Help with EAGLE CMoy design, please =)

[mr-awesome]

any luck on the new schemtaic, if you post what you have, like what you did before, i can work on it in my drafting class, ive got a month left of school, and im already done in the class. the teacher would also help me in the placement etc. i dont know much about the types of caps, so i dont know what to pick out in eagle, but if you provide a schematic i can load it up and play with the board layout.

also:
1>did you add r5, im an IEM user and ive heard it helps with some noise.
2> in autocad there is a distance/measurement button that tells you how big the project your working on is. on eagle is there a similar tool, so i can figure out the size of the board I.E. 2in x 1.8in.

 

[Joshatdot]

Quote:

Originally Posted by AndrewFischer /img/forum/go_quote.gif 9+9 = 18v. 16V cap is not a good idea. A little. It also depends on which line you use. My recommendations are Nichicon UPW, Panasonic FM, or Elna RFS. RFS is the best sounding but they are less likely to fit in your Altoids tin. If you can't get a 470µF in one of these to fit, try 220µF. When you had the caps in series you only had 470/2. In any case with electrolytics quality matters at least as much as quantity.

So for tiny 470uF 16v caps, I would need two of them, one for +9V and the other for -9V. Other wise I need a single 470uF or 220uF 25v cap.

Best sounding? power cap?

 

[Joshatdot]

Quote:

Originally Posted by mr-awesome /img/forum/go_quote.gif any luck on the new schemtaic, if you post what you have, like what you did before, i can work on it in my drafting class, ive got a month left of school, and im already done in the class. the teacher would also help me in the placement etc. i dont know much about the types of caps, so i dont know what to pick out in eagle, but if you provide a schematic i can load it up and play with the board layout. also: 1>did you add r5, im an IEM user and ive heard it helps with some noise. 2> in autocad there is a distance/measurement button that tells you how big the project your working on is. on eagle is there a similar tool, so i can figure out the size of the board I.E. 2in x 1.8in.

I was away for the weekend and I am working on it again. I am playing around with a single 25v power cap or dual 16v caps, but I think I'll go with a single.

1. I have not added optional R5 yet (but there is room for them). I was designing this CMoy for 60+ ohm cans.
2. There is a size graph when designing the layout. I could print a layout on paper and see how the pieces line up with the hole dots on the paper.

 

[AndrewFischer]

Quote:

Originally Posted by Joshatdot /img/forum/go_quote.gif So for tiny 470uF 16v caps, I would need two of them, one for +9V and the other for -9V. Other wise I need a single 470uF or 220uF 25v cap. Best sounding? power cap?

Yes. With two 470µF caps they are in series. Each cap sees 1/2 the 18V supply. Total capacitance is 235µF.
A 220µF 25V cap is equivalent. I vote for a single cap as it simplifies the design.


My opinion is the Elna RFS is the best sounding of the non-boutique electrolytic caps. They are not bad and cost well under a dollar. Downside is they are big. I doubt the 220µF is going to fit. The 100µF Elna RFS might. Digikey part number 604-1055-ND. It is 10x16mm. May have to put it on its side.

http://www.elna.co.jp/en/ct/pdf/RFSe.pdf

After that there is the Panasonic FM and the Nichichon UPW. Digikey carries both of them. The FM is usually cheaper and has somewhat better performance. UPW isn't bad though. I use them. The UPW has a wider value range, but you won't be needing a 400V cap here.

I'll let you look at the data sheets and see what fits.

 

[Joshatdot]

I am going with (at lest sizing for) Nichicon UPW1E221MPD, Digi-Key 493-1823-ND, CAP 220UF 25V ELECT PW RADIAL.

 

[Joshatdot]

The board is 1.10" x 2.00". Can someone check my Schematic, specifically the TLE railsplitter. I am not 100% sure I wired the pins correctly.

Schematic


Layout


Traces

 

[AndrewFischer]

Check your links.

 

[Joshatdot]

Quote:

Originally Posted by AndrewFischer /img/forum/go_quote.gif Check your links.

I checked my power supply schematic & Tangents. His TLE is wired differently than mine.

Mine has IN connected to V+, COM connects to GND, OUT connects to V-

Tangent's has IN ~ V+, COM ~ V-, COM ~ GND.

 

[AndrewFischer]

I meant your img links. They weren't showing up earlier.

I'll try and find time to check your work later today.

 

[Joshatdot]

I replaced direct links to clickable thumbnails...links should work

 

[mr-awesome]

they work fine for me.

 

[Joshatdot]

Over the past two weeks designing these boards I came to a conclusion...It would be nice if op-amps had the +IN pins & V+/V- on one side and the OUT & -IN pins on the other side

 

[mr-awesome]

well that would just make things easy now wouldnt it. what company out there wants things to be easy for customers.

are you still doing auto route, i see the traces are small, if you upload the schematic and board files, i can work on the traces during school, as a bigger width.

also when doing the lines, is it better to have 90 degree angles, or the 45 degree bends

 

[gjavitt90]

when i put the tle in my cmoy i did it like tangent: in=v+ out=ground comm=v- worked for me. your way sound like it'll totally mess up the rail splitter. but maybe you have your circuit wired differently...

 

[colonelkernel8]

You should probably not do a two layer board, unless you are going to get one made by like Olimex. But thats pricey for a board for a cmoy.