tda 2050 datasheet says max +-25 v dc—this is regulated or unregulated dc voltage ???
—-i am using 16-0-16 v transformer after rectification,filter caps gives 22-0-22 v dc(non regulated)=44 v —which when load speaker connected surely drop voltage to 16-0-16 v on load=32 v (not measured best guess)
——–so what do you think i should get a transformer which when load applied should give 50 v ?
———thank you
—-i am using 16-0-16 v transformer after rectification,filter caps gives 22-0-22 v dc(non regulated)=44 v —which when load speaker connected surely drop voltage to 16-0-16 v on load=32 v (not measured best guess)
——–so what do you think i should get a transformer which when load applied should give 50 v ?
———thank you
As long as your supply does not exceed the maximum stated voltage, all will be well.
+_22v is recommended.
+_22v is recommended.
thanks——–
tda 2050 gives 15 v rms at 3.5 a for 4 ohm load—see the video—in 10:10 timing—
YouTube
—actually my point of view is whenever we apply unregulated transformer power to amplifier——-voltage will drop obviously—
example —-16-0-16 v after rectifier filter caps becomes 22-0-22 v dc unregulated—under load drops to 15-0-15 v dc=30 v dc————
so to meet +-25 v dc requirement i have to apply approx 21-0-21 v ac transformer
then why people recommend 16-0-16 v ac transformer for amp tda 2050 that has +-25 v dc max — in all forums i have seen ?
---i hope i am able to explain my doubt--------
tda 2050 gives 15 v rms at 3.5 a for 4 ohm load—see the video—in 10:10 timing—
YouTube
—actually my point of view is whenever we apply unregulated transformer power to amplifier——-voltage will drop obviously—
example —-16-0-16 v after rectifier filter caps becomes 22-0-22 v dc unregulated—under load drops to 15-0-15 v dc=30 v dc————
so to meet +-25 v dc requirement i have to apply approx 21-0-21 v ac transformer
then why people recommend 16-0-16 v ac transformer for amp tda 2050 that has +-25 v dc max — in all forums i have seen ?
---i hope i am able to explain my doubt--------
Do it that way:
The maximum voltage is +/-25v thus you never want to go above that.
A capacitor input supply while lightly loaded will give you about 1.414 * the ac input voltage. And you will drop around 1V in the bridge rectifier. Thus at first sight your ac input will be: 26/1.414 = 18.4.
But you cannot use a 18.4VAC input. First off because the voltage rating of the transformer is usually given with the transformer providing its rated current into a resistive load. Unloaded, it will give you quite a bit more voltage. Assume 5% if you cannot measure it before hand.
Secondly, you don't always get the same mains ac voltage. It can go up and down quite a bit. Here's again at least 10% to keep in reserve.
So, let's remove 15% of 18.4Vac. You end up at about 16Vac. 15Vac would be more conservative.
That was way too simplified; have a look here for more details :Linear Power Supply Design
The maximum voltage is +/-25v thus you never want to go above that.
A capacitor input supply while lightly loaded will give you about 1.414 * the ac input voltage. And you will drop around 1V in the bridge rectifier. Thus at first sight your ac input will be: 26/1.414 = 18.4.
But you cannot use a 18.4VAC input. First off because the voltage rating of the transformer is usually given with the transformer providing its rated current into a resistive load. Unloaded, it will give you quite a bit more voltage. Assume 5% if you cannot measure it before hand.
Secondly, you don't always get the same mains ac voltage. It can go up and down quite a bit. Here's again at least 10% to keep in reserve.
So, let's remove 15% of 18.4Vac. You end up at about 16Vac. 15Vac would be more conservative.
That was way too simplified; have a look here for more details :Linear Power Supply Design
You can never use the full potential of an amplifier chip with an unregulated power supply.
As very well explained above, you have to design an unregulated power supply such that the idle (almost unloaded) voltage is just below the maximum operational voltage of the amplifier chip. This is an absolute design constraint.
When the amplifier is heavily loaded from a high output level, and you need the full supply voltage, then the unregulated voltage drops through losses in the transformer, rectifier and also storage capacitor ripple and you have much less voltage than you hoped for.
Therefore, regulated power supplies are not just exaggeration if you want to get all out of the amplifier chip. The regulation eliminates the detrimental effects from voltage variation on the charge buffer electrolytic capacitors, in particular the 100 Hz (continental Europe) ripple from double-rectification sometimes heard as hum.
