To manufacture a structure based on an integral ULF, a minimum of attached parts is required. The use of known-good components ensures high repeatability and, as a rule, no additional tuning is required.
The given typical switching circuits and main parameters of integrated ULFs are designed to facilitate the orientation and selection of the most suitable microcircuit.
For quadraphonic ULFs, the parameters in bridged stereo are not specified.
TDA1010
Supply voltage - 6...24 V
Output power (Un =14.4 V, THD = 10%):
RL=2 Ohm - 6.4 W
RL=4 Ohm - 6.2 W
RL=8 Ohm - 3.4 W
SOI (P=1 W, RL=4 Ohm) - 0.2%
TDA1011
Supply voltage - 5.4...20 V
Maximum current consumption - 3 A
Un=16V - 6.5 W
Un=12V - 4.2 W
Un=9V - 2.3 W
Un=6B - 1.0 W
SOI (P=1 W, RL=4 Ohm) - 0.2%
TDA1013
Supply voltage - 10...40 V
Maximum current consumption - 1.5 A
Output power (THD=10%) - 4.2 W
TDA1015
Supply voltage - 3.6...18 V
Output power (RL=4 Ohm, THD=10%):
Un=12V - 4.2 W
Un=9V - 2.3 W
Un=6B - 1.0 W
SOI (P=1 W, RL=4 Ohm) - 0.3%
TDA1020
Supply voltage - 6...18 V
RL=2 Ohm - 12 W
RL=4 Ohm - 7 W
RL=8 Ohm - 3.5 W
TDA1510
Supply voltage - 6...18 V
Maximum current consumption - 4 A
THD=0.5% - 5.5 W
THD=10% - 7.0 W
TDA1514
Supply voltage - ±10...±30 V
Maximum current consumption - 6.4 A
Output power:
Un =±27.5 V, R=8 Ohm - 40 W
Un =±23 V, R=4 Ohm - 48 W
TDA1515
Supply voltage - 6...18 V
Maximum current consumption - 4 A
RL=2 Ohm - 9 W
RL=4 Ohm - 5.5 W
RL=2 Ohm - 12 W
RL4 Ohm - 7 W
TDA1516
Supply voltage - 6...18 V
Maximum current consumption - 4 A
Output power (Un =14.4 V, THD = 0.5%):
RL=2 Ohm - 7.5 W
RL=4 Ohm - 5 W
Output power (Un =14.4 V, THD = 10%):
RL=2 Ohm - 11 W
RL=4 Ohm - 6 W
TDA1517
Supply voltage - 6...18 V
Maximum current consumption - 2.5 A
Output power (Un=14.4B RL=4 Ohm):
THD=0.5% - 5 W
THD=10% - 6 W
TDA1518
Supply voltage - 6...18 V
Maximum current consumption - 4 A
Output power (Un =14.4 V, THD = 0.5%):
RL=2 Ohm - 8.5 W
RL=4 Ohm - 5 W
Output power (Un =14.4 V, THD = 10%):
RL=2 Ohm - 11 W
RL=4 Ohm - 6 W
TDA1519
Supply voltage - 6...17.5 V
Maximum current consumption - 4 A
Output power (Up=14.4 V, THD=0.5%):
RL=2 Ohm - 6 W
RL=4 Ohm - 5 W
Output power (Un =14.4 V, THD = 10%):
RL=2 Ohm - 11 W
RL=4 Ohm - 8.5 W
TDA1551
Supply voltage -6...18 V
THD=0.5% - 5 W
THD=10% - 6 W
TDA1521
Supply voltage - ±7.5...±21 V
Output power (Un=±12 V, RL=8 Ohm):
THD=0.5% - 6 W
THD=10% - 8 W
TDA1552
Supply voltage - 6...18 V
Maximum current consumption - 4 A
Output power (Un =14.4 V, RL = 4 Ohm):
THD=0.5% - 17 W
THD=10% - 22 W
TDA1553
Supply voltage - 6...18 V
Maximum current consumption - 4 A
Output power (Up=4.4 V, RL=4 Ohm):
THD=0.5% - 17 W
THD=10% - 22 W
TDA1554
Supply voltage - 6...18 V
Maximum current consumption - 4 A
Output power (Up = 14.4 V, RL = 4 Ohm):
THD=0.5% - 5 W
THD=10% - 6 W
TDA2004
Supply voltage - 8...18 V
Output power (Un=14.4 V, THD=10%):
RL=4 Ohm - 6.5 W
RL=3.2 Ohm - 8.0 W
RL=2 Ohm - 10 W
RL=1.6 Ohm - 11 W
KHI (Un=14.4V, P=4.0 W, RL=4 Ohm) - 0.2%;
Bandwidth (at -3 dB level) - 35...15000 Hz
TDA2005
Dual integrated ULF, designed specifically for use in cars and allowing operation with low-impedance loads (up to 1.6 Ohms).
Supply voltage - 8...18 V
Maximum current consumption - 3.5 A
Output power (Up = 14.4 V, THD = 10%):
RL=4 Ohm - 20 W
RL=3.2 Ohm - 22 W
SOI (Uп =14.4 V, Р=15 W, RL=4 Ohm) - 10%
Bandwidth (level -3 dB) - 40...20000 Hz
TDA2006
Integrated ULF, providing a high output current, low harmonic content and intermodulation distortion. The location of the pins coincides with the location of the pins of the TDA2030 microcircuit.
Supply voltage - ±6.0...±15 V
Maximum current consumption - 3 A
Output power (Ep=±12V, THD=10%):
at RL=4 Ohm - 12 W
at RL=8 Ohm - 6...8 W THD (Ep=±12V):
at P=8 W, RL= 4 Ohm - 0.2%
at P=4 W, RL= 8 Ohm - 0.1%
Bandwidth (at -3 dB level) - 20...100000 Hz
Consumption current:
at P=12 W, RL=4 Ohm - 850 mA
at P=8 W, RL=8 Ohm - 500 mA
TDA2007
Dual integrated ULF with single-row pin arrangement, specially designed for use in television and portable radio receivers.
