[Click the image to enlarge it]
- Electronics Projects, 20W Stereo Amplifier With TDA2003 Tone Control ' audio amplifier circuits, audio control circuits, ic amplifier, ' Date 2019/08/04 Many times we have been asked about an amplifier that can be powered with the computer source to amplify this.
- TDA2003 is a cheap amplifier that is designed to run on single rail power supplies (unipolar). It provides a high output current capability (up to 3.5A), very low harmonic and cross-over distortion. TDA2003 10W car radio audio amplifier.
TDA2003 Stereo Amplifier Design Tutorial The PCB and schematic project files: The TDA2003 is a.
The TDA2003 is an Audio Amplifier IC from ST Microelectronics with a maximum output power of 10W commonly used in stereo amplification in car Radio. The IC can output a maximum current of 3.5A and features very low harmonic and crossover distortion.
Pin Description
Pin Number | Pin Name | Description |
1 | Non – Inverting Input | Non inverting end (+) of Amplifier |
2 | Inverting Input | Inverting end (-) of Amplifier |
3 | Ground | Connect to the ground of the circuit |
4 | Output | This pin outputs the amplified signal |
5 | Supply Voltage | Supply voltage, Minimum 6V and Maximum 36V |
Features
- Low-frequency class AB amplifier most suited for audio amplification
- Can provide up to 20 Watts as output power
- Operating Voltage: 8V to 18V
- Maximum output power 12V (at 1.6Ω RL)
- Voltage Gain: 80dB
- Supply Voltage rejection: 36dB
- Short circuit and thermal protection is available
- Breadboard friendly
- Available in 5-pin TO220 package
Note: Complete Technical Details can be found at the datasheet give at the end of this page.
Alternative to TDA2003: TDA2009
Other Audio Amplifiers: LM386, TDA1554, TDA2030, TDA7294, TDA7265, TDA7279, TDA2005
Introduction to TDA2003
TDA2003 is a general-purpose 10W amplifier IC that can be used in stereo or mono audio design circuits. The amplifier can output upto 3.5A current to drive speakers and can also handle high current upto 5A for shorter duration without any damage. It can also handle short circuits in both AC and DC rail without killing itself. It has an operating voltage of 18V but can handle high voltage up to 28V. This makes it robust to be used in automotive audio designs.
The TDA2030 is breadboard friendly and hence can be easily tested using a breadboard. A sample application circuit for TDA2030 is given below. The datasheet given at the bottom of this page consists of more details on this design.
TDA2003 is a 5-pin Amplifier IC. The pin 5 and 3 are used to power the Amplifier IC, and the audio signal to be amplified is given in through pin 1 which is the non-inverting input. The amplified audio output can be obtained through pin 4. The values of the components given above are the values recommended by manufactures. The two important components are the Cx and Rx which sets the bandwidth for the amplifier using the formulae shown above. Also the Resistors R1 and R2 are used doe setting the gain of the amplifier.
Applications
- Used for Audio signal Amplification
- Suitable for high power amplification
- Capable of operating on dual/split power supply
- Can be used to cascade audio speakers
2-D Model (PDIP)
Recommended Experience : lower intermediate, knowledge of amplifiers, PCB etching, heatsink attaching, and (optional) mains qualification
TDA2003 application
Quick facts TDA2003 / TDA2003A
- Power output: 6W into 4 ohms at 10% 1kHz distortion with power supply 14.4V
- Power output: 10W into 2 ohms at 10% 1kHz distortion with power supply 14.4V
- Power output: 4.5W into 4 ohms at 0.15% 1kHz distortion with power supply 14.4V
- Power output: 7.5W into 2 ohms at 0.15% 1kHz distortion with power supply 14.4V
- Gain: 40dB, adjustable, but with consequences
- Power supply: 8V to 18V single supply
Guide
Warning: These chips have been discontinued and are susceptible to fakes. If you're buying, make sure it is from a good supplier (i.e. not auction sites) to get the genuine chip otherwise performance will be bad, the chip may be easily damaged and create a hazard, or hum/buzz may be worse than the official chip.
The TDA2003 is a cheap amplifier that is designed to run on single rail power supplies. It has many applications (including in car systems if you do not need to show off down the high street with your high power subwoofers!) and is protected against short circuits in almost every way you would think them possible.