But, regulated power supplies are somewhat more complex (expensive) and need to be designed for fast response and with good current margins.
As very well explained above, you have to design an unregulated power supply such that the idle (almost unloaded) voltage is just below the maximum operational voltage of the amplifier chip. This is an absolute design constraint.
When the amplifier is heavily loaded from a high output level, and you need the full supply voltage, then the unregulated voltage drops through losses in the transformer, rectifier and also storage capacitor ripple and you have much less voltage than you hoped for.
Therefore, regulated power supplies are not just exaggeration if you want to get all out of the amplifier chip. The regulation eliminates the detrimental effects from voltage variation on the charge buffer electrolytic capacitors, in particular the 100 Hz (continental Europe) ripple from double-rectification sometimes heard as hum.
But, regulated power supplies are somewhat more complex (expensive) and need to be designed for fast response and with good current margins.
thanks----------i got the point----
unregulated---logic----limitation cannot use full power----for safe voltage operation
regulated----------i can use full power but do i need large 2200 uf caps before speaker if i use regulated 22-0- 22 v dc supply ?
unregulated---logic----limitation cannot use full power----for safe voltage operation
regulated----------i can use full power but do i need large 2200 uf caps before speaker if i use regulated 22-0- 22 v dc supply ?
If you use a symmetrical power supply you do not need to use a large coupling capacitor in series with the loudspeaker. The large coupling capacitor is only used when the output has got an important DC component, such as when you feed the amplifier with a single supply voltage and connect the loudspeaker between a single output terminal of the amplifier and ground. With a symmetrical power supply, just measure (before connecting the loudspeaker) at the output terminal of the TDA2050 that the DC offset (measured to ground) is no more than 50mV (and hopefully below 20mV). When you have verified that the offset is no more than 50mV you can connect the loudspeaker.
If you use a regulated symmetrical 22-0-22V supply you will be safe because you have a 3V margin up to the 25V which is the absolute limit for TDA2050. 22V regulated is a good choice.
Good luck!
If you use a regulated symmetrical 22-0-22V supply you will be safe because you have a 3V margin up to the 25V which is the absolute limit for TDA2050. 22V regulated is a good choice.
Good luck!
The output voltage of the mains transformer is:
Vout = mains voltage / rated primary voltage * rated secondary voltage * (1+ transformer regulation)
A 230:16Vac transformer with 8% regulation operating on a 254Vac supply will have a maximum output of:
Max Vout = 254/230*16*(1+0.08) = 19.08Vac
When rectified this becomes 19.08* sqrt(2) -(~0.5Vf to ~0.7Vf) = 26.5Vdc to 26.2Vdc
A dual 16Vac through a bridge rectifier could take the power input pins of the chip amp to near +-26.5Vdc
Vout = mains voltage / rated primary voltage * rated secondary voltage * (1+ transformer regulation)
A 230:16Vac transformer with 8% regulation operating on a 254Vac supply will have a maximum output of:
Max Vout = 254/230*16*(1+0.08) = 19.08Vac
When rectified this becomes 19.08* sqrt(2) -(~0.5Vf to ~0.7Vf) = 26.5Vdc to 26.2Vdc
A dual 16Vac through a bridge rectifier could take the power input pins of the chip amp to near +-26.5Vdc
thanks to everybody-----------
FauxFrench------if i use regulated dc power supply 22-0-22 v dc-----is there any problem of high frequency or other thing cuttof while songs, movies----actually this thing is confusing because all branded denon,onkyo uses unregulated supply--why ?
FauxFrench------if i use regulated dc power supply 22-0-22 v dc-----is there any problem of high frequency or other thing cuttof while songs, movies----actually this thing is confusing because all branded denon,onkyo uses unregulated supply--why ?
p { margin-bottom: 0.1in; line-height: 120%; } No, there is no problem the performance will only get a little better. I will explain:
A non regulated power-supply has got the advantage that it is significantly cheaper to produce than a regulated power supply because the regulation involves a number of extra components and a heatsink for the regulating transistor (normally linear series regulation). Even for good brands like Denon and Onkyo, production costs are important because it is commercial series production. Another advantage of the unregulated power supply is that you have little power losses in the supply because you have no regulation series-transistor.