Supply voltage - +6...+26 V
Quiescent current (Ep=+18 V) - 50...90 mA
Output power (THD=0.5%):
at Ep=+18 V, RL=4 Ohm - 6 W
at Ep=+22 V, RL=8 Ohm - 8 W
SOI:
at Ep=+18 V P=3 W, RL=4 Ohm - 0.1%
at Ep=+22 V, P=3 W, RL=8 Ohm - 0.05%
Bandwidth (at -3 dB level) - 40...80000 Hz
TDA2008
Integrated ULF, designed to operate on low-impedance loads, providing high output current, very low harmonic content and intermodulation distortion.
Supply voltage - +10...+28 V
Quiescent current (Ep=+18 V) - 65...115 mA
Output power (Ep=+18V, THD=10%):
at RL=4 Ohm - 10...12 W
at RL=8 Ohm - 8 W
SOI (Ep= +18 V):
at P=6 W, RL=4 Ohm - 1%
at P=4 W, RL=8 Ohm - 1%
Maximum current consumption - 3 A
TDA2009
Dual integrated ULF, designed for use in high-quality music centers.
Supply voltage - +8...+28 V
Quiescent current (Ep=+18 V) - 60...120 mA
Output power (Ep=+24 V, THD=1%):
at RL=4 Ohm - 12.5 W
at RL=8 Ohm - 7 W
Output power (Ep=+18 V, THD=1%):
at RL=4 Ohm - 7 W
at RL=8 Ohm - 4 W
SOI:
at Ep= +24 V, P=7 W, RL=4 Ohm - 0.2%
at Ep= +24 V, P=3.5 W, RL=8 Ohm - 0.1%
at Ep= +18 V, P=5 W, RL=4 Ohm - 0.2%
at Ep= +18 V, P=2.5 W, RL=8 Ohm - 0.1%
Maximum current consumption - 3.5 A
TDA2030
Supply voltage - ±6...±18 V
Quiescent current (Ep=±14 V) - 40...60 mA
Output power (Ep=±14 V, THD = 0.5%):
at RL=4 Ohm - 12...14 W
at RL=8 Ohm - 8...9 W
SOI (Ep=±12V):
at P=12 W, RL=4 Ohm - 0.5%
at P=8 W, RL=8 Ohm - 0.5%
Bandwidth (at -3 dB level) - 10...140000 Hz
Consumption current:
at P=14 W, RL=4 Ohm - 900 mA
at P=8 W, RL=8 Ohm - 500 mA
TDA2040
Integrated ULF, providing high output current, low harmonic content and intermodulation distortion.
Supply voltage - ±2.5...±20 V
Quiescent current (Ep=±4.5...±14 V) - mA 30...100 mA
Output power (Ep=±16 V, THD = 0.5%):
at RL=4 Ohm - 20...22 W
at RL=8 Ohm - 12 W
THD (Ep=±12V, P=10 W, RL = 4 Ohm) - 0.08%
Maximum current consumption - 4 A
TDA2050
Integrated ULF, providing high output power, low harmonic content and intermodulation distortion. Designed to work in Hi-Fi stereo systems and high-end TVs.
Supply voltage - ±4.5...±25 V
Quiescent current (Ep=±4.5...±25 V) - 30...90 mA
Output power (Ep=±18, RL = 4 Ohm, THD = 0.5%) - 24...28 W
SOI (Ep=±18V, P=24Wt, RL=4 Ohm) - 0.03...0.5%
Bandwidth (at -3 dB level) - 20...80000 Hz
Maximum current consumption - 5 A
TDA2051
Integrated ULF, which has a small number of external elements and provides low harmonic content and intermodulation distortion. The output stage operates in class AB, which allows for greater output power.
Output power:
at Ep=±18 V, RL=4 Ohm, THD=10% - 40 W
at Ep=±22 V, RL=8 Ohm, THD=10% - 33 W
TDA2052
Integrated ULF, the output stage of which operates in class AB. Accepts a wide range of supply voltages and has a high output current. Designed for use in television and radio receivers.
Supply voltage - ±6...±25 V
Quiescent current (En = ±22 V) - 70 mA
Output power (Ep = ±22 V, THD = 10%):
at RL=8 Ohm - 22 W
at RL=4 Ohm - 40 W
Output power (En = 22 V, THD = 1%):
at RL=8 Ohm - 17 W
at RL=4 Ohm - 32 W
SOI (with a passband at the level of -3 dB 100... 15000 Hz and Pout = 0.1... 20 W):
at RL=4 Ohm -<0,7 %
at RL=8 Ohm -<0,5 %
TDA2611
Integrated ULF designed for use in household equipment.
Supply voltage - 6...35 V
Quiescent current (Ep=18 V) - 25 mA
Maximum current consumption - 1.5 A
Output power (THD=10%): at Ep=18 V, RL=8 Ohm - 4 W
at Ep=12V, RL=8 0m - 1.7 W
at Ep=8.3 V, RL=8 Ohm - 0.65 W
at Ep=20 V, RL=8 Ohm - 6 W
at Ep=25 V, RL=15 Ohm - 5 W
THD (at Pout=2 W) - 1%
Bandwidth - >15 kHz
TDA2613
SOI:
(Ep=24 V, RL=8 Ohm, Pout=6 W) - 0.5%
(En=24 V, RL=8 Ohm, Pout=8 W) - 10%
Quiescent current (Ep=24 V) - 35 mA
TDA2614
Integrated ULF, designed for use in household equipment (television and radio receivers).
Supply voltage - 15...42 V
Maximum current consumption - 2.2 A
Quiescent current (Ep=24 V) - 35 mA
SOI:
(Ep=24 V, RL=8 Ohm, Pout=6.5 W) - 0.5%
(Ep=24 V, RL=8 Ohm, Pout=8.5 W) - 10%
Bandwidth (level -3 dB) - 30...20000 Hz
TDA2615
Dual ULF, designed for use in stereo radios or televisions.
