Yes, I know I haven't been very precise, and I never was really intending to be very formal here with the way I present my questions. The reason I've been doing this is because I really was just curious if, as the name suggests, it was possible to drive the primary of a transformer to make a crude power supply, not so much discuss the details of the end product.
But yes you're right I should be more precise with my wording, especially in a more technical setting such as this forum.
I originally planned on using the transformer to make a 1.25-25v lm317 based power supply where current and voltage control would be done with an atmega328p microcontroller, quite similar to the design Dave made for his micro supply. I later changed my mind and wanted to use a switching regulator so that I could make it more efficient and increase the current capability at the lower voltage outputs. I never thought 5A at 25V was possible, but maybe down at 3.3-5V. Ideas that I thought of to design a switching based power supply were a tracking buck regulator with a linear output stage. This got me wondering if I needed the transformer at all, or if I could make use of some 300-400W PSUs I have. Using a tracking boost converter and a linear output stage came to mind, with either the 12V or 5V output of the PSU. Other ideas included a fixed boost regulator to around 35V and a buck regulator to change it from there, or a boost-buck switching regulator to try to reduce complexity.
The main control IC I've decided on is a dsPIC33EP16GS506 because of its 12 bit ADC and 2 integrated 12 bit DAC outputs. Beyond this, I haven't decided on any switching or linear regulators.
I'm aiming for 30v out max, although a greater output voltage would be more preferable, and a 3-5A output current.
Do any of the afformentioned topologies posses the capability of creating the desired output without any major issues? Or should I abandon the higher output current and stick with an lm317?
And thank you if you are still willing to answer my questions.
Stick the tranny on a set of scales and weigh it.
That should give us a good starting point as to guessing it's VA rating.
I've heard this as a method before, but was never clear on the numbers. I'll certainly weigh it in the morning, thanks.