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1  Using Arduino / Microcontrollers / Re: Custom board review please on: April 03, 2014, 07:10:52 am
How'd you layout the board without a schematic to start?

Yeah that seems kinda crazy - looks like it was laid out with Eagle...

OP - Generally looks pretty tidy but I'd pick up on 2 things:

1) Appears to be through-hole components on both sides of the board - that's what I'm assuming for those inside the bounds of the Mega chip. There's plenty of space on the board so could these not be moved out and up to the top side? Liable to suffer less damage there.

2) End-mounted resistors - nothing technically wrong with this, but it looks unprofessional to me, and again there's plenty of space to lay them out flat.
2  Development / Other Hardware Development / Re: First surface mount board. Help me check my board. on: March 13, 2014, 08:04:43 am
Here you go - Tracks in orange are simplified routing

Also the connections between orange 1-1 and 2-2 could be done on the top layer to remove necessity for vias and also help with simplifying bottom layer more.

(Caveat - I can't 100% guarantee this is ok because some of the traces are obscured in the screenshots)
3  Development / Other Hardware Development / Re: First surface mount board. Help me check my board. on: March 12, 2014, 10:13:49 am
On the blue side there's a couple of traces at the bottom that go below the big connector right to the edge of the board that could easily be rerouted more directly and wholly inside the connector footprint. Same goes for the connector on the right hand edge to a lesser extent.

Generally looks pretty tidy though!
4  Using Arduino / General Electronics / Re: Advise for circuit, and pcb layout on: March 04, 2014, 08:04:44 am
My input for what it's worth..

I'd turn off the component values on the PCB layer before sending it off - or spend some time tidying everything up so there's no overlapping text! Have a look at the 'smash' command - this lets you position the text independently of the component placement.

Just because the fab house has a minimum clearance, it doesn't mean you should always use it - there's lots of instances where it looks like min clearance is used when a much safer clearance would be perfectly possible (especially traces passing vias)

There's a school that says right angles in traces are bad, I certainly avoid them but that's mostly for asthetics - but there also seems to be a lot of unnecessary corners in many of the traces. As was mentioned earlier, turn off all layers except one copper layer at a time and look for any deviations in a straight route that are not absolutely required.

if you shifted JP1 down by 0.05" you could elimiate a lot of those corners.

5  Using Arduino / Project Guidance / Re: Use protoboard/perfboard in final product? on: January 16, 2014, 07:52:26 am
I used to make a lot of my own PCBs when I was younger and they nearly always needed something fixing due to my failure to convert the circuit diagram to a layout. With the advent of PCB CAD where the layout is built FROM the circuit, it's much easier to get something functional first time  - provided your circuit is right to start with.

The problems I have with the finished PCB these days are far more likely to be mechanical - stuff doesn't physically fit because I've used the wrong library part, mouting holes in the wrong place that sort of thing - but which most of is easy to check if you just print the board on paper first and try it out! The need for later revisions often come from changes that simplify or speed up assembly when doing a production 'run', but are not essential.

After getting over the hurdle of learing the PCB software (Eagle for me) I now really enjoy the layout process - I find it really theraputic, possibly to the point of obession when trying to get everything looking neat...

As a personal aside, if I was buying something and it turned up on perfboard, I'd be really disappointed! Especially if there was no indication up front!
6  Using Arduino / Project Guidance / Re: Adaptive Headlights on: January 08, 2014, 10:21:17 am
You may not be worried, but as another road user I am! How can you possibly know if your lights are "in the right position" while you are driving along and not dazzling other road users.

There's a reason things like this are checked in an MOT! If they are enforced by law, that is saying this is of sufficient importance that you should not be dicking about with it yourself!

7  Using Arduino / Project Guidance / Re: Adaptive Headlights on: January 08, 2014, 07:38:36 am
If you are in the UK, you probably want to first check how such a modification fits in with the MOT  - I could easily see fitting a homebuild device to the headlights would get you a fail.
8  Community / Website and Forum / Re: What's with the CamelCase on headings? on: October 04, 2013, 03:08:48 am
This seems to be a font / rendering issue on IE...
9  Using Arduino / General Electronics / Re: LED tutorial: "shorter anode pin should be connected to positive". Eh?! WTF? on: September 30, 2013, 07:42:46 am
I've always looked at the led itself look carefully and you see both the anode and cathode and the bonding wires, the little segment bonding wire larger segment, all of the 5mm / 3mm leds i've ever had has worked using this method the small block is positive, negative from the larger segment.

This is my rule of thumb too, but it's NOT foolproof. I have an 8mm red LED on my table right now that breaks the rule...
10  Using Arduino / General Electronics / Re: Two questions on simple PCB schematic on: September 25, 2013, 07:07:43 am
Cosmetically, I'd say keep the schematic connections horizontal or veritcal... And make sure you add a 'pip' at every junction (an ERC will pick missing ones up)
11  Development / Other Hardware Development / Re: Eagle - Many package connections to one device pin? on: September 11, 2013, 11:08:21 am
Not quite - I want to be able to connect to either of the hole pads on a layout by layout basis, and want it to know that they are electrically connected/equivalent without having to connect them myself via PCB traces.

From looking at what Sparkfun have done, I think it's safe to assume I can't.
12  Development / Other Hardware Development / Re: Eagle - Many package connections to one device pin? on: September 11, 2013, 07:35:06 am
Spoke too soon - the Append isn't quite what I needed since Eagle will still run a ghost wire between the two pads and expect them to be connected with a trace, whereas they are electrically connected on the physical device, so the trace is unnecessary.

I looked at the @ option too but that seems to require a symbol pin for each connected pad. The example I have is a battery holder, so obviously I want a standard 2 pin battery symbol for the circuit...
13  Development / Other Hardware Development / Re: Eagle - Many package connections to one device pin? on: September 11, 2013, 06:48:52 am
Ah yes - append what I needed - screamingly obvious when you know!
14  Development / Other Hardware Development / Re: Eagle - board holes in library parts? on: September 11, 2013, 06:36:16 am
15  Development / Other Hardware Development / Eagle - Many package connections to one device pin? on: September 10, 2013, 04:50:45 am
Another Eagle component library question - if you have a package that has several pins all connected internally together (multiple grounds for example) is it possible to connect these all to the same pin in the device / symbol?

The pins to pads connection process seems to be a one to one relationship. I tried renaming the pads to the same name but it won't allow that... is there any other trick?

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