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Topic: PCB board drawing (Read 3683 times) previous topic - next topic

magnethead794

#30
Dec 12, 2011, 08:16 pm Last Edit: Dec 12, 2011, 08:21 pm by magnethead794 Reason: 1

Ok, let me mull over this tomorrow and play with it.  As for the cost of the board, how quickly do you want it done?  If you don't mind waiting, you can get ten (10) 50mm x 50mm boards for $9.90 + s/h.  It just takes upwards of two weeks to get.


I just have to have this done by next February

Quote
Personally, I prefer not to have breakout boards hanging off of the edges, I'd rather place them over an open area on the main board for support.  But we'll see what I can come up with.  The majority of the space will be taken up by the Mini as it is.


They're going on female pin headers. Support won't be a problem. They're very stable right now. -> http://www.sparkfun.com/products/743

4050 has 16 pins
Arduino Mini has 35 pins
DS1307 has 5 pins (only 4 are used)
BMP85 has 6 pins (only 4 are used)
HH10D has 5 pins
Bluetooth has 4 pins (connected by wire header, must be off-board)
each regulator has 3 pins

= 71 pins total.

Assuming break-out-ability of all 35 pins on arduino, that's 106 through-hole's in the board.

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Another question, you want everything to be through hole, right (since you mentioned you already have it working on breadboard, I'm assuming you're just going to transfer from one to the other)?


Correct


If it were feasible, I'm thinking that one way to do it, would have arduino on one side of the board, 4050 on other side. Alot of traces would be crossing on separate layers, though. I'd have to draw it out by hand to see how it would work together. Theorietically moving pins 8 and 9 to 10 and 11 would un-cross a few lines. Even more theorietically, since I can assign the pins, I could flip them over backwards to make it easier.
KF5RVR

magnethead794

#31
Dec 12, 2011, 09:57 pm Last Edit: Dec 12, 2011, 10:17 pm by magnethead794 Reason: 1
Okay, you say 50mm square, I'm assuming that's 17 pins square. If so, I've got something that will work. Give me a minute to triple check it and then I'll upload.

The 4050 and Logic Level are both upside-down on the bottom of the board. Logic Level is flipped horizontally, 4050 flipped vertically.

Maroon is 3.3V
Red is 5.0V
Pink is 9.0V
Black is Ground (Ground Plane)
Dark Green is Data Layer 1
Light Green is Data Layer 2
Light Blue is frequency output of HH10D
Brown is reset pin (connected from the top of the board)
Digital 9 is written HIGH to power high side of Logic Level

Maroon, Red, and Dark Green, Dark Grey are on Layer 1

Light Green, Light Grey, Light Blue are on Layer 2.

I assume this is possible-> the filled circles where lines change color means there's a hole there, that links the 2 layers together for that trace.

Pins that I dropped off the Mini:
Left Reset
Digital 3
+9V
Top +5V
Top Rx
Top Tx
Top IO7

KF5RVR

KirAsh4

Here's the thing, you should not worry about having traces exactly 0.1" apart.  Traces can be as close as 6mils (4mils for some, more expensive fab houses.)  So that makes for a very tight design.

Also, traces can cross each other.  If both traces must start and end on the same layer and they cross each other, simply punch one down to the bottom layer and keep going till you get to the destination and punch it back to the top.

This is where a schematic becomes very very helpful.  If you create your schematic in Eagle, it can route it all for you automatically.  You don't have to do anything (for the most part).

And if you put the Mini on header, you have space below it, between the headers, to put the shifter.  It doesn't need to go on the underside of the board.  There are so many things you can achieve, but you need to start with the schematic first.  Let me work on that and I'll show you ...

magnethead794


Here's the thing, you should not worry about having traces exactly 0.1" apart.  Traces can be as close as 6mils (4mils for some, more expensive fab houses.)  So that makes for a very tight design.

Also, traces can cross each other.  If both traces must start and end on the same layer and they cross each other, simply punch one down to the bottom layer and keep going till you get to the destination and punch it back to the top.

This is where a schematic becomes very very helpful.  If you create your schematic in Eagle, it can route it all for you automatically.  You don't have to do anything (for the most part).

And if you put the Mini on header, you have space below it, between the headers, to put the shifter.  It doesn't need to go on the underside of the board.  There are so many things you can achieve, but you need to start with the schematic first.  Let me work on that and I'll show you ...


I couldn't think of a logical way to fit the shifter under the mini. If you can, that's great.

My CAD works on 0.1" increments, so that's what I have to work with. I can't draw 'between the lines'
KF5RVR

KirAsh4


My CAD works on 0.1" increments, so that's what I have to work with