Prototype board

So, the prototype board finally arrived for the power supply. Unfortunately the spacers that I had intended to use wouldn't fit in the tiny holes already provided, and the holes in the board were so close to the edge that I couldn't just drill them out, so I have drilled out some little holes a bit further in, not ideal, but still was just about right. I'm only loosing a small amount of space, and in the project space isn't at a premium, so it doesn't matter. I have found the pillar drill at work so no more excuses for shoddy hole drilling! Although they seem not to have any kind of vice or clamp over there, so i will have to source something like that if I want to drill a huge hole in the wooden front panel for the pots. Here is a picture of the idea anyway, probably small components and op -amps and stuff on the bottom, and big power hungry components on the top, so that I can get maximum air flow around them, for cooling.

Bench Power supply circuit is nearly ready!

Hi,

   So we are getting very close. The first circuit creates our un-regulated supply, a 38V supply for the op-amps for the circuitry and a 12V supply for the internal cooling fan.

Then we have an op amp based power supply design with current limiter based on the LT3080 voltage regulator. In this circuit we are using 2 in series to double the amount of current we can deliver. These regulators rely on a minimum load of 1mA generated by I1. I2 is simply for testing (to represent the load on the output of the supply). This supply should give between 32V and 0V, and 0A to 4A. I believe that the transformer I have will only provide 0.5A at 48V, but I have designed the circuit to support more current if I choose to change the transformer in the future.

This has taken me over a month, and is only what I guess is a 'first draft'. I need to get some people who really know how these things work to give it a once over before I start designing the PCB!

Bench PSU Housing

Hey, So I didn't give up, but I built a few board up and decided I needed a bench power supply. I have been designing a bench supply for a while now. I have started putting the case together. I have cut up the front of an old draw and am going to make it into a box to house the design. Last night I marked up the wood with the components I want on it.

 Then I have drilled and sanded for my life until the holes are the right side for the components. Here is the back, and below is the inside of the back. I have made a little bit of a hash of the front so it needs more work. I have the circuit for the supply nearly complete, but i'm still grappling with a few calculations (although im sure it'll all change when I get the design out of the simulator anyway!) - I have purchased a transformer which very shortly I will put a dynamic load that I have at work over it and figure out exactly how many bolts and amps I am going to get out of it. I intent to try and make a printed circuit board, etch it myself (because I can't sure veroboard for this project, as I'd smoke the copper track due to the high current). I'd like to finalise the circuit in the simulator before I get to the task of laying out a single sided PCB (as I beleive double sided will be too tricky). Watch this space for final schematics. Hopefully I will finish it soon so I can get on with the task in hand, which is building the synth! (Project update: I have the first two boards completely built up, thats Midi to CV, and Waveform generator. I just want a current limiter to test them with to ensure I don't smoke any of my lovely components!)