V3 Universal Power Supply Circuit Board

What you see is what you get. There are two rectifier boards and two filter cap boards - one for each rail. Note the scoring lines where you can break apart the supplies for each rail and/or the rectifier boards to fit your case layout.

If you want to go dual mono for your F5 you will need two sets ($58).
 
thanks a lot! So 8 cap space by default. I am going stereo v2 so with my 10000uF caps it is recommended to go 2x8. Now some pics were showing these installed in the big amp case showing 2x8 caps so I got confused. I guess I need capacitor boards from 2x kits just not sure if I have to get these with extra 2x rectifier boards...
 
If you order 2 board sets you will have 4 rectifier boards and 4 capacitor boards. You don't have to use a bridge rectifier per rail, but there are a lot of folks who think it's a good idea.

You can always offer up unused rectifier boards in the swap meet or use them on another project.
 
Notice on the schematic the diodes are duals. MUR2020CTPBF-ND would be more appropriate. 200V is plenty, but if you want your diodes to keep up with the expected current. I'd go at least 16A, the cost difference is minimal and the reliability is higher. This is the part recommended in the BOM MBR20200CTGOS-ND

What is the advantage of dual diodes as opposed to single such as Fairchild FFPF30UP20S? Can only dual be used with the board?
 
Indeed. I was focusing merely on the "dual" aspect. Is this merely to provide more current capability? (Apologies if I am asking in the wrong part of the forum but I am hoping to be able to understand what drove the design of this part of the board. I have to date only used TO-220 diodes.)
 
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It seems to me you probably need to take the integral over a complete cycle: Integral( abs(vd(t)*id(t)) )dt) and then multiply by (1/period) to get the average power the diode dissipates, per cycle.

Yes the absolute value function is needless and picayune mathematical rigor, since the power dissipated in forward bias is many orders of magnitude greater than the power dissipated in reverse bias. On the other hand if you implement it this way in a spreadsheet, your formulas are WAY less complicated.
 
I realise now that the answer is much more complicated! Looking at the datasheet for the FFPF30UP20S as an example, however, wouldn't seem to provide enough information. Perhaps, a Spice model is the easiest way to run the analysis.

In any event, I take on board the point that if Vf depends on current then having dual diodes, all else being equal, will be of benefit but otherwise one can choose a diode with low Vf. Such diode may have other good characteristics such as ultrafast recovery to boot.

Thanks all.
 
Pass F5T PSU Fairchild Diode pinout question

^^ The pin out is the issue with the Fairchild part.


Can someone more knowledgeable than myself (lots out there I'm sure, I would bet the family farm on it...) elaborate on the "pin out issue" of the Fairchild diodes mentioned above.

I was planing on firing up the Hakko today and soldering in the diode board components and read Bob's reply and then got confused :confused:by his comment, since I am going to use Fairchilds (although, I will be using the FEP30DP-E3/45's, 200V 30A TO3P and realize the pin difference). I also have some Vishay MUR3020WTPBF diodes on hand that I can use. Any preferences on either for a V2 build? I was planning on using the Fairchilds, but can use the Vishays, if they have an advantage...

Also, I noticed that the Version 3 diyAudio diode boards have the white dot marked on the diodes' right pin pad and the diode has the dot marked on the center pin. Could someone explain?

Many thanks in advance. Your help will be greatly appreciated...
 
Look at the data sheets for the pin outs - a single usually uses the outside two leads while a dual has a common (typically cathode) in the center and the two anodes connect to the outer terminal.

If you want to use flying leads to the diodes, then you can use anything as long as you connect to the board in the right places.