to guarantee performance, Tr KONPURIMENTARIPEA and keep FET using a commercially available, and no resistance to the 5 percent level used in the selection.
A pair of strict screening device, and using high-precision resistance, to get the balance of push-pull, you can further reduce distortion.

The machines used in the standard device is shown in Table 1.

In addition, the unit of the standard elements of a possible substitute.

[Table 1] FET, Tr standards

Maximum Ratings (Ta = 25 ℃, * Tc = 25 ℃)

Electrical Characteristics (Ta = 25 ℃)




T j


g m

C is

Electrodes connected
Model name












-2.6~ -20














* P CH


V GS(th)

g m

C is












-2~ -5















T j

f T

C ob




h FE























T j

f T

C ob




h FE




















The production of this aircraft

A4-size chassis lead the S4 (300 × 200 × 60).

Impossible without wiring and components acrobatics on the use of the mounting, as long as stylized as a result of how the parts are in place, but not from the beginning rather than in accordance with such style, the best components and circuitry It is thought to want a place. High-current circuit in order to shorten the wiring, 22000μF blocks of storage capacitors on the inside of the chassis.

Processing of the chassis, radiator and cooling radiator for the better part of the mounting, to increase stiffness of thick reinforced with aluminum angle.

YASURI chassis in the welding marks from flat paint and Trim can be

Decoration on the front of the word processor in a black plastic sheeting was printed in gold ribbon stickers on their own.

For the board, copper foil for printed circuit board wiring can not be used as a vapor.
As a result of the library board, as in Figure 7, the bull's-eye of the copper foil substrate in the etching solution to remove the lead wire through a hole in the expansion of 2mm in diameter, and bring out the wiring in place of a single wire fault of 0.8mm thickness Strange.

[Figure 7] of the library board

The upper parts of the board layout

zu7.gif (24134 bytes)

Place the bottom part of the board

Change of source follower

zu7u.gif (23743 bytes)zu7s.gif (12518 bytes)
MOS-FET from the board to speed up the wiring, the board placed part of the mounting position, I sent a particular concern.

Tr two-stage during the drive, angled aluminum heat sinks are attached to the tie, the heat of the earth plate connected to the substrate, and the chassis may not have any contact.

FET complementary characteristics , so the thermal drift, it is binding, so the heat on this machine is not binding.

Upper and lower parts of the substrate is mounted on both sides, and are cross-wired to the stereo, not making a mistake when you have good circuit diagram and to see that match.

Power supply circuit, the capacitor blocks from the terminal Rch Lch and wiring into two strains, and 100Ω equalizer voltage amplifier attached to the plate to lag, the output of the idling current stage of the resistance to check the terminal block 0.47Ω Mounted on.

The output signal Q8, Q9 and the gate of 2.2kΩ extracted from the Earth's is a logical.
Therefore, Q10, Q11 from the source of Q8, Q9 Hye-wiring of the gate, which are then wired to the output pins.

But from the supply side of the Earth Hye 2.2kΩ, and the output pins and wiring.

Rectifier diode from the wiring to emit intense RIPPURUNOIZU other引KI回SHIMASU do not interfere with wiring.

MOS-FET gate of the current-carrying wires and open and the input capacity is in charge of the gate voltage to drain excessive current to flow, so beware of destruction.

Adjustment of the machine

Before the adjustment of the resistance VR 1 and VR 2 to leave the minimum value.

Turn the first time, in case of emergency drain and power MOS-FET 10Ω10W between the need to connect to the resistance.

Turn the output within ± 2V DC voltage, 10Ω peers verify voltage is less than 10V.

10Ω would remove the anomaly, the wiring back to normal.

The first adjustment, and idling for 1A current, VR 2 to adjust the voltage of 0.47V at both ends 0.47Ω.

If the VR 2, it is up to 0.47V If the VR 2 in the series with less than 1 ~ 2kΩ resistance in the case, contrary to 0.47V as VR 2 more than the minimum if the HZ-HZ-9L zener diode 7L exchange.

After idling 0.47Ω current settings and leave a short circuit.

DC output voltage to 0V and then to adjust the VR 1, but the power of the state暖MAっcold and heat until a stable condition change DC voltage output to 0V in any state. The machines fluctuation band around the center of the 0V.

Turn the VR 1 to increase output if the DC voltage, Q 1 source of 390Ω

After more than a measurement of adjustment, and later was able to get the property.

Changes to the source follower circuit

Lower SOSUFO If you compare the change in voltage that Miller was going to show excellence, excellence is fundamental to the circuit, the source follower of the great qualities who is also my best MASHITA.

Miller FOROWAHE voltage changes from the source, Figure 6, Figure 7, as shown in the return of local resistance to remove the FET switching can be a simple, so one can enjoy as much of the amplifier.

After the changes increase Idling a little current, so the re-adjustment is required.

In addition, changes to the circuit in the switch is no more acceptable.

The longer the oscillation circuit will be easier if the switch is running a poor contact and damage the cause of switching from the speakers.

In addition, a source follower of the voltage amplifier if you want to change the mirror, mirror voltage as the above-mentioned constraints must be met.

