Author Topic: My first Eagle SCH/PCB, review?  (Read 17349 times)

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Offline TriodeTiger

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Re: My first Eagle SCH/PCB, review?
« Reply #25 on: August 15, 2014, 09:45:55 am »
Homebrew thank you. I felt like crap basically, but in an inspiring way. I wasn't sure what I was doing and I after seeing some of the tricks you've used (a ground trace down the middle, etc.) I made this without basically referring to it again, and came up with something kinda similar. (I loved the feeling of reorienting things and seeing "this can go here, and this can be flipped, and this won't need to snake" like a puzzle!!)

E14's patchy stock can be berid of now, since they force upon me FedEx so digikey might as well be my distr. now. What connector did you use?

I notice my choice of some footprints will chagne when I find things to buy, the PTC is small, connector a default that is not in stock and other similar things for a 2am workup - but any big issues you guys can find?

The Via thing for the TP's were a little unfortunate, but I am glad I could get it all on the top side and include SMD. Maybe I'll convert those diodes to SMD?

Do you think this one's actually worthy of a complete novice's board done a little right?

edit: cool, comes to about $11 for 3 boards = $~4/board. Half the price of my other one, and no BS mosfets.
« Last Edit: August 15, 2014, 09:56:19 am by TriodeTiger »
"Yes, I have deliberately traded off robustness for the sake of having knobs." - Dave Jones.
 

Offline Refrigerator

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Re: My first Eagle SCH/PCB, review?
« Reply #26 on: August 15, 2014, 05:47:10 pm »
You could of easily have routed this on a single layer, for example GND trace could of gone under D1, and VIN could have gone around the back of the regulator.
Just started a blog at http://brimmingideas.blogspot.com/ . Not much in it as of now but more is sure to come :)
 

Offline TriodeTiger

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Re: My first Eagle SCH/PCB, review?
« Reply #27 on: August 15, 2014, 10:29:08 pm »
You could of easily have routed this on a single layer, for example GND trace could of gone under D1, and VIN could have gone around the back of the regulator.

Honestly, I thought: In a real product, there weren't be test points. So I wanted to test vias for the first time (dual side is free of charge with Laen of course) instead of doing exactly your suggestion.

I'll take that minor suggestion as a "there's nothing big left to pick on" :P

My next post shall be finding real parts on digikey, creating my BOM, fixing the footprints, and seeing what else I can optimise in the layout!
« Last Edit: August 16, 2014, 09:01:12 am by TriodeTiger »
"Yes, I have deliberately traded off robustness for the sake of having knobs." - Dave Jones.
 

Offline TriodeTiger

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Re: My first Eagle SCH/PCB, review?
« Reply #28 on: August 16, 2014, 09:56:06 am »
How's this all look? (tdocu is yellow, footprints confirmed)



Passes laen's DRU and also ERC (minus stop mask crap), and comes out to just $11 for 3 boards. Half of my old one.

Digikey's BOM is here: https://www.digikey.ca/classic/Ordering/ResumeOrder.aspx?WebId=113615235&AccessId=98969&help=true

(It seemed to work on another browser, but if not, ~$12 for parts for all three + $8 for shipping)

Not a stellar price at about $10/board combined, but for a low quantity of three boards, that's not too bad I think!

How's it all look? I know there's a few aesthetics, like the fuse maybe. The regulator's protection diode will not short on the heatsink, and thermally is no issue as it'll likely never conduct, at least not where it will matter if it is already heated a tiny bit. I like how it looks like a 'star' ground, and that the loops for each side (in-reg + out-reg) are circular and short.
« Last Edit: August 16, 2014, 09:58:49 am by TriodeTiger »
"Yes, I have deliberately traded off robustness for the sake of having knobs." - Dave Jones.
 

Offline Refrigerator

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Re: My first Eagle SCH/PCB, review?
« Reply #29 on: August 16, 2014, 07:03:24 pm »
You're getting better at this.  :-+
I personally like to make PCB layouts just for fun, i like taking all of my audio amp chips and make layouts for each one of them.
Just started a blog at http://brimmingideas.blogspot.com/ . Not much in it as of now but more is sure to come :)
 

Offline TriodeTiger

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Re: My first Eagle SCH/PCB, review?
« Reply #30 on: August 28, 2014, 04:39:21 am »
You're getting better at this.  :-+
I personally like to make PCB layouts just for fun, i like taking all of my audio amp chips and make layouts for each one of them.

Thanks!
A 555 gave me a headache trying to route! So I thought instead, I'd not only dabble in to SMD, but make my entire board SMD(almost):



I ran in to so many learning exercises.

A) Every -duino and clone seems to use a "PANASONIC D" footprint within the rcl library and that gave me an incredible headache trying to find what package they used (no one has real BOMs!). Noticing all their choices are different, I found out that most SMD radial cans at ~10-500uF have 6.3mm dia. I assume people just choose any one that fits in that footprint.

