I cannot find a full wave voltage tripler circuit on the internet using a non-center tapped transformer. I am using a 9 volt AC transformer. Can someone help me because I don't know how to design it. I want to power some pre-amplifiers. I need to use the doubler stage and the tripler stage. The doubler stage would power the preamplifiers and the tripler stage would be for phantom power for a condenser microphone. Please make it as simple as possible. I want to use a common ground. Thank you.

I'm sorry the first stage will power the pre-amplifiers which would be about 12 volts--not the doubler stage--that would be skipped. Also I might want to put a 12 volt 7812 at the doubler stage to power the preamplifiers.

 

If you full wave rectify a 9V AC output and smooth with a capacitor you will get around 10.7V DC which may be enough for the pre-amps although for audio I'd look to get a ripple free supply and would recommend ditching the transformer and using a switch mode power supply with a 12V DC output - pretty inexpensive these days. I think the range of voltages for condenser microphones varies from around 11 to 52 volts whilst studio microphones typically work with 48V. For audio it needs to be pretty clean! Take a look at https://www.electronicdesign.com/te...uses-tiny-dcdc-converter-plus-capacitor-trick

 

not aware of a full wave voltage tripler.

 

not aware of a full wave voltage tripler.

You mean it's not possible to design a full wave voltage tripler circuit using a non-centered tapped transformer?

 

You mean it's not possible to design a full wave voltage tripler circuit using a non-centered tapped transformer?

A transformer with 3:1 turns ratio?

 

What I mean is that by it's nature a voltage tripler is a half wave device. I have never seen any circuit claiming to bea ful-wave voltage tripler.
BUT I do have experience with a full wave voltage doubler and that circuit produced well over 300 volts when driven from the 10 volts mains power.
One thing that you may not be aware of is that in many instances the 48 volt phantom power is not required to be 48 volts, because many microphones only use 12 volts.
So I suggest using a full wave voltage doubler and check to see how well the microphones perform on that voltage, which will probably be over 20 volts, since the microphones are a very light load..
Is the 9 volt transformer part of a wall plug in package?

 

What I mean is that by it's nature a voltage tripler is a half wave device. I have never seen any circuit claiming to bea ful-wave voltage tripler.
BUT I do have experience with a full wave voltage doubler and that circuit produced well over 300 volts when driven from the 10 volts mains power.
One thing that you may not be aware of is that in many instances the 48 volt phantom power is not required to be 48 volts, because many microphones only use 12 volts.
So I suggest using a full wave voltage doubler and check to see how well the microphones perform on that voltage, which will probably be over 20 volts, since the microphones are a very light load..
Is the 9 volt transformer part of a wall plug in package?

Yes the 9 volt AC transformer is a wall adapter that produces 11 volts ac under no load. It is rated at 250 milliamp 120v.

 

An AC sine wave has a full wave value and an RMS value. It's the RMS value for AC that is most often considered. The reason for that is due to the nature of a changing wave form. As it approaches its full peak waveform the current drops off significantly and is pretty much useless. Take any AC value and multiply it by 1.414 to understand its full wave potential. A 9V transformer (and I'll assume 9VAC is an absolute value) 9 x 1.414 = will peak out at 12.726 volts. If you were to rectify that AC voltage and use filter caps to smooth out the wave (in this case it's not really a wave. On a scope it's a flat line (there may be some ripple observed)) the smoothed voltage "MINUS" the forward voltage drop of the bridge rectifier, let's assume 600mV per rectifier - given that only two rectifiers will be conducting at any given moment - 2 rectifier voltage drops would be 1.2V. Your final voltage (in a perfect world - no line losses or other losses) would be 11.526 VDC rectified and filtered.

As you load the output it will drop depending on the load you put on it. Lighting an LED lamp wouldn't drop it very much at all. And I'd be purely guessing at what that might be. But if you run a DC motor on it - again depending on the particulars, motor size, power supply capability, etc. - the voltage will drop more significantly. It stands to reason that if you were to dead short the output then the output voltage would be nearly zero volts. Due to imperfections in components and wires there WILL be some voltage somewhere. There has to be. The power supply will be pushing out at its full capacity, meaning as many amps as it is able to. The problem with that is it will overheat the bridge rectifier and exceed the BR's current capabilities and it will blow out. OR a fuse will blow out if you use the correct value to protect the rest of the circuit. But for the sakes of SnG (sh*ts & giggles) assume the wires won't burn, the BR won't fail and there's no fuse in the circuit - your transformer will overheat to the point of failure Or possible FIRE.

As Jerry-Hat-Trick recommends, (post #2) find a dirt cheap PWM Supply. They're darned plentiful and some places give them away.

I'd look to get a ripple free supply and would recommend ditching the transformer and using a switch mode power supply with a 12V DC output - pretty inexpensive these days.

 

I hope you can see how you might make use of a common ground, at least on the output.

 

View attachment 301995

I hope you can see how you might make use of a common ground, at least on the output.

In the circuit I attached I can use the output at C1 and c3 with a common ground. I can use transistor and capacitor filters at the output of both.

 

Yes the 9 volt AC transformer is a wall adapter that produces 11 volts ac under no load. It is rated at 250 milliamp 120v.

You mean 120 volts main output not 10 volts right?