The characteristics of this machine

Figure 8 characteristics and the frequency of the Figure 9 crosstalk characteristics of the source and the voltage follower without a difference in the mirror, and accepted the good characteristics of the vocal cord is in the region.

RESUBONSU the high-growing region because of the high-frequency signals of the MOS-FET input current capacity can be passed through the gates - the source of signal voltage between the decrease in cost.

[Figure 8] frequency characteristics.
zu8.gif (14832 bytes)

[Figure 9] characterization of crosstalk
zu9.gif (17063 bytes)

Figure 10 is characteristic of the distortion, and frequency for each individual to move parallel to the low-voltage Mirror, low-frequency effects of a localized because of the high return rate is a low distortion.

[Figure 10] distortion characteristics
zu10.gif (21832 bytes)

Figure 11・damping factor characteristic of the low-frequency BORUTE JIMIRA If there are more than 1,000 from 600Hz to 100kHz while much is falling in a straight line.
The cause, MOS-FET input will increase capacity and frequency for the local decrease in the amount of feedback.
Meanwhile, the case source follower, about 20 in the regional auditory zone is nearly constant. This is like a personality characteristics of each other's differences, which divide the sound quality is a factor.

[Figure 11] damping factor characteristics・
zu11.gif (18643 bytes)

Then resist Load by 10kHz square wave output waveform of the load and capacity are shown in the photos.

Enlarge to rise again to display the waveform, the ringing is legible.

10kHz square wave output waveform Photo
SOSU・FOROWA Miller voltage・

8Ω load 4Vp-p

8Ω load 4Vp-p

sf8.gif (34662 bytes)vm8.gif (46892 bytes)

0.1μF load

0.1μF load

sf01.gif (35640 bytes)vm01.gif (36468 bytes)

0.47μF load

0.47μF load

sf047.gif (38284 bytes)vm047.gif (35653 bytes)

8Ω +0.1 μF load 4Vp-p

8Ω load 55Vp-p

sf801.gif (36849 bytes)vm55.gif (34460 bytes)
Miller-source voltage follower and stability in both high-capacity load is not on the oscillation.
High stability and the improvement of property ambivalent relationship with, is a difficult balance.

The high-range aircraft to more than necessary that the property did not extend to higher depreciation was available taxis.

ON-OFF at the time of supply shocks 0.5Vp-p less noise and lower the residual noise Rch 140μV, Lch, and it also reduces the 130μV, and silence the cry of power transformer in the extra care.

The temperature of the radiator, but if you do not mind the location of the ventilation, can not be touched by hand and the heat is not enough.

The sound quality of the natural voltage moist Miller faction, the source follower and a faction a spectacular reduction of the thick, and to insist on individuality, both of which are difficult to discard, the悩MIMASU choice, but only if producers Can enjoy luxury.

Schematics for 2SJ113/2SK399 SEPP AB-40W stereo power amplifier, no feedback, the DC system Circuit Electronics
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Schematic Discreet Power Amplifier Great Sound and low cost Circuit Diagrams

Circuit Discreet Power amplifier Great Sound and low cost schematics Circuit Electronics,
Before proceeding further define discreet: Discreet is not continuous in mathematics relates to the natural numbers and whole and electronics is the central concept of a circuit implemented by the minimum component: transistors, resistors, capacitors, etc., without the use of integrated circuits that meet them within several of these components.

There are several series, the TDA, LM, STK, ... Its sound quality does not meet the required quality in the topic at hand. Because they are designed to get good numbers, do not focus on correcting distortions before they occur and are based on principle and expired in engineering in this field.

You need to do more instead of relying on the good performance feedback. The feedback correcting the distortion, but adds its own and this is the whiting that bites its tail, a club which adds distortion correction. The distortions produced by this technique are difficult to measure and almost never done, aside from the low correlation between the figures (THD, IMD ,...) and hearing as they are raised. Why do they sound good valves with THD between 0.3 and 3%?.

Read More....

Schematics for Discreet Power amplifier Great Sound and low cost Circuit Electronics
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Schematic TDA7294 DC Servo Amplifier current negative feedback Circuit Diagrams

Circuit TDA7294 DC Servo amplifier current negative feedback schematics Circuit Electronics, TDA7294 DC Servo <a href='' title='amplifier circuits'>amplifier</a> current negative feedback
In the field of consumer reports electronics products reviews, product size, weight is toward smaller, lighter direction, high-power single-chip audio power amplifier needs of increasingly prominent, TDA7294 is currently the best performance, the biggest single-chip audio power amplifier One.

It consists of the European SGS-THOMSON Italian-French company in accordance with discrete components A and B audio amplifier circuit design from classic. Its former low-level noise, low distortion of the bipolar transistor circuit, at the end of a high-pressure, high current DMOS output of the buffer, it has bipolar circuit sounds pure merit, have large current high voltage FET Driver output characteristics.

Since 1998 TDA7294 introduced to China so far, I believe that many enthusiasts have been TDA7294 delicate taste, natural sound. Regrettably, however, is that they have heard only negative feedback is standard voltage of the voice amplifier.