Think of an unregulated power supply as a raw source of electrical energy with some voltage ripple and where the voltage will vary with temperature and loading.
If you then take this raw, unregulated power source and put a regulator on the output you can have an almost perfect, "stiff" (almost no ripple and very little variation) voltage at the output. This is because the regulating transistor filters the voltage variations at the input of the regulator such that you have only the stable part of the voltage at the output.
Thus, the advantage of a good regulated power supply is that the output voltage is almost perfect ("stiff") for an amplifier and no noise gets into the amplifier from the supply. You can use almost the maximum supply voltage of the amplifier circuit because there is almost no voltage variation at the output of a regulated power supply. The disadvantage of a regulated power supply is higher costs and some heating in the regulating transistor that needs some kind of heatsink.
When the engineers at Denon and Onkyo have designed a new power amplifier circuit they connect it to a high quality laboratory power supply, which is a regulated power supply with variable output voltage. With the almost perfect voltage from the laboratory power supply the engineers can measure the full potential of the amplifier because the laboratory power supply sets no performance limits. When the engineers are happy with their power amplifier design, they go to the production engineers who tell them that using a regulated power supply, like the laboratory power supply, is far, far too expensive. So, the production engineers start cutting down on the costs (but also performance) of the whole amplifier-product design such that most of the qualities of the original amplifier remains. When the production engineers have finished their work, the amplifier-product is put in series production and the specs you see are those for the cost-reduced product.
Hence, regulated power supplies are for the most expensive audio amplifier products only, because they add costs but also improve the performance a little.
Regulated power supplies are found for different purposes. Some are rather slow and only suited for rather stable loads. A characteristic of an audio amplifier is that it is a very dynamic load (current varies rapidly with the sound-level and frequency of the music). Therefore, the regulated power supply used for an audio amplifier must have a regulation loop that is fast (to compensate for the fast load variations) and have a good surge current margin such that transients in the music are not distorted. I normally prefer to design my own linear power supplies and avoid SMPS because they often have a less fast response (and make much more noise).
A non regulated power-supply has got the advantage that it is significantly cheaper to produce than a regulated power supply because the regulation involves a number of extra components and a heatsink for the regulating transistor (normally linear series regulation). Even for good brands like Denon and Onkyo, production costs are important because it is commercial series production. Another advantage of the unregulated power supply is that you have little power losses in the supply because you have no regulation series-transistor.
Think of an unregulated power supply as a raw source of electrical energy with some voltage ripple and where the voltage will vary with temperature and loading.
If you then take this raw, unregulated power source and put a regulator on the output you can have an almost perfect, "stiff" (almost no ripple and very little variation) voltage at the output. This is because the regulating transistor filters the voltage variations at the input of the regulator such that you have only the stable part of the voltage at the output.
Thus, the advantage of a good regulated power supply is that the output voltage is almost perfect ("stiff") for an amplifier and no noise gets into the amplifier from the supply. You can use almost the maximum supply voltage of the amplifier circuit because there is almost no voltage variation at the output of a regulated power supply. The disadvantage of a regulated power supply is higher costs and some heating in the regulating transistor that needs some kind of heatsink.
When the engineers at Denon and Onkyo have designed a new power amplifier circuit they connect it to a high quality laboratory power supply, which is a regulated power supply with variable output voltage. With the almost perfect voltage from the laboratory power supply the engineers can measure the full potential of the amplifier because the laboratory power supply sets no performance limits. When the engineers are happy with their power amplifier design, they go to the production engineers who tell them that using a regulated power supply, like the laboratory power supply, is far, far too expensive. So, the production engineers start cutting down on the costs (but also performance) of the whole amplifier-product design such that most of the qualities of the original amplifier remains. When the production engineers have finished their work, the amplifier-product is put in series production and the specs you see are those for the cost-reduced product.
Hence, regulated power supplies are for the most expensive audio amplifier products only, because they add costs but also improve the performance a little.
Regulated power supplies are found for different purposes. Some are rather slow and only suited for rather stable loads. A characteristic of an audio amplifier is that it is a very dynamic load (current varies rapidly with the sound-level and frequency of the music). Therefore, the regulated power supply used for an audio amplifier must have a regulation loop that is fast (to compensate for the fast load variations) and have a good surge current margin such that transients in the music are not distorted. I normally prefer to design my own linear power supplies and avoid SMPS because they often have a less fast response (and make much more noise).
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