It is a mono amplifier, but the TDA2009 is a stereo version alternative (not covered here).
Here are some applications it would be happy to work as:
- A pair can form a capable amp for a stereo system (i.e. a homemade or upgraded midi system or 'ghetto-Blaster', although battery operation may not be the best).
- This amplifier can be used to complete small surround sound systems (i.e. centre and rear channel amps).
- A pair can be used to improve the sound from a TV.
- Beefing up those 400W+ amps in PC speakers (seriously)!
- Tweeter or mid-range amplifiers in bi-amp or tri-amp systems.
- Bluetooth speakers.
- Music instruments i.e. Keyboard, Theremin.
This amplifier is based on the typical application in the ST Microelectronics datasheet. The performance from this circuit is satisfactory. The sheet contains data for typical noise and distortion statistics, I cannot confirm these statistics because I don't have the equipment, but my ears tell me that the sound is good and with sensitive speakers, this amp will show some power, but its power output isn't amazing. Output power into 8 ohms isn't shown anywhere, but expect it to be small!
For best power, I suggest the bridge circuit is used. This needs two TDA2003 chips and more components, but doesn't need that 1000uF (or higher) output capacitor which is costly and reduces bass.
The circuit is very simple, as can be seen, however you will have problems with Veroboard / Stripboard mounting due to its pin layout. It is possible, but you will find this amp A LOT easier to build on a PCB. The PCB layout suggestion in the original datasheet is a mistake copy of the bridge version, so don't use that, however a more up to date TDA2003A datasheet does have the correct layout, but note that C3 (the 100uF) bypass capacitor is not included. I suggest extending the board further right and locating C3 to the right of C5. It needs to go from +Vs to ground.
Note: The above image is copied directly from the datasheet and is not mine, nor is it likely to be 1:1 scale. To achieve this scale, the best idea is to print to PDF file to A4 paper. Please use the datasheet to view the schematic and the component values.
If you must use stripboard however, this is how I would mount them. First straighten all the pins, then cut them to the length of the shortest two. Now you need to spread them out so they will fit into the stripboard. Do not spread them too much or they will break and your TDA2003 chip becomes useless.
Resistor are recommended as 1% metal film, but as the picture of my prototype shows below, 5% resistors are capable, except for the critical Rx resistor, which should be 1%. R2 and R3 are low value resistors and you should try and get close tolerance resistors for these. Capacitors should be electrolytic above 1uF and rated at 25V minimum. They must all be connected the right way round or failure and possibly injury will follow when the amp is powered up.
The gain is set by R1 and R2, which is 1+(R1/R2) in gain voltage. Using the default values in the datasheet that is 1+(220/2.2) giving a gain voltage of 101. In decibels, that is 20*log(101) coming to 40dB. That's a very high gain! At this gain, a 50mV RMS signal will output 6W into 4 ohms, which is pretty much its maximum power. It means this chip is unlikely to need a preamp and is probably intended to be hooked directly to an FM output or tape output.
Tda2003 Pcb Diagram
Reducing R1 will reduce the gain. To get it to a more standard 30dB, R1 needs to be reduced to 68 ohms. That's a really low value for a feedback resistor though and drain current will be increased. Alternately we can raise the value of R2 above 2.2 ohm, however this degrades supply voltage rejection (SVR).
A reasonable compromise would be to reduce/increase both to say 150 ohm for R1 and 4.7 ohm for R2. This gives a gain 30.3dB.
Rx and Cx are needed for stability and must be worked out using the data sheets mathematical calculations. Calculate Rx first which is 20 times R2, giving 44 ohms (39 ohms is the closest). Cx is 1 / (2 * π * B * R1) where B is the frequency cut off and R1 is 220 ohm by default. Using 20Hz; 1 / (2 * π * 20000 * 220) gives 0.000000033 - that's 33 nano farads (nF).
If you went with less gain and picked 150 ohm for R1, 4.7 ohm for R2, then Rx/Cx will be different. Rx would be 20 * 4.7 = 94 ohm (pick 100 ohm) and Cx would be 1 / (2 * π * 20000 * 150) = 49nF (pick 47nF).
Other non-electrolytic capacitors can be any type available. I used polyester layer capacitors because they have a closer tolerance (i.e. 5%) than most other capacitors.
