Could someone double check my board?

[bradells]

Hi all,

First time poster, long time searcher here,

First real board (of my design, done a few single sided of others designs with little problems), and just would like some input on the artwork on it. Power is red (component side), and signals are green.

I have a few questions, On my power layer, I have a filled ground plane and in the bottom left there is an area between my two power traces that run up the board isn't connected to the ground signal. Aside from it not being connected to the ground, is it a bad thing to have it there? (It has no connections to components that may think its ground)

Also, if I put another filled ground plane on the signal (Green) side, and put in a vias to connect the unconnected ground plane will it be that beneficial? And then worrying about unconnected areas on that layer (Ground on the signal layer)?

BRad

 

[bradells]

And here is the signal layer ....

 

[BradAvenson]

This is a bit easier to help you with if you also post a schematic with the same part numbers. 

I would watch to keep the loop small around the gain control for the THAT preamp. 

 

[bradells]

How about this, I moved the IC's up to closer to the Gain control, and routed the RG1 and RG2 traces so they are side by side. And moved the power connector so its a straight line to the IC's

 

[bradells]

And heres the sch. Basically taking their datasheet and combining it with the DN138

J1 is Signal (Ground, +, -, Chasis)
J2 is Output (Ground, Sig)
J3 is Power (Ground, +, -)

Thanks Brad,


BRad

 

[Twenty Log]

One minor (and this is minor... very minor) manufacturing etch "violation".... There are 2 acid traps that I see where the angle of the copper trace for D3 and D4 (on the left hand side pins) is an acute angle...

I would not modify it for your purposes unless you have time, but it does potentially "Trap" the acid better and can over etch it a little bit... not critical I imagine but FYI...  I would come in at a right angle and attach the pin for D3 and D4 perpendicular...

The trace above the top of pin1 for C4 (+ of Electrolytic) can have some more room for my taste... But that's just me being paranoid if no solder mask (or in my usual cases here "slobber mask") ....

 

[Harpo]

Pin spacing and outer dimensions of C5 might need revisiting. Is this 6800uF cap needed at all, or is your servo circuit only optional ? If optional, a provision to connect THAT151x-pin5 to gnd might look better than jumping an unfitted servo-pin3 to pin6.
There is unused space for an optional (rev-log) pot or gain setting switch/resistor arrangement, probably replacing your VR1 trimmer. I doubt, you'll get lucky with a 10K linear taper trimmer, giving 3.5dB increase in gain within the 1st 50% of trimmer rotation, but YMMV.
Mounting holes might not be the worst idea.
just my 2ct

 

[bradells]

Guess I should have mentioned that I haven't gotten all the parts in yet (being the rev log pot and cap you mentioned in the gain control loop) to update my libraries ... basically looking if there is any major things wrong with layout (other than not quite the right parts in the very limited library) like routing issues and layout which have already been mentioned.

But definitely a good thing to bring up in case I did forget that they are the wrong footprints before I made a board (or worse, ordered!) or someone takes this artwork ...