PCB layout, can someone check, in particular the 0V bit?

[case-sensitive]

Hello,

this is meant to be a crossover for an amplifier project. I heard ground is meant to refer/lead to a single point. Tried hard but its just too much going on on the board. Is my layout ok so far (see pictures)

board, ground put on top layer so its easier to see
**broken link removed**

schematic, ground shown dotted
**broken link removed**

Cheers,

Case

 

[mvs sarma]

Instead of a GIF or JPG, you may post the eaglefiles themselves so that verification becomes easy.

 

[case-sensitive]

there they are

 

[mbarazeen]

it seems still you can relocate some components to reduce track lengths and make smaller PCB. also would be easy for you to check with your schematic..

 

[case-sensitive]

the schematic I made up, its a low pass, a bandpass and a high pass. Works essentially in a different layout, just creates too much noise, maybe because I put ground into a loop instead a star. The dummys I left in there in case I have to change the frequencies, in paticular for caps its hard to find particuar values, so can make it up for some in series or parallel.
This board is an replacement for the old board so it has to have same size and same holes, because its in my amps already.
And it should be single layer, GND I put on top just for demonstration.

 

[ronsimpson]

I like to either do 'star' or ground plain.
If star; i would take the grounds form J1,2,3 (output) back to each IC (TT, MT1, HT). That way each IC would have its own ground.
If ground plain; then make a 'polyfill gnd' and let you cad program fill all unused areas with ground.

Use a smart ground or a large solid ground.

 

[ronsimpson]

Ground plain

 

[case-sensitive]

I like to either do 'star' or ground plain.
If star; i would take the grounds form J1,2,3 (output) back to each IC (TT, MT1, HT). That way each IC would have its own ground.

trying, looks trouble. Suppose ground plane is easier and shorten signal ways.

 

[Boncuk]

Ground plain

Hi Ron,

your PCB looks good. However I suggest to make a restriction area around the mounting holes.

Using a metal enclosure you could get an unwanted connection between the ground pour and the case using metal stand-offs.

Something like that: Use layer 42 (b-Restrict) and trace width zero. Draw a circle around the mounting hole and let it be 0.635mm larger than the dimension line. That way the screw head (stand-off) is far away from the mounting hole.

For the top layer use layer 41(t-Restrict)

Regards

Boncuk

 

[Blueteeth]

Whether to use ground plane or point-to-point ... that seems to be a source of tension in the audio world. I tend to use ground plane in pretty much all my circuits, of any frequency, and I've never had noise/ground loop problems. But then it comes down to part placement (and power input placement).

 

[case-sensitive]

Will clean it up later,could shorten some paths. Did cut out the corners exactly for that reason, metal casing. Plus you have to remove less copper when using ground plane.

**broken link removed**

and power input placement

suppose it better is stars as well? Same ohms law. Then again, its more important each chip gets symmetric voltage because it has no GND?

 

[case-sensitive]

fixed it up.

 

[mvs sarma]

While improvement is continuous, please my artwork with little changes
we can perhaps remove the bridge resistors of 0 ohms and while in artwork we can change layer for a specific section of track and have a jumper there later. see one i had managed at bottom

 

[case-sensitive]

that makes life easier, don't have to put bridges into the schematic. But getting the board made elsewhere, cheaper than buying the raw material down here. So they may think its a double layer board which costs extra. And its only 2, so no point making it double layer, biggest expanse in their quote is the setup.

 

[mvs sarma]

sure.
you only provide the solder layer to them and specifically tell them to make single layer. there could be ways for it even under eagle.
i fear for 2 PCBs , home brewing would be still cheaper, as industry has to use films etc and all such overheads would be dumped on us, unless you catch hold of a local cottage industry person who could help you.

 

[case-sensitive]

**broken link removed**
AUD 25 each. futurlec PCB fab quoute for 2 off 125x 150 boards AUD 41.25, 4 bucks shipping. Comes with holes, maybe. I should give them a try...

 

[case-sensitive]

4 boards including them drilling holes and tinning it, for $20. Different project, but I wanted to try them small scale first. Everything fits and holes are right size.