Supply voltage - ±7.5...21 V
Maximum current consumption - 2.2 A
Quiescent current (Ep=7.5...21 V) - 18...70 mA
Output power (Ep=±12 V, RL=8 Ohm):
THD=0.5% - 6 W
THD=10% - 8 W
Bandwidth (at level -3 dB and Pout = 4 W) - 20...20000 Hz
TDA2822
Dual ULF, designed for use in portable radios and television receivers.
Supply voltage - 3...15 V
Quiescent current (Ep=6 V) - 12 mA
Output power (THD=10%, RL=4 Ohm):
Ep=9V - 1.7 W
Ep=6V - 0.65 W
Ep=4.5V - 0.32 W
TDA7052
TDA7053
TDA2824
Dual ULF designed for use in portable radio and television receivers
Supply voltage - 3...15 V
Maximum current consumption - 1.5 A
Quiescent current (Ep=6 V) - 12 mA
Output power (THD=10%, RL=4 Ohm)
Ep=9 V - 1.7 W
Ep=6 V - 0.65 W
Ep=4.5 V - 0.32 W
THD (Ep=9 V, RL=8 Ohm, Pout=0.5 W) - 0.2%
TDA7231
ULF with a wide range of supply voltages, designed for use in portable radios, cassette recorders, etc.
Supply voltage - 1.8...16 V
Quiescent current (Ep=6 V) - 9 mA
Output power (THD=10%):
En=12B, RL=6 Ohm - 1.8 W
En=9B, RL=4 Ohm - 1.6 W
Ep=6 V, RL=8 Ohm - 0.4 W
Ep=6 V, RL=4 Ohm - 0.7 W
Ep=3 V, RL=4 Ohm - 0.11 W
Ep=3 V, RL=8 Ohm - 0.07 W
THD (Ep=6 V, RL=8 Ohm, Pout=0.2 W) - 0.3%
TDA7235
ULF with a wide range of supply voltages, designed for use in portable radio and television receivers, cassette recorders, etc.
Supply voltage - 1.8...24 V
Maximum current consumption - 1.0 A
This article will discuss a fairly common and popular amplifier chip TDA7294. Let's look at its brief description, technical characteristics, typical connection diagrams and give a diagram of an amplifier with a printed circuit board.
Description of the TDA7294 chip
The TDA7294 chip is a monolithic integrated circuit in a MULTIWATT15 package. It is intended for use as an AB Hi-Fi audio amplifier. Thanks to its wide supply voltage range and high output current, the TDA7294 is capable of delivering high output power into 4 ohm and 8 ohm speaker impedances.
The TDA7294 has low noise, low distortion, good ripple rejection, and can operate from a wide range of supply voltages. The chip has built-in short circuit protection and an overheat shutdown circuit. The built-in Mute function makes it easy to control the amplifier remotely, preventing noise.
This integrated amplifier is easy to use and does not require many external components to function properly.
TDA7294 Specifications
Chip dimensions:
As stated above, chip TDA7294 is produced in the MULTIWATT15 housing and has the following pinout arrangement:
- GND (common wire)
- Inverting Input
- Non Inverting Input
- In+Mute
- N.C. (not used)
- Bootstrap
- Stand-by
- N.C. (not used)
- N.C. (not used)
- +Vs (plus power)
- Out
- -Vs (minus power)
You should pay attention to the fact that the microcircuit body is connected not to the common power line, but to the power supply minus (pin 15)
Typical TDA7294 connection diagram from datasheet
Bridge connection diagram
Bridged connection is the connection of an amplifier to speakers, in which the channels of a stereo amplifier operate in the mode of monoblock power amplifiers. They amplify the same signal, but in antiphase. In this case, the speaker is connected between the two outputs of the amplification channels. Bridge connection allows you to significantly increase the power of the amplifier
In fact, this bridge circuit from the datasheet is nothing more than two simple amplifiers to the outputs to which an audio speaker is connected. This connection circuit can only be used with speaker impedances of 8 Ohms or 16 Ohms. With a 4 ohm speaker, there is a high probability of the chip failing.
Among integrated power amplifiers, the TDA7294 is a direct competitor to the LM3886.
Example of using TDA7294
This is a simple 70 watt amplifier circuit. Capacitors must be rated for at least 50 volts. For normal operation of the circuit, the TDA7294 chip must be installed on a radiator with an area of about 500 cm2. The installation is carried out on a single-sided board made according to .
Printed circuit board and arrangement of elements on it:
Amplifier power supply TDA7294
To power an amplifier with a 4 Ohm load, the power supply must be 27 volts; with a speaker impedance of 8 Ohms, the voltage should already be 35 volts.
The power supply for the TDA7294 amplifier consists of a step-down transformer Tr1 having a secondary winding of 40 volts (50 volts with a load of 8 Ohms) with a tap in the middle or two windings of 20 volts (25 volts with a load of 8 Ohms) with a load current of up to 4 amperes. The diode bridge must meet the following requirements: forward current of at least 20 amperes and reverse voltage of at least 100 volts. The diode bridge can be successfully replaced with four rectifier diodes with the corresponding indicators.
Electrolytic filter capacitors C3 and C4 are designed mainly to remove the peak load of the amplifier and eliminate voltage ripple coming from the rectifier bridge. These capacitors have a capacity of 10,000 microfarads with an operating voltage of at least 50 volts. Non-polar capacitors (film) C1 and C2 can have a capacity of 0.5 to 4 µF with a supply voltage of at least 50 volts.
Voltage distortions should not be allowed; the voltage in both arms of the rectifier must be equal.
(1.2 Mb, downloaded: 4,035)
Probably any radio amateur is familiar with the microcircuit: simple circuit, good sound quality, low price. I recently decided to take a different perspective when I once again came across an article about the "MF-1" amplifier from Lincor.
This is my first article, it is intended for beginner lovers of good sound. Also presented is a drawing of the PCB and a manufacturing option for the amplifier housing.
