I know...
Yes, sometimes I question the things I do. However, learning, experimenting, and making things are highly enjoyable to me.
An LCLC PSU has an output voltage of ~1.4 times the Vac of the unloaded transformer.
When the LCLC PSU is working within it's range of output current, the output voltage is ~0.9times the loaded Vac of the transformer.
The 12Vac transformer is likely to output between 10Vdc and 18Vdc depending on the current through the inductors.
Do not connect voltage sensitive circuits to this VERY VARIABLE output voltage.
When the LCLC PSU is working within it's range of output current, the output voltage is ~0.9times the loaded Vac of the transformer.
The 12Vac transformer is likely to output between 10Vdc and 18Vdc depending on the current through the inductors.
Do not connect voltage sensitive circuits to this VERY VARIABLE output voltage.
You will learn faster if you ask the right questions. For example, not "how do I vary the output from this (completely wrong for the purpose) power supply" but instead "is it possible for a newbie to improve on a standard computer power supply, and what do logic circuits need from their PSU anyway".
Yes
Haha, I apologize for my ignorance in this field. Perhaps I can PM you in the future before I pose anymore silly questions?
Haha, I apologize for my ignorance in this field. Perhaps I can PM you in the future before I pose anymore silly questions?
I don't provide free private consultancy, but I am happy to answer questions posed in the public forum.
A good question is preceded by some context, which tells us what you are hoping to achieve before telling us how you think you might achieve it. So in this case you should have first told us that you were planning to power a computer, then asked if a simple choke input PSU is suitable. We would have said no, and explained why. You will note that we were quite a way into this thread before we were even clear what you meant by 'LCLC PSU'.
You might be surprised to hear that it is quite common for newbies to post a circuit, then ask "will this work?". Our first question back then may be "work as what?" because it may not be obvious what the circuit is intended to do.
A good question is preceded by some context, which tells us what you are hoping to achieve before telling us how you think you might achieve it. So in this case you should have first told us that you were planning to power a computer, then asked if a simple choke input PSU is suitable. We would have said no, and explained why. You will note that we were quite a way into this thread before we were even clear what you meant by 'LCLC PSU'.
You might be surprised to hear that it is quite common for newbies to post a circuit, then ask "will this work?". Our first question back then may be "work as what?" because it may not be obvious what the circuit is intended to do.
What kind of load? If it is constant, then theoretically you can change output voltage by altering inductance, or by a phase splitter (hehe, this will kick tha *** of sound quality). But do you really have to alter the voltage? Load will decrease it by 10-40%, did you consider this?
The proper way is selecting the trafo with proper secondary voltage. How much do you think it mismatch?
Thank you
I really do appreciate you taking the time and answering my questions. I did not ask or mention what I was intending on using it for because that was not what I was trying to find out. I had also previously did my research on replacing the SMPS that a computer uses with a linear power supply. I acquired an ATX power control board which serves the function of an SMPS. I acquired this from Steve (SGX) who was extremely helpful and is currently using it in his music player. I have attached a picture of this board. All that was left to do was to supply the separate voltage.
http://www.diyaudio.com/forums/powe...egulated-voltage-circuits-73.html#post4491230
So, based on more research, it appears that the LCLC choke filter was used by numerous people with success on the DAC noted in the link below. I also have this DAC and intend on replacing the current psu with this one. It seems that they have had success of regulating the output voltage with a large bleeder resistor.
http://www.diyaudio.com/forums/digi...-192-24-dac-pcm1794-waveio-usb-input-215.html
I was really trying to find out if I could reduce the voltage with a trimpot and if this was the proper method. It seems I can achieve my goals with a bleeder resistor. Also, I contacted Belleson and inquired if I could use their super regulator in my application and they informed me it would work fine.
There are a lot of things in life I am grateful for and having a community such as Diyaudio is a minor thing that I am grateful for. Without this medium and the users, I would not be able to learn as much as I have and I definitely would not have been able to make my own electronics.
I really do appreciate you taking the time and answering my questions. I did not ask or mention what I was intending on using it for because that was not what I was trying to find out. I had also previously did my research on replacing the SMPS that a computer uses with a linear power supply. I acquired an ATX power control board which serves the function of an SMPS. I acquired this from Steve (SGX) who was extremely helpful and is currently using it in his music player. I have attached a picture of this board. All that was left to do was to supply the separate voltage.
http://www.diyaudio.com/forums/powe...egulated-voltage-circuits-73.html#post4491230
So, based on more research, it appears that the LCLC choke filter was used by numerous people with success on the DAC noted in the link below. I also have this DAC and intend on replacing the current psu with this one. It seems that they have had success of regulating the output voltage with a large bleeder resistor.
http://www.diyaudio.com/forums/digi...-192-24-dac-pcm1794-waveio-usb-input-215.html
I was really trying to find out if I could reduce the voltage with a trimpot and if this was the proper method. It seems I can achieve my goals with a bleeder resistor. Also, I contacted Belleson and inquired if I could use their super regulator in my application and they informed me it would work fine.
There are a lot of things in life I am grateful for and having a community such as Diyaudio is a minor thing that I am grateful for. Without this medium and the users, I would not be able to learn as much as I have and I definitely would not have been able to make my own electronics.
Attachments
No, I do not believe it is a constant load. Yes I have selected transformers with secondaries that are very close to the desired Vout. The drawback is the bridge rectifier increases the volts which I would then have to decrease. I was not aware that introducing a load would decrease the Vout that much. I just wanted to make sure it was safe and reliable before I connected it to any thing.
If not constant, then you have to determine minimal, maximal current, frequency limits of the fluctuation, and voltage tolerance of supplied device to determine if your lclc network is capable for the task. It doesnt provide stable voltage, it varies with load, so a simple adjustment can be insufficient.
Its not clear what you want to use it for, you mentioned too much things.
I am now totally confused! Adjusting the output of a conventional linear PSU by adding a shunt load is a good way to waste energy and encourage significant problems with magnetic induction. Is this supposed to be 'audiophile'?
There is a simple rule in electronics: to improve a circuit you need to understand it even better than the original designer. To replace a circuit with an alternative when seeking better performance requires similar knowledge and experience. SMPS designers know what they are doing. With respect, someone asking about adjusting PSU output voltage by adding loading doesn't know what he is doing, and therefore is most unlikely to end up with a better system.
There is a simple rule in electronics: to improve a circuit you need to understand it even better than the original designer. To replace a circuit with an alternative when seeking better performance requires similar knowledge and experience. SMPS designers know what they are doing. With respect, someone asking about adjusting PSU output voltage by adding loading doesn't know what he is doing, and therefore is most unlikely to end up with a better system.
I remember seeing a thread on here where somebody made an ATX compatible power supply using linear regulators. It was no trivial task too as the finer details make it far more complicated than you would initially think. The rails need to be closely regulated, have clean start up and shutdown, the various rails need to start in a specific order within a certain time frame, needs a standby/soft start circuit to trigger it, not to mention the current demands which can change rapidly.
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