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Give me a 5w or 10w amplifier circuit

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abdulmakhdoom

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post the 3w or 5w or 10w amplifier circuit from 5v source.
 

Is your load a typical 4 ohm speaker?

Then with a 5V single polarity supply...
you can use a full H-bridge to get 3W, by careful adjustments to optimize performance.

Or, if the supply is bipolar +5 -5 V...
then a class AB can easily yield 3W output.
 

post the 3w or 5w or 10w amplifier circuit from 5v source.

imo a power source of only 5v implies that your pk-pk voltage swing is max 5v.
This implies a Vrms of just 1.768v

Hence to derive even 3W, we need a load (spkr) impedance of < 1.768^2 / 3 = ~1 ohm !!

Or am i missing something ?
 

If 3w is not possible for +5v source then please give me the info of 1 or 2w amplifier circuit with +5V source.
 

This is a very simple H-bridge audio amplifier.



With a 5V supply, it can deliver over 9V peak-to-peak (if the incoming waveform has sufficient amplitude).

It wastes over 300 mA when there is no signal. It will take some additional circuitry to remedy this.
 
Hi
I've designed this circuit for handling out put power , of 20Watts ( something around it ! ) . take a look here , please :


It's input also can be a microphone ! or everything that you're interested in ! for changing the out put voice amplitude you can easily add a potentiometer in your input or perhaps instead of gain control resistors .
Best Wishes
Goldsmith
 

This is a very simple H-bridge audio amplifier.

With a 5V supply, it can deliver over 9V peak-to-peak (if the incoming waveform has sufficient amplitude).

It wastes over 300 mA when there is no signal. It will take some additional circuitry to remedy this.

Ah yes - good one Brad. I forgot about the voltage doubling effect of the H-bridge config. This would give around 2.5Wrms into 4ohm spkrs/ 5w into 2ohms, with some improvements in the biasing arrangement.

How about a class-D config driving a H-bridge - for better efficiency ?

- - - Updated - - -

Hi
I've designed this circuit for handling out put power , of 20Watts ( something around it ! ) .......

This doesn't work off +5v... its using a +/- 15v power source !!
 
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Originally Posted by rohitkhanna
...
How about a class-D config driving a H-bridge - for better efficiency ?

Yes, class D consists of pulses that go from supply rail to supply rail.
It will be able to get the most out of the 5V supply.
If it is done with an H-bridge, it could make use of the entire 10V.

It so happens that Goldsmith is able to help with information about class D amplifiers.
 

This doesn't work off +5v... its using a +/- 15v power source !!
Hi rohitkhanna
Why you think the circuit should work with 5 volts ? what is the benefit of a 5 volts supply ? . the original poster didn't mention the supply rating before .
And another point is you can decrease supply voltage of my circuit too ! so that's not a problem .
How about a class-D config driving a H-bridge - for better efficiency ?
A question , why for such a low power , rating we should design a class D amplifier ? that's not economic for 10 watts !
However it has pretty low THD and much better efficiency but i think price is important !
By the way , the circuit that has been presented by Bradtherad is a good idea too . ( for this range of power his circuit or my circuit in my former post are both fine )
Regards
Goldsmith
 

Hi rohitkhanna
Why you think the circuit should work with 5 volts ? what is the benefit of a 5 volts supply ? . the original poster didn't mention the supply rating before .
Read post#1 again please.

And another point is you can decrease supply voltage of my circuit too ! so that's not a problem .

Your circuit uses TL072 which are not rated for supply voltages below 7v, so it will not work with 5v. Secondly, even if you found opamps to work at sub-5v supply, your biasing scheme for output bjt's will need modifications. Lastly, your design works using split supply - while we are discussing single supply options.

A question , why for such a low power , rating we should design a class D amplifier ? that's not economic for 10 watts !
However it has pretty low THD and much better efficiency but i think price is important !

Because the OP asked for +5v supply & 3/5/10 watts operation.
 