My acquaintance did not go very smoothly. At that time there were a lot of fakes. They sometimes burned immediately when the power was first applied, and if they started up, they produced not a sound, but something vaguely reminiscent of it, which made me want to pour gasoline on the board and set it on fire, get rid of this ULF and never think about it. Maybe the reason for this was also my inexperience, or maybe the topology of the board I made myself, measuring 35x45 mm (when I remember that board, the author gets big goose bumps all over his body).
After reading, the decision was made to build according to the following criteria:
1) a clean terminal without a volume control (the amplifier works in conjunction with a PC, and the sound is regulated from it),
2) 2 amplification channels according to the double mono scheme (there were 2 transformers from UM Vega,
3) lower coefficient. interpenetration of channels and beautiful stereo),
4) forced cooling using 2 computer coolers and fans at low speeds,
5) and all this must be in the case in the form of a finished structure, which is not a shame to post on Datagor.
My version of PP
The housing, oddly enough, was a homemade amplifier of my neighbor, a former radio amateur, assembled in the housing of an unknown laboratory device. The amp was placed on the landing because... He no longer needed it, and it was a pity to throw it in the trash. I remembered this case when I decided to assemble the MF-1.
In the process of finalizing the body, simple and inexpensive parts were used:
Aluminum corner 15x15 x 1 mm, bought at HomeCenter.
M3 bolts with a countersunk head, nuts.
Metal spacers with M3 thread.
And this is what we got:
Transformers and filter
Rectifiers
Terminals with coolers
Now it's time for the panels. Because We use a fan for cooling, the air must come out somewhere and come in from somewhere. First of all, I started sawing the back panel with a hole for air outlet:
Everything was done using a drill, jigsaw, engraver and needle files. Now we cut out the grille from the computer power supply case and clean the edges of the hole:
Now we take soldering acid, a soldering iron with a power of at least 100 W and solder the grille to the panel in several places:
We place input and output connectors on the panel, BE SURE TO ISOLATE THEM FROM THE CASE:
Solder the housing shielding lead to the panel. This will be the ONLY point where the chassis connects to the common power wire. We connect the case with the ground contacts of the input connectors through 1-2 W resistors with a nominal value of 1.5-2 Ohms. These measures are needed in order not to catch the “ground loop”, which will spoil us in the form of a 50 Hz background.
Rear panel in place:
Now we transfer the Zobel circuit from the board to the output connectors of the PA. It doesn’t really have a place on the board, because... it (the circuit) is a resonant system:
Now it's up to the front panel. There is only a power switch on it. The panel itself is made of aluminum, behind it there is a false panel made of moderately soft plastic, on which you can fasten anything with M3 screws with countersunk heads. The button was used from an old dead Wilma-104-Stereo cassette deck:
The panel is mounted on tin corners using hex bolts. That's all, the amplifier is ready!
Results
I wrote a comment about sound in the topic about:Guys, I did NOT find out! I didn’t think I’d ever say this, but it’s true! Nice soft bass, distinct highs (now I can distinguish percussion and handclaps on tracks that I know by heart), and all this pleasure on homemade three-way ZY with 8" bass drivers.
I want to reassure everyone who is put off by the increased HF level: to the ear this is not felt as a rise in high frequencies, but as an increase in the quality of the source, an increase in “transparency”.
And I still don’t go back on my words. Over the course of several months, I didn’t get tired of the amplifier at all, as I often do. The sound is not annoying, you want to listen to everything and a lot, no matter at low or high volume.
By the way, about low volume. This ULF has a pleasant feature: at any volume level, the listener does not experience a lack of low frequencies, which can be compared with using a TKRG, only with smooth (correct) adjustment and without midrange blockage.
In my version, the board is slightly redesigned. The choice of “mute” and “standby” modes has been removed as unnecessary, the main capacitor bank has been moved closer to the MS.
Power supply 2×23 V. The rectifier uses KD213B diodes. The electrolytes are shunted with a capacity of 100 nF, the secondary of the transformer is 47 nF.
Each MS is isolated from the radiators by a mica plate, and the radiators, in turn, are grounded to the case.
All wires are twisted together to reduce interference.
The background is not audible even with the input open, even close to the speaker. The goal, so to speak, has been achieved!
Further plans include drilling holes for air intake on the right side of the bottom cover of the case, making a device for adjusting the fan speed with control of the temperature of the radiators, possibly building in a preamplifier with a tone control, and painting the case.
The article is dedicated to lovers of loud and high-quality music. TDA7294 (TDA7293) is a low-frequency amplifier microcircuit manufactured by the French company THOMSON. The circuit contains field-effect transistors, which ensures high sound quality and soft sound. A simple circuit with few additional elements makes the circuit accessible to any radio amateur. A correctly assembled amplifier from serviceable parts begins to work immediately and does not require adjustment.
The audio power amplifier on the TDA 7294 chip differs from other amplifiers of this class:
- high output power,
- wide supply voltage range,
- low percentage of harmonic distortion,
- "soft sound,
- few “attached” parts,
- low cost.
Can be used in amateur radio audio devices, when modifying amplifiers, speaker systems, audio equipment, etc.
The picture below shows typical circuit diagram power amplifier for one channel.
The TDA7294 microcircuit is a powerful operational amplifier, the gain of which is set by a negative feedback circuit connected between its output (pin 14 of the microcircuit) and the inversion input (pin 2 of the microcircuit). The direct signal is supplied to the input (pin 3 of the microcircuit). The circuit consists of resistors R1 and capacitor C1. By changing the values of resistance R1, you can adjust the sensitivity of the amplifier to the parameters of the pre-amplifier.
