Inv Gain Clone with on board PSU

[peranders]

If you let the signal ground meat the power ground at the OG spot you will have a very good pcb layout.

.... but if you reduce the signal groundplane at the LM3886 then you can have more massive connections to pin 1 and 3. Let the groundplane and just beneath the R3.

 

[anbello]

I have changed the pads on the package for the LM3886 (to have more copper were needed), the package for the bridge to GBU (there are many good rectifier at 8A with this package) and now signal ground meet power ground at the OG spot.
What do you think of this last release?
Ciao
Andrea

 

[Bazukaz]

Hi,
Do you really need 220yF bypass capacitors ? Bypass caps are useful when leads from main caps to IC are long.
10 000 uF are close to IC.

regards,
Lukas.

 

[dfdye]

Do you really need 220yF bypass capacitors ?

I vote yes. You have room and can always take them off/not add them later. Keep the components on the board. It can't make the board bigger and will definitely add in flexability later. The additional caps will allow better power regulation.

David

 

[peranders]

Hi,
Do you really need 220yF bypass capacitors ? Bypass caps are useful when leads from main caps to IC are long.
10 000 uF are close to IC.

I think this is a good idea, besides it's common practice.

 

[anbello]

P-A, sorry, i would like to know if the layout in my Post #22 is good respect what you say in your Post #21:

.... but if you reduce the signal groundplane at the LM3886 then you can have more massive connections to pin 1 and 3. Let the groundplane and just beneath the R3.

I would also like to have some hints on good service (for quality an for price) in Europe to get some prototype board from the gerber or eagle files.

Thanks a lot

Ciao Andrea

 

[peranders]

P-A, sorry, i would like to know if the layout in my Post #22 is good respect what you say in your Post #21:

It looks pretty good now.

 

[dfdye]

I would also like to have some hints on good service (for quality an for price) in Europe to get some prototype board from the gerber or eagle files.

Thanks a lot

Ciao Andrea

I have used Olimex for prototyping and I have had pretty good results with the boards I got from them. I have not yet gotten back the double sided boards I have on order, but I will let you know how they turn out when I get them back. I think some others on the forum have also used them, and though the boards are not the greatest in the world, they are perfectly servicable and are pretty cheap. Also they take Eagle files directly and do all of the processing for the cost of the board, so they are easy to deal with.

Check out the details here:

http://www.olimex.com/pcb/

 

[frank1]

Eagle libraries

Where on earth did you get the Eagle library for the LM3886 ?
Eagle is driving me round the bend here.. getting nowhere fast trying to do my own board.
Frank

 

[dfdye]

I made my own. I am not sure if there is one available other than that.

 

[cb951303]

anbello I was looking for a compact layout like this, when it's finished would mind sharing its eagle files?

 

[frank1]

Eagle libraries

Any chance of sharing it then ?
The pin spacing has got me beaten.

Frank

 

[anbello]

Ok i like sharing, i hope if you get some improvement to the design you think the same way and so all of us will benefit from this.
Here his my latest revision, just a little less compact to accomodate for a larger package for C1, i would like to use a 4.7 uF polypropylene cap.
Any suggestion for this and for other components to form a detailed BOM?

 

[anbello]

... the eagle files

ciao
andrea

 

[peranders]

Well done! An excellent job... in theory. How good will it be in real life? The odds are good I think.

 

[anbello]

Well done! An excellent job... in theory. How good will it be in real life? The odds are good I think.

Sorry P-A i don't understand english very well, this comment is for the design or for the ideas on sharing?

ciao
andrea

 

[peranders]

What I mean is "I like it" and I'll wait for your hopefully positive results.

One thing is to do the design in the computer, an another to do it in real life. Prototyping is important but in your case you'll have good odds to succeed.

 

[cb951303]

thanks anbello
I'm looking for test results I'll test my self too in 2-3 weeks

 

[cb951303]

I only see the ground planes' borders as in the image below

An externally hosted image should be here but it was not working when we last tested it.

What's wrong with that, is it my Eagle (4.16)
thanks...

 

[dfdye]

Hit ratsnest and it will fill in planes.