B) I wanted some margin (I expect no more than 100mA use), so I found D2PAK or TO-261 package regulators in the 200-500mA range and chose the D2PAK. The one I chose raises 92*C/W in air, and so under normal use (9V-in,100mA-out) = 400mW = ~40C increase, reasonable, but I thought I'd try to manage it.

I figured since I made such a nice single-sided layout I'd make some thermal relief vias (modifying smd->via clearance in the DRU) and add some basic planes underneath. Do you think that would be enough, to say reduce the temperature by at least 10 degrees? should I flood more or am I expecting too much (100mA+) out of a small regulator?

C) What are my hopes for doing this DIY? My ignorant thoughts are: Flux the entire board, give each pad (or one of each if they're to tack something on first) a flood of solder, and then go away at it with my hakko. thoughts? Or would a syringe and solder paste/hot air gun (I have a sparkfun heaterizer) be the way to go?

Any suggestions?

Here's my BOM, digikey seems to allow viewing of them:
http://www.digikey.ca/short/7cqqcm

I can probably optimise things a little more, but that is so far what I have and it looks pretty decent. I'm embarrassed (in a good way) about my OP's design now :P
« Last Edit: August 28, 2014, 05:02:06 am by TriodeTiger »
"Yes, I have deliberately traded off robustness for the sake of having knobs." - Dave Jones.
 

Offline Tac Eht Xilef

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Re: My first Eagle SCH/PCB, review?
« Reply #31 on: August 28, 2014, 10:44:05 pm »
A) Every -duino and clone seems to use a "PANASONIC D" footprint within the rcl library and that gave me an incredible headache trying to find what package they used (no one has real BOMs!). Noticing all their choices are different, I found out that most SMD radial cans at ~10-500uF have 6.3mm dia. I assume people just choose any one that fits in that footprint.

Tip: the footprint of those in the default RCL library (and most others you'll find around e.g. SparkFun) seems meant for reflow, not hand-soldering. To avoid further incredible headaches when hand soldering, either create custom footprints with extended pads & solder mask opening, or simply use the next size up (e.g. 6.3mm->8mm) so you've got some pad you can actually get your iron to...
 

Offline TriodeTiger

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Re: My first Eagle SCH/PCB, review?
« Reply #32 on: October 21, 2014, 02:00:20 pm »
Tip: the footprint of those in the default RCL library (and most others you'll find around e.g. SparkFun) seems meant for reflow, not hand-soldering. To avoid further incredible headaches when hand soldering, either create custom footprints with extended pads & solder mask opening, or simply use the next size up (e.g. 6.3mm->8mm) so you've got some pad you can actually get your iron to...

Whoops, forgot to update. The free shipping option really does "(may) take 21 business days" - arrived on the final day before I would get worried.

Here's the board:


I notice, although the silkscreen was wasn't marred like my last revision's (although I scanned the least marred one), in this one they've botched the sizing of my text on the left (why switch my font? it's not a silk-stamper, it's a silk-screener!). Also, it's another shade of purple. Not as professional as I thought, but, hey, neither am I.

But other than that, it looks quite spectacular, I seem to learn quite differently, then quickly, at least.

I guess I can muck around with flooding some of the more difficult pads with solder and using my trusty heat gun to work it on there (i.e. the radial can caps) but I've seen people do the same on similar boards with only a soldering iron.

Whenever I get more money and motivation I'll do the Digikey run and smack myself for not making something more useful or fun like something blinky or a random number generator decider or somethin'  :palm:  I love the idea of using a transistor for a TRNG and feed that in to something. I'm a nerd that way.
« Last Edit: October 21, 2014, 02:10:23 pm by TriodeTiger »
"Yes, I have deliberately traded off robustness for the sake of having knobs." - Dave Jones.
 

Offline gonzoid

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Re: My first Eagle SCH/PCB, review?
« Reply #33 on: October 21, 2014, 03:43:04 pm »
I notice, although the silkscreen was wasn't marred like my last revision's (although I scanned the least marred one), in this one they've botched the sizing of my text on the left (why switch my font? it's not a silk-stamper, it's a silk-screener!).

Hey TriodeTiger,

I'm not sure if it has already been pointed out on the thread, but it is preferred to use vector fonts in order to get "WYSIWYG" silkscreen and soldermask texts from your layout to your physical board.

You can check how it can be done on this Sparkfun tutorial: https://www.sparkfun.com/tutorials/109
 

Offline TriodeTiger

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Re: My first Eagle SCH/PCB, review?
« Reply #34 on: October 21, 2014, 08:22:59 pm »
I'm not sure if it has already been pointed out on the thread, but it is preferred to use vector fonts in order to get "WYSIWYG" silkscreen and soldermask texts from your layout to your physical board.

It just looks flashy some places, but it seems they've rendered it as vector, so I guess proportional is some sorta meta-sizing or something. Haven't really looked in to what it is proportional to. Well, that's what tests are for :P Thanks.
"Yes, I have deliberately traded off robustness for the sake of having knobs." - Dave Jones.
 


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