Block diagram of the amplifier on TDA 7294
Technical characteristics of the TDA7294 chip
Technical characteristics of the TDA7293 chip
Schematic diagram of the amplifier on TDA7294
To assemble this amplifier you will need the following parts:
1. Chip TDA7294 (or TDA7293)
2. Resistors with a power of 0.25 watt
R1 – 680 Ohm
R2, R3, R4 – 22 kOm
R5 – 10 kOhm
R6 – 47 kOhm
R7 – 15 kOhm
3. Film capacitor, polypropylene:
C1 – 0.74 mkF
4. Electrolytic capacitors:
C2, C3, C4 – 22 mkF 50 volt
C5 – 47 mkF 50 volt
5. Double variable resistor - 50 kOm
A mono amplifier can be assembled on one chip. To assemble a stereo amplifier, you need to make two boards. To do this, we multiply all the necessary parts by two, except for the dual variable resistor and power supply. But more on that later.
Amplifier circuit board based on TDA 7294 chip
The circuit elements are mounted on a printed circuit board made of single-sided foil fiberglass.
A similar circuit, but with a few more elements, mainly capacitors. The switch-on delay circuit at the “mute” pin 10 input is enabled. This is done for a soft, pop-free turn on of the amplifier.
A microcircuit is installed on the board, from which unused pins have been removed: 5, 11 and 12. Install using a wire with a cross-section of at least 0.74 mm2. The chip itself must be installed on a radiator with an area of at least 600 cm2. The radiator should not touch the amplifier body in such a way as there will be a negative supply voltage on it. The housing itself must be connected to a common wire.
If you use a smaller radiator area, you need to make forced airflow by placing a fan in the amplifier case. The fan is suitable from a computer with a voltage of 12 volts. The microcircuit itself should be attached to the radiator using heat-conducting paste. Do not connect the radiator to live parts, except for the negative power bus. As mentioned above, the metal plate at the back of the microcircuit is connected to the negative power circuit.
Chips for both channels can be installed on one common radiator.
Power supply for amplifier.
The power supply is a step-down transformer with two windings with a voltage of 25 volts and a current of at least 5 amperes. The voltage on the windings should be the same and so should the filter capacitors. Voltage imbalance should not be allowed. When supplying bipolar power to the amplifier, it must be supplied simultaneously!
It is better to install ultra-fast diodes in the rectifier, but in principle, ordinary ones like D242-246 with a current of at least 10A are also suitable. It is advisable to solder a capacitor with a capacity of 0.01 μF in parallel to each diode. You can also use ready-made diode bridges with the same current parameters.
Filter capacitors C1 and C3 have a capacity of 22,000 microfarads at a voltage of 50 volts, capacitors C2 and C4 have a capacity of 0.1 microfarads.
The supply voltage of 35 volts should only be with a load of 8 ohms; if you have a load of 4 ohms, then the supply voltage must be reduced to 27 volts. In this case, the voltage on the secondary windings of the transformer should be 20 volts.
You can use two identical transformers with a power of 240 watts each. One of them serves to obtain positive voltage, the second - negative. The power of the two transformers is 480 watts, which is quite suitable for an amplifier with an output power of 2 x 100 watts.
Transformers TBS 024 220-24 can be replaced with any others with a power of at least 200 watts each. As written above, the nutrition should be the same - transformers must be the same!!! The voltage on the secondary winding of each transformer is from 24 to 29 volts.
Amplifier circuit increased power on two TDA7294 chips in a bridge circuit.
According to this scheme, for the stereo version you will need four microcircuits.
Amplifier specifications:
- Maximum output power at 8 Ohm load (supply +/- 25V) - 150 W;
- Maximum output power at a load of 16 Ohms (supply +/- 35V) - 170 W;
- Load resistance: 8 - 16 Ohms;
- Coef. harmonic distortion, at max. power 150 watts, e.g. 25V, heating 8 Ohm, frequency 1 kHz - 10%;
- Coef. harmonic distortion, at a power of 10-100 watts, for example. 25V, heating 8 Ohm, frequency 1 kHz - 0.01%;
- Coef. harmonic distortion, at a power of 10-120 watts, for example. 35V, heating 16 Ohm, frequency 1 kHz - 0.006%;
- Frequency range (with a non-frequency response of 1 db) - 50Hz ... 100kHz.
View of the finished amplifier in a wooden case with a transparent plexiglass top cover.
For the amplifier to operate at full power, you need to apply the required signal level to the input of the microcircuit, and this is at least 750 mV. If the signal is not enough, then you need to assemble a pre-amplifier for boosting.
Pre-amplifier circuit on TDA1524A
Setting up the amplifier
A properly assembled amplifier does not need adjustment, but no one guarantees that all parts are absolutely in good working order; you need to be careful when turning it on for the first time.
The first switch-on is carried out without load and with the input signal source turned off (it is better to short-circuit the input with a jumper). It would be nice to include fuses of about 1A in the power circuit (both in the plus and minus between the power source and the amplifier itself). Briefly (~0.5 sec.) Apply the supply voltage and make sure that the current consumed from the source is small - the fuses do not burn out. It is convenient if the source has LED indicators - when disconnected from the network, the LEDs continue to light for at least 20 seconds: the filter capacitors are discharged for a long time by the small quiescent current of the microcircuit.
If the current consumed by the microcircuit is large (more than 300 mA), then there can be many reasons: short circuit in installation; poor contact in the “ground” wire from the source; “plus” and “minus” are confused; the pins of the microcircuit touch the jumper; microcircuit is faulty; capacitors C11, C13 are soldered incorrectly; capacitors C10-C13 are faulty.
Having made sure that everything is normal with the quiescent current, we safely turn on the power and measure the constant voltage at the output. Its value should not exceed +-0.05 V. High voltage indicates problems with C3 (less often with C4), or with the microcircuit. There have been cases when the “ground-to-ground” resistor was either poorly soldered or had a resistance of 3 kOhms instead of 3 ohms. At the same time, the output was constant 10...20 volts. By connecting an AC voltmeter to the output, we make sure that the AC voltage at the output is zero (this is best done with the input closed, or simply with the input cable not connected, otherwise there will be noise at the output). The presence of alternating voltage at the output indicates problems with the microcircuit, or circuits C7R9, C3R3R4, R10. Unfortunately, conventional testers often cannot measure the high-frequency voltage that appears during self-excitation (up to 100 kHz), so it is best to use an oscilloscope here.