And negative feedback amplifier voltage than current negative feedback amplifier as excellent transient nonlinear distortion and intermodulation distortion characteristics, the frequency amplifier curve flat, high and low frequency response more exhibition wide; more important is that circuit Will load impedance into the feedback network, it can change the speakers of such fierce resistance to the load compensation, coupled with stable and reliable performance, than the negative feedback voltage amplifier has more advantages, the current negative feedback current amplifier is widely For the modern high-fidelity audio amplifier.

Figure 1 circuit is an excellent performance, improve the design of the fever-100 W × 2 DC Servo Amplifier current negative feedback stereo amplifier, formed by the two TDA7294, the frequency response of 10 Hz ~ 100kHz. The use of sophisticated audio Yun-double as the two-channel amplifier DC Servo Amplifier output. Speakers from the protection of ASIC μPC1237HA driver completed the relay switch-mute and amplifier output DC offset protection, and other speakers. When the AC power plug, the relay will be delayed for some time speakers access amplifier; disconnecting the AC power when, μPC1237HA detected exchange loss, immediately disconnect the speaker to relay, the amplifier is the complete elimination of the set, Shutting down the transition process the impact of noise on the speakers.

In actual use, taking into account the electricity grid fluctuations Rectifier amplifier output voltage ± Vs volatile, in order to avoid over-voltage and high temperature in the state of damage TDA7294 (Note pressure in the temperature of 25 under the conditions, if the temperature exceeds 25 , TDA7294 the value will subsequently reduce the pressure), the exchange recommended equalizer voltage transformer CT-AC26V × 2.


Speaker to use B & W601, CD machine Marantz CD-19, compared TDA7294 amplifier for the negative feedback standard voltage lines. Software programs at Cai Qin, "the film" test the human voice, Mutebutsi trial String, RR's "Tutti" dynamic test, Rubinstein "Chopin Nocturne" trial piano.

The results are as follows:

In a dynamic sense of speed, the two amplifier very close, but the sound on the current negative feedback is obviously more sweet; the string, the human voice like the rendering software for a warmer, the details of the re-orientation; due to current negative feedback circuit Impedance of the compensation, the low-band high-impedance output has been strengthened, so dive in the low-frequency and intensity of the depth occupied obvious advantage.

Current negative feedback in addition to direct stereo amplifier for CD, VCD, DVD, and other music source amplifier, but also with audio processing unit for use by different combinations of the playback effect.

Schematics for TDA7294 DC Servo amplifier current negative feedback Circuit Electronics
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Schematic Project of circuit potent audio amplifier with TDA7294 Circuit Diagrams

Circuit Project of circuit potent audio amplifier with TDA7294 schematics Circuit Electronics, Super amplifier with tda7294 of the St microeletronics, is possible to get potency of up to 100W in an only chip, for an unit stereo to use two same to that. That circuit is based on the datasheet of the ready

to work with sources of strong signs, in case it is necessary it uses a pré-amplifier in the form of an opamp. That circuit type with integrated circuit is ideal for systems of involving sound. Because he is quite compact could use an independent amplifier for each one of the high speakers. In that way it can be to share the source dimensioned it is clear to support all the connected amplifiers. Oh you can remove a wave with that neighbor that bought a " home theater " of 1000W PMPO, and fear in saying that is an enormous potency, when in reality it will verify the real potency of the equipment it doesn't arrive nor to 10W RMS for channel. It already imagined a system of high active speakers with 80W. If it will pass for the marketing department, that where defines the potency PMPO, your system would give... it lets me to see... comparing with the example oh of top... about " 3000 W PMPO ". Game that you have been doing with the potency of the equipments. For you to do your sound system will only need the sign source. Because the amplifier can be perfectly that of here. The necessary subwoofer of a little more of potency then in the datasheet you will find an assembly example in bridge to increase the potency. Below we have the schematic, the Printed circuit board and details of the assembly.

Good luck.

dmos 100v 100ww power <a href='' title='audio circuits'>audio</a> <a href='' title='amplifier circuits'>amplifier</a> with mute stand-by

schematic - diagram circuit for assembly power amplifier tda7294

schematic diagram of circuit for tda7294

Suggestion of Printed circuit board to assembly the power amplifier with tda7294

printed circuit board for <a href='' title='amplifier circuits'>amplifier</a> <a href='' title='audio circuits'>audio</a> potent with tda7294

Side of the components to assembly potent amplifier with TDA7294

Plate side of the components tda7294 3d image for <a href='' title='amplifier circuits'>amplifier</a> tda7294

lists of components: for tda7294

C1 1µF
C2 47µF
C3 10µF
C4 10µF
C5 22µF
C6 4700µF/50V
C7 100N
C8 4700µF/50V
C9 100N
D1 1N4148
R1 22K
R2 680R
R3 22K
R4 22K
R5 30K
R6 10K
SL1 key de Mute
SL2 signal input (Line In)
U1 TDA7294V
X2 Connector AK300/3
X3 Connector AK300/2
several: Printed circuit board, power source +35 -35V / 6A, etc

Schematics for Project of circuit potent audio amplifier with TDA7294 Circuit Electronics
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