For C3 (bypass capacitor) and C5 (Zobel capacitor) - these should be ceramic or multi-layer ceramic (MLCC) capacitors
A heatsink is important. The one shown in my prototype is actually too small and you should obtain something bigger for improved operation.
Power Supply
12V single supply power supplies are plentiful, and 16V can also be found which will give more power. I don't recommend going higher than this. You can purchase a great deal of 12V to 16V external power supplies that will happily provide the TDA2003 what it needs. Make sure they are rated for audio or video, otherwise noise and ringing will be heard through the amplifier. Laptop PSUs work well, but unsure their voltage isn't too high. The output should be at least 30W, meaning a 2A output minimum would be fine. Double this for a stereo amplifier, or bridged amplifier. Quadruple it for a stereo bridged amplifier (i.e. 4x TDA2003s)!
Alternative, you can build your own PSU, but before wiring a power supply, take note of this:
THE POWER SUPPLY REQUIRES MAINS VOLTAGE WIRING. DO NOT WIRE IT UNLESS YOU ARE SUITABLE QUALIFIED, DEATH OR SERIOUS INJURY MAY RESULT.
If in doubt, do not wire your own transformer and get a pre-built one. The power supply is simple to wire and my prototype board already has it wired in. You cannot see the bridge rectifier because it is hidden behind the huge 4700uF 35V capacitor. You can see that I added an LED though, this is easy to do and needs 1.2k resistor, 5% tolerance is fine.
Tda2003 Pcb Layout
The transformer should not be rated above 12V AC. This will give a 17V DC output (give or take) unregulated.
You could get away with a small transformer such as around 30VA with 2-wire AC outputs, for one amplifier. Double that for a stereo pair, or mono bridged amplifier, and so on.
The components on the earth and ground connections form a loop breaker. This is recommended construction because it can eliminate those evil earth loops. R1 is a 5W or better wire-wound resistor. The 100nF capacitor must be rated for 250V AC, you cannot use a 250V DC cap as it would fail if there ever was a fault causing mains to flow to earth. Check your country's rules and regulations before constructing this as it may be illegal. If so, omit all these components and connect the earth to ground but never disconnect the earth lead... it could save your life or somebody elses!
Bridge Versions
There are two bridge versions available in the ST data sheet. A 20W version is below and performance from this circuit should be good.
The benefit of the bridge version is you'll get double the output for not much extra space and cost. The large capacitor on the single chip version (C4), required to block the DC current flowing through the speaker is no longer needed (as both sides of the speaker now have the same DC voltage, hence no current flows).
The circuit is a bit more complex, but should not pose any great layouts challenges. Again, PCBs are recommended as there are now two TDA2003 chips.
An alternative is the low-cost bridge amplifier which has a smaller component count and an output power of 18W. All you need is several 0.1uF caps, plus a 1nF and a 10uF electrolytic. Put in one resistor, and there you have it. I must add though that a did try wiring this circuit years ago on stripboard and the amp refused to work. You may have more luck than me but it would be more comforting if you used PCB instead, especially as the ST Microelectronics datasheet does contain a very nice stereo layout for it as shown below:
Note: The above image is copied directly from the datasheet and is not mine, nor is it likely to be 1:1 scale. To achieve this scale, the best idea is to print to PDF file to A4 paper. Please use the datasheet to view the schematic and the component values.
For the bridged version, do not go for loads lower than 4 ohms (this includes two 8 ohm loads in parallel) and do not short the loudspeaker to ground.
Performance and Prototype Photo:
My prototype works well. This board not only includes the amp, but its power supply and a very simple passive crossover (that's the axial electrolytic you can see bottom left). This allows a woofer and tweeter to be added with ease in the proposed system. You may notice the pins on the TDA2003 chip. They are spread out like they have to be when stripboard mounting. This is because this chip was used on my stripboard bridge version that failed.
Inputs are also on the left and the AC is the green and white wires appearing at the back. You can also see an LED at the front, this was to ensure me that everything in the supply was fine. The large 4700uF and 1000uF capacitors hide a few of the components.
The sound is quite impressive, with response across the audio spectrum. This amp will not go very loud though, turn it up and it will clip. I would expect better performance from the bridge versions, I am proposing to build one and will update this page with its performance. The bridge version (especially the low cost one) may actually beat the TDA2040 on price, but that depends on your supplier.