All! You can enjoy your favorite music!
In this article I will tell you about a microcircuit such as TDA1514A
Introduction
Let me start with something sad... At the moment, production of the microcircuit has been discontinued... But this does not mean that it is now “worth its weight in gold”, no. You can get it in almost any radio store or radio market for 100 - 500 rubles. Agree, a little expensive, but the price is absolutely fair! By the way, on global Internet sites such as these they are much cheaper...
The microcircuit is characterized by a low level of distortion and a wide range of reproduced frequencies, so it is better to use it on full-range speakers. People who have assembled amplifiers using this chip praise it for its high sound quality. This is one of the few microcircuits that truly “sounds well.” The sound quality is in no way inferior to the currently popular TDA7293/94. However, if errors are made in the assembly, high-quality work is not guaranteed.
Brief description and advantages
This chip is a single-channel Hi-Fi amplifier of class AB, the power of which is 50W. The chip has built-in SOAR protection, thermal protection (overheating protection) and a "Mute" mode.
The advantages include the absence of clicks when turning on and off, the presence of protection, low harmonic and intermodulation distortion, low thermal resistance, and more. There is practically nothing to highlight among the shortcomings, except failure when the voltage “runs” (the power supply must be more or less stable) and the relatively high price
Briefly about appearance
The chip is available in a SIP package with 9 long legs. The pitch of the legs is 2.54mm. On the front side there are inscriptions and a logo, and on the back there is a heat sink - it is connected to the 4th leg, and the 4th leg is the “-” power supply. There are 2 eyelets on the sides for attaching the radiator.
The original or a fake?
Many people ask this question, I will try to answer you.
So. The microcircuit must be carefully made, the legs must be smooth, minor deformation is allowed, since it is unknown how they were handled in a warehouse or store
The inscription... It can be made either with white paint or with a regular laser, the two chips above are for comparison (both are original). If the inscription is painted, there should ALWAYS be a vertical stripe on the chip, separated by an eyelet. Don't be confused by the "TAIWAN" inscription - it's okay, the sound quality of such copies is no worse than those without this inscription. By the way, almost half of the radio components are made in Taiwan and neighboring countries. This inscription is not found on all microcircuits.
I also advise you to pay attention to the second line. If it contains only numbers (there should be 5 of them) - these are “old” production microcircuits. The inscription on them is wider, and the heat sink may also have a different shape. If the inscription on the microcircuit is applied with a laser and the second line contains only 5 digits, there should be a vertical stripe on the microcircuit
The logo on the microcircuit must be present and only “PHILIPS”! As far as I know, production ceased long before NXP was founded, and this is 2006. If you come across this microcircuit with the NXP logo, there is one of two things - they started producing the microcircuit again or it is a typical “leftist”
It is also necessary to have depressions in the shape of circles, as in the photo. If they are not there, it is a fake.
Perhaps there are still ways to identify the “leftist”, but you shouldn’t stress over this issue so much. There are only a few cases of marriage.
Technical characteristics of the microcircuit
* Input impedance and gain are adjusted by external elements
Below is a table of approximate output powers depending on power supply and load resistance
| Supply voltage | Load resistance | ||
| 4 ohm | 8 ohm | ||
| 10W | 6W | ||
| +-16.5V |
28W |
12W | |
| 48W | 28W | ||
| 58W | 32W | ||
| 69W | 40W | ||
Schematic diagram
The diagram is taken from the datasheet (May 1992)
It's too bulky... I had to redraw it:
The circuit differs slightly from that provided by the manufacturer, all the characteristics given above are exactly for THIS circuit. There are several differences and they are all aimed at improving the sound - first of all, filter capacitors were installed, the “voltage boost” was removed (more on that a little later) and the value of resistor R6 was changed.
Now in more detail about each component. C1 is the input coupling capacitor. It passes through only the alternating voltage signal. It also affects the frequency response - the smaller the capacitance, the smaller the bass and, accordingly, the larger the capacitance, the greater the bass. I would not recommend setting it to more than 4.7 µF, since the manufacturer has provided for everything - with the capacitance of this capacitor equal to 1 µF, the amplifier reproduces the declared frequencies. Use a film capacitor, in extreme cases an electrolytic one (non-polar is desirable), but not a ceramic one! R1 reduces the input resistance, and together with C2 forms a filter against input noise.
As with any operational amplifier, the gain can be set here. This is done using R2 and R7. At these ratings, the gain is 30 dB (may deviate slightly). C4 affects the activation of SOAR and Mute protection, R5 affects the smooth charging and discharging of the capacitor, and therefore there are no clicks when the amplifier is turned on and off. C5 and R6 form the so-called Zobel chain. Its task is to prevent the amplifier from self-excitation, as well as to stabilize the frequency response. C6-C10 suppress power supply ripples and protect against voltage sags.
The resistors in this circuit can be taken with any power, for example I use the standard 0.25W. Capacitors for a voltage of at least 35V, except for C10 - I use 100V in my circuit, although 63V should be enough. All components must be checked for serviceability before soldering!
Amplifier circuit with "voltage boost"
This version of the circuit is taken from the datasheet. It differs from the above-described scheme in the presence of elements C3, R3 and R4.
This option will allow you to get up to 4W more than stated (at ±23V). But with this inclusion, distortion may increase slightly. Resistors R3 and R4 should be used at 0.25W. I couldn’t handle it at 0.125W. Capacitor C3 - 35V and above.
This circuit requires the use of two microcircuits. One gives a positive signal at the output, the other a negative one. With this connection, you can remove more than 100W into 8 ohms.
According to those who gathered, this scheme is absolutely workable and I even have a more detailed table of approximate output powers. It's below:
And if you experiment, for example, at ±23V you connect a 4 ohm load, you can get up to 200W! Provided that the radiators do not heat up too much, the 150W microcircuit will be easily pulled into the bridge.
This design is good to use in subwoofers.
Operation with external output transistors
The microcircuit is essentially a powerful operational amplifier and it can be further boosted by adding a pair of complementary transistors to the output. This option has not yet been tested, but it is theoretically possible. You can also power up the bridge circuit of the amplifier by attaching a pair of complementary transistors to the output of each microcircuit
Operation with unipolar power supply
At the very beginning of the datasheet, I found lines that say that the microcircuit also works with single-supply power. Where is the diagram then? Alas, it’s not in the datasheet, I couldn’t find it on the Internet... I don’t know, maybe such a circuit exists somewhere, but I haven’t seen one... The only thing I can recommend is TDA1512 or TDA1520. The sound is excellent, but they are powered from a single-polar supply, and the output capacitor can slightly spoil the picture. Finding them is quite problematic; they were produced a very long time ago and were discontinued a long time ago. The inscriptions on them can be of various shapes; there is no need to check them for “fake” - there have been no cases of refusal.
Both microcircuits are Hi-Fi class AB amplifiers. Power is about 20W at +33V into a 4 ohm load. I won’t give the diagrams (the topic is still about the TDA1514A). You can download printed circuit boards for them at the end of the article.
Nutrition
For stable operation of the microcircuit, you need a power source with a voltage from ±8 to ±30V with a current of at least 1.5A. Power must be supplied with thick wires, the input wires should be kept as far away from the output wires and the power source as possible
You can power it with an ordinary simple power supply, which includes a mains transformer, a diode bridge, filter tanks and, if desired, chokes. To obtain ±24V, you need a transformer with two 18V secondary windings with a current of more than 1.5A for one microcircuit.
You can use switching power supplies, for example the simplest one, on IR2153. Here is his diagram:
This UPS is made using a half-bridge circuit, frequency 47 kHz (set using R4 and C4). Diodes VD3-VD6 ultrafast or Schottky
It is possible to use this amplifier in a car using a boost converter. On the same IR2153, here is the diagram:
The converter is made according to the Push-Pull scheme. Frequency 47kHz. Rectifier diodes need ultrafast or Schottky ones. Transformer calculations can also be performed in ExcellentIT. The chokes in both schemes will be “recommended” by ExcellentIT itself. You need to count them in the Drossel program. The author of the program is the same -
I would like to say a few words about the IR2153 - the power supplies and converters are quite good, but the microcircuit does not provide stabilization of the output voltage and therefore it will change depending on the supply voltage, and it will also sag.
It is not necessary to use IR2153 or switching power supplies in general. You can do it simpler - like in the old days, a regular transformer with a diode bridge and huge power supply capacities. This is what its diagram looks like:
C1 and C4 at least 4700 µF, for a voltage of at least 35V. C2 and C3 - ceramics or film.
Printed circuit boards
Now I have the following collection of boards:
a) the main one - it can be seen in the photo below.
b) slightly modified first (main). All tracks have been increased in width, the power ones are much wider, the elements have been slightly moved.
c) bridge circuit. The board is not drawn very well, but it is functional
d) the first version of the PP is the first trial version, there is not enough Zobel chain, but I assembled it this way and it works. There is even a photo (below)
d) printed circuit board fromXandR_man - found it on the forum of the Soldering Iron site. What can I say... Strictly a diagram from the datasheet. Moreover, I saw with my own eyes sets based on this signet!
In addition, you can draw the board yourself if you are not satisfied with the ones provided.
Soldering
After you have made the board and checked all the parts for serviceability, you can start soldering.
Tin the entire board, and tin the power traces with as thick a layer of solder as possible
All jumpers are soldered in first (their thickness should be as large as possible in the power sections), and then all components increase in size. The microcircuit is soldered last. I advise you not to cut the legs, but solder them as they are. You can then bend it to make it easier to fit on the radiator.
The microcircuit is protected from static electricity, so you can solder with the soldering iron turned on, even while sitting in woolen clothes.
However, it is necessary to solder so that the chip does not overheat. For reliability, you can attach it to the radiator by one eye during soldering. You can do it in two, there won’t be any difference, as long as the crystal inside doesn’t overheat.
Setup and first launch
After all the elements and wires are soldered, a “test run” is necessary. Screw the microcircuit onto the radiator and connect the input wire to ground. You can connect future speakers as a load, but in general, to prevent them from “flying out” in a split second due to defects or installation errors, use a powerful resistor as a load. If it crashes, you know that you made a mistake, or you got a defect (the microcircuit is meant). Fortunately, such cases almost never happen, unlike TDA7293 and others, of which you can get a bunch of them from one batch in a store and, as it turns out later, they are all defective.
However, I want to make a small note. Keep your wires as short as possible. It happened that I just lengthened the output wires and began to hear a hum in the speakers, similar to “constant”. Moreover, when the amplifier was turned on, due to the “constant” mode, the speaker produced a hum that disappeared after 1-2 seconds. Now I have wires coming out of the board, a maximum of 25 cm and going straight to the speaker - the amplifier turns on silently and works without problems! Also pay attention to the input wires - use a shielded wire; it shouldn’t be long either. Follow simple requirements and you will succeed!
If nothing happened to the resistor, turn off the power, attach the input wires to the signal source, connect your speakers and apply power. You can hear a slight hum in the speakers - this indicates that the amplifier is working! Give a signal and enjoy the sound (if everything is perfectly assembled). If it “grunts” or “farts” - look at the food, at the correctness of assembly, because, as has been discovered in practice, there are no such “nasty” specimens that, with proper assembly and excellent nutrition, worked crookedly...
What the finished amplifier looks like
Here is a series of photographs taken in December 2012. The boards are just after soldering. Then I assembled it to make sure the microcircuits were working.
But my first amplifier, only the board has survived to this day, all the parts went to other circuits, and the microcircuit itself failed due to alternating voltage coming into contact with it
Below are the latest photos:
Unfortunately, my UPS is at the manufacturing stage, and I previously powered the microcircuit from two identical batteries and a small transformer with a diode bridge and small power supply capacities, in the end it was±25V. Two such microcircuits with four speakers from the Sharp music center played so well that even the objects on the tables “danced to the music,” the windows rang, and the body felt the power quite well. I can’t remove this now, but there is a ±16V power supply, from it you can get up to 20W at 4 ohms... Here is a video for you as proof that the amplifier is absolutely working!
Acknowledgments
I express my deep gratitude to the users of the “Soldering Iron” site forum, and specifically, a huge thank you to the user for some help, and I also thank many others (sorry for not calling you by nickname) for their honest feedback, which pushed me to build this amplifier. Without all of you, this article might not have been written.
Completion
The microcircuit has a number of advantages, first of all, excellent sound. Many microcircuits of this class may even be inferior in sound quality, but this depends on the quality of the assembly. Bad assembly - bad sound. Take electronic circuit assembly seriously. I strongly do not recommend soldering this amplifier by surface mounting - this can only worsen the sound, or lead to self-excitation, and subsequently complete failure.
I collected almost all the information that I checked myself and could ask other people who assembled this amplifier. It's a pity that I don't have an oscilloscope - without it, my statements about sound quality mean nothing... But I will continue to say that it sounds just great! Those who collected this amplifier will understand me!
If you have any questions, write to me on the forum of the Soldering Iron site. to discuss amplifiers on this chip, you can ask there.
I hope the article was useful to you. Good luck to you! Regards, Yuri.
List of radioelements
| Designation | Type | Denomination | Quantity | Note | Shop | My notepad | |
|---|---|---|---|---|---|---|---|
| Chip | TDA1514A | 1 | To notepad | ||||
| C1 | Capacitor | 1 µF | 1 | To notepad | |||
| C2 | Capacitor | 220 pF | 1 | To notepad | |||
| C4 | 3.3uF | 1 | To notepad | ||||
| C5 | Capacitor | 22 nF | 1 | To notepad | |||
| C6, C8 | Electrolytic capacitor | 1000uF | 2 | To notepad | |||
| S7, S9 | Capacitor | 470 nF | 2 | To notepad | |||
| C10 | Electrolytic capacitor | 100uF | 1 | 100V | To notepad | ||
| R1 | Resistor | 20 kOhm | 1 | To notepad | |||
| R2 | Resistor | 680 Ohm | 1 | To notepad | |||
| R5 | Resistor | 470 kOhm | 1 | To notepad | |||
| R6 | Resistor | 10 ohm | 1 | Selected during setup | To notepad | ||
| R7 | Resistor | 22 kOhm | 1 | To notepad | |||
| Circuit with voltage boost | |||||||
| Chip | TDA1514A | 1 | To notepad | ||||
| C1 | Capacitor | 1 µF | 1 | To notepad | |||
| C2 | Capacitor | 220 pF | 1 | To notepad | |||
| C3 | Electrolytic capacitor | 220uF | 1 | From 35V and above | To notepad | ||
| C4 | Electrolytic capacitor | 3.3uF | 1 | To notepad | |||
| C5 | Capacitor | 22 nF | 1 | To notepad | |||
| C6, C8 | Electrolytic capacitor | 1000uF | 2 | To notepad | |||
| S7, S9 | Capacitor | 470 nF | 2 | To notepad | |||
| C10 | Electrolytic capacitor | 100uF | 1 | 100V | To notepad | ||
| R1 | Resistor | 20 kOhm | 1 | To notepad | |||
| R2 | Resistor | 680 Ohm | 1 | To notepad | |||
| R3 | Resistor | 47 Ohm | 1 | Selected during setup | To notepad | ||
| R4 | Resistor | 82 Ohm | 1 | Selected during setup | To notepad | ||
| R5 | Resistor | 470 kOhm | 1 | To notepad | |||
| R6 | Resistor | 10 ohm | 1 | Selected during setup | To notepad | ||
| R7 | Resistor | 22 kOhm | 1 | To notepad | |||
| Bridge connection | |||||||
| Chip | TDA1514A | 2 | To notepad | ||||
| C1 | Capacitor | 1 µF | 1 | To notepad | |||
| C2 | Capacitor | 220 pF | 1 | To notepad | |||
| C4 | Electrolytic capacitor | 3.3uF | 1 | To notepad | |||
| C5, C14, C16 | Capacitor | 22 nF | 3 | To notepad | |||
| C6, C8 | Electrolytic capacitor | 1000uF | 2 | To notepad | |||
| S7, S9 | Capacitor | 470 nF | 2 | To notepad | |||
| C13, C15 | Electrolytic capacitor | 3.3uF | 2 | To notepad | |||
| R1, R7 | Resistor | 20 kOhm | 2 | To notepad | |||
| R2, R8 | Resistor | 680 Ohm | 2 | To notepad | |||
| R5, R9 | Resistor | 470 kOhm | 2 | To notepad | |||
| R6, R10 | Resistor | 10 ohm | 2 | Selected during setup | To notepad | ||
| R11 | Resistor | 1.3 kOhm | 1 | To notepad | |||
| R12, R13 | Resistor | 22 kOhm | 2 | To notepad | |||
| Impulse power block | |||||||
| IC1 | Power Driver and MOSFET | IR2153 | 1 | To notepad | |||
| VT1, VT2 | MOSFET transistor | IRF740 | 2 | To notepad | |||
| VD1, VD2 | Rectifier diode | SF18 | 2 | To notepad | |||
| VD3-VD6 | Diode | Any Schottky | 4 | Ultrafast diodes or Schottky | To notepad | ||
| VDS1 | Diode bridge | 1 | Diode bridge for the required current | To notepad | |||
| C1, C2 | Electrolytic capacitor | 680uF | 2 | 200V | To notepad | ||
| C3 | Capacitor | 10 nF | 1 | 400V | To notepad | ||
| C4 | Capacitor | 1000 pF | 1 | To notepad | |||
| C5 | Electrolytic capacitor | 100uF | 1 | To notepad | |||
| C6 | Capacitor | 470 nF | 1 | To notepad | |||
| C7 | Capacitor | 1 nF | 1 | ||||
