TDA2030A single-supply high-power amplifier

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Noobs are like hungry watts mungers as long as the words easy , simple , cheap are used together with high *00 watts they go mad
so do i as i am a noob
well can the experts post a correct working pcb so we noobz can do it right
i also have interest in that tda 7294 Plus transistors amp so who will the noobz listen to here
the guy with a working amp or ppl who just saying it can't work
how about the experts jump in and correct it so us noobz can build working items and not waste money and time an losing interest

Understandable.

Power ratings for amplifiers that are commercial products, in the USA, are required to have their power ratings measured and advertised in a certain way. Basically, they must advertise the continuous RMS power that one sine wave would produce, at below the clipping level.

The maximum possible continuous RMS output power is totally limited by the supply voltage, or the supply current, for a given speaker resistance rating. So if you know either the maximum supply voltage, or the maximum supply current, and the speaker resistance rating, you can immediately calculate the maximum POSSIBLE output power, in terms of both peak Watts and RMS Watts. There is basically no way around it.

Ignoring for the moment that the input power supply voltage would need to have subtracted from it: the ripple voltage and the amplifier dropout voltage, and a diode voltage drop or two if it's an AC power input, lt's assume that an amplifier has plus and minus 40 Volts DC to work off of (most amps are powered by both positive and negative voltages), and won't clip at that voltage. So for now we're saying that the output can swing to +40 and -40. [With only one supply, + or - but not both, just cut the following numbers in half.]

First, you have to find the maximum RMS sine output voltage, by dividing by 1.414. SO that's 40 / 1.414 = 28.2 Volts RMS.

Then, use the formula for RMS power: Watts RMS = Vrms x Vrms / R_speaker.

So for an 8-Ohm speaker, that would be 28.2 x 28.2 / 8 = 99.4 Watts RMS (actually, it's 100 Watts RMS, but I rounded-off the square root of two to 1.414).

With 40 Volts, it would be literally IMPOSSIBLE to get a higher continuous RMS power output level into 8 Ohms.

And, for 4 Ohms, 2 Ohms, 1 Ohm, it would be higher (2x, 4x, and 8x higher).

PEAK power is calculated the same way, except you just start with the peak voltage, instead of the RMS voltage. It turns out that the maximum possible peak power is always exactly 2X the maximum RMS power:

Watts peak = Vpeak x Vpeak / R_speaker

= 40 x 40 / 8 = 200 Watts peak.

As far as the present discussion is concerned, there is NO WAY to get more than that, with a 40V DC supply and an 8-Ohm load.

But, lo and behold, with 2 Ohms, that would be 800 Watts peak.

But, of course, from that 40 Volts, in reality, you have to subtract at least the ripple voltage and the amp's dropout voltage. Even with monster capacitors that make the ripple voltage really small, there's no way around the dropout or "clipping" voltage, which might typically be 3 to 4 volts. So, for +/-40 Volts DC in, you would only be able to get something like 36 or 37 Volt peaks, at the output, at the very most. So you would calculate the maximum power with one of those, or the actual maximum output voltage swing.
 
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The arithmetic is so simple that any school child can check adverts to see if the retailer is telling lies.

Don't automatically believe all you read/see. Analyse, at least to the most basic levels, to determine whether you want to use the information in a real life situation.
 
2cents

Numbers will work on bench for this IC and circuit ( bench= 1KHZ @ resistive load 4-8R ) but never in real life since real life speakers are inductive loads and internal limiting of the IC will behave accordingly .

Still if you take a closer look you will see that this is also a form of sziklai style circuit which will produce nice sonics and harmonics only up to the quality of the IC ,and prove to be extremely tolerant to even demanding types of music or speakers or long cables .

To be more specific external transistor will bother with the current demands while the Ic will play the music

Kind regards
Sakis
 
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ok
so the ic plays the music and the transistor adds a lil more current to it
i notice that while i was looking at the diagram the music signal never flow through the transistors
hmmm is there way to make it so the sound passes through the transistors
while i was researchin amps i came across some small amp build diagrams i will post it when i get some time
 
ok
so the ic plays the music and the transistor adds a lil more current to it
i notice that while i was looking at the diagram the music signal never flow through the transistors
hmmm is there way to make it so the sound passes through the transistors
while i was researchin amps i came across some small amp build diagrams i will post it when i get some time


Then in this case skip the all project and go for a real amplifier like the DX amplifier or P3A or sixtek amp and you get your shelf a real amp from both aspects IE quality of sound and power .

for the specific circuit and given the nature of the IC i see no other way to handle the external transistors but may others come with a better idea ... EFP them will need bias and other things

Kind regards
sakis ...
 
OK, build and test it, it will be fun :)
Stiff 24VDC? (you mentioned truck batteries): best case 19Vpp which divided by 2.8 yield 6.8V RMS= *almost* 6W RMS into 8 ohms or 12W RMS into 4 .

Just as a side note, adding the extra transistors adds nothing to power; such supply and loads are well within the unaided chip capabilities
 
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ok ok
so this voltage does not bring in the transistors in effect ok ok
so what voltage will do this will give me maximum effect
No, it isn't that this voltage does not bring in the transistors in effect
, but
a) you won't have more peak voltage than your PSU allows.
b) they won't supply more current than your PSU allows and your load demands.
which in good English means:
they are not doing anything useful.

Not forgetting that *you* specified 24V PSU.:D
 
lol yeah i know 24v is the voltage on the truck but when you start it the volt goes up to 28v so it swings from 24-28
hmm i am just asking so beginner questions
1, what if i add sum caps in parallel say 6 2200uf 35v to the power line before the input voltage stage of the amp will help boost the voltage up
also buy adding sumthing to only have that voltage flow 1 direction so it don't go back to the source
will it work what is a easy cheap way to do it
 
frogq,
Capacitors won't raise the voltage the way you're thinking. If a capacitor is rated at 35V, that's the maximum voltage it's designed to withstand before failing--it won't raise a lower voltage to 35V.
Blocking the voltage flow will simply turn it off--nothing will flow.

If you want to raise the voltage, then you will need a DC-DC power supply. It would be a complicated project by itself.
 
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