Hi again
Read post#1 again please.
Yes you're absolutely right . i didn't see the end of his sentence and it is very fun ! ha ha !
Your circuit uses TL072 which are not rated for supply voltages below 7v, so it will not work with 5v. Secondly, even if you found opamps to work at sub-5v supply, your biasing scheme for output bjt's will need modifications. Lastly, your design works using split supply - while we are discussing single supply options.
Again You're quite right . but it is not a problem ! because he/she can use a push pull amplifier to increase the out put voltage with taking more current ! so main supply can be 5 volts but out put voltage can be higher !
Because the OP asked for +5v supply & 3/5/10 watts operation.
I hope you know about limitations of a Class D amplifier . there are gang of reasons that why a class D amplifier isn't good choice with 5 volts supply !
Regards
Goldsmith
 

.....use a push pull amplifier to increase the out put voltage with taking more current ! so main supply can be 5 volts but out put voltage can be higher ! ...

This is precisely what Brad & myself were advising when we wrote about the H-bridge config. Note that the output voltage is NOT 'higher', just that at the speaker terminals the voltage gets inverted, and hence 'appears' to be double.

I hope you know about limitations of a Class D amplifier . there are gang of reasons that why a class D amplifier isn't good choice with 5 volts supply !

please enlighten us ? Other than design of LC filter matched to the speaker - which is of course critical - what are the other issues? I would think that at such low voltages, with proper use of selected MOSFETS, the class-D would probably be the most cost efficient in terms of Audio-Watts/ Cost/ Power consumed.

In fact, here's a chip which does exactly this -- https://www.onsemi.com/pub_link/Collateral/NCP2824-D.PDF
 
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Note that the output voltage is NOT 'higher'
Hi again
May i ask you what you mean by that ? as i can remember i've noticed about a Push Pull amplifier with transformer which can easily increase the voltage with taking more current . i think you've misunderstood my meaning ?

please enlighten us ? Other than design of LC filter matched to the speaker - which is of course critical - what are the other issues? I would think that at such low voltages, with proper use of selected MOSFETS, the class-D would probably be the most cost efficient in terms of Audio-Watts/ Cost/ Power consumed.

And about this issue . i hope you know a class D amplifier needs more attention and experience while designing the PCB . because of the high frequency components of current . and as it appears author of this thread is a newbie in electronics . hence he/ she won't be able to design it's PCB .
You simply noticed about a class D amplifier . but it needs gang of experiences . in driving mosfets with proper method . creating enough dead time for mosfets . out put filter is pretty important . it's impedance should be normalized for the load impedance as well . creating a good SPWM signal requires enough experience . winding the inductor for a best class D amplifier requires more experience too . it's DC supply should have good features too . these are for an open loop class D amplifier ! a closed loop class D amplifier is so complicated for a newbie . and another thing is amplitude of your audio signal should be nearby amplitude of triangular wave . so a voltage amplifier is required . so what circuit should be sued for a voltage amplifier before comparator of SPWM ? some op amps ? transistors ? if so , would be just 5 volts sufficient for them ? i hope you know a comparator to deliver a good SPWM needs simultaneous supply ( +- VDC ) so that's not a good idea with these demonstrations to use a class D amplifier for this case .
Best Wishes
Goldsmith

- - - Updated - - -

By the way the IC that you've introduced is designed to prepare 2.4 watts across the 4 ohms load !
and how about it's input signal ? it should be at maximum amplitude to deliver 2.4 watts .
although 2.4 watts isn't required by the original poster . he / she needs 5/10 watts .
So that's not a good idea too .
 

I need a simple npn or pnp transisor based amplifier having load or output is 4ohm (1 or 3 or 5w) with +5v supply.........
 

At 5V single supply, a one-transistor amplifier won't give more than a couple tenths of a watt. That would be a class A type.

The next step up is a class AB.

Because I'm a nice guy...

and because I can't hope to make a million dollars from this design by marketing it myself...

I'll post the schematic.



Average power is around 1 watt.

The incoming waveform must have sufficient amplitude.
 

without transformer......
Hi again
That's impossible to achieve this power rating with 5 volt supply and a 4 ohm load without transformer !

Good Luck
Goldsmith
 

Hi again
That's impossible to achieve this power rating with 5 volt supply and a 4 ohm load without transformer !

Good Luck
Goldsmith

Yes goldsmith... we have already established that in this thread.
He is now asking for 1w/3w/5w... And we also pointed the way to achieve upto 2.5w max.
 

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