lm3875 single sided pcb layout

[SolderN]

Hi everyone I am new to the forum!
I build guitars, pedals and I want to get into amps. Chip amps sound like the best way into the amp world. I picked up some Lm 3875t chips and now I am looking for a pcb pattern for it. I have used the search function but was unable to dig up a good layout.

 

[raudio1969]

How about this?

http://www.audiosector.com/images/lm3875_se_pcb.gif

 

[454Casull]

That doesn't look single-sided to me.

 

[AndrewT]

Hi,
indeed it is not single sided.
You could implement the blue traces with hard wiring to the components leads left slightly long.

 

[SolderN]

Yeah, I think I will go that route. I know I could have had this amp built already on perf but I wanted an amp I could take out of the house and not worry about. If it was a home amp I would buy some nice perf and go to town but this thing is going to be moved around more.
I am almost done with the board. I would post it but out of respect for the designer I will not.

 

[peranders]

Why can't you publish your own work? The engineering level of a basic LM3875 design isn't particularly high you know.

 

[SolderN]

The board I have is an adaptation of his layout. I know these things are as basic as it gets but I don't want to put anyone in a position where they choose my version of his board because it's free. He took the time to get them made up , his prices are fair and I don't want to detract from his sales. That is how I see it. He may have even published the large snapshot on his site for guys who were handy with photo shop. I don't know. I can use eagle I have not created any devices for my library yet and at the moment I don't have time to learn.
I know very little about what is needed for a good layout so that is something I need to study.
I would like to ad that it might not be a bad idea to get some brass rivets for the holes if you make the boards. You can get them on ebay cheap.

 

[peranders]

....
I know very little about what is needed for a good layout so that is something I need to study.

It's hard to give you any hints of improvement if we can't see anything

 

[SolderN]

Ok, I guess I need to clarify. I took the Audio Sector board modified it in Gimp ( it like photo shop) and now I have a board I can use. Because it started out as as Audio Sector design I will not post it. If I had started from scratch I would post it. I was surprised I did not find a ton of patterns when I started looking, it seems like a common chip.

 

[peranders]

Notice that this is a double-sided design.

 

[Idefixes]

May be it will help

 

[Idefixes]

The layout

 

[Idefixes]

The schematic

 

[Idefixes]

Implantation

 

[Idefixes]

This all function well since several years

 

[Idefixes]

next

 

[SolderN]

You know you could have posted that a little sooner ! I spent over an hour yesterday cleaning the other board up. I like your better. Thanks!
What is next is that an LM3875 amp with tube pre or is that another chip?

 

[SolderN]

Do you care if I post that on another site? I will give you credit for it.

 

[Idefixes]

The amp part is the same, i just put a buffer tube in the same box.
I build this amp in 2004. As i was a complusive builder this unit go to a friend, an run dayly since. Picture was on decibeldungon pages. You can post it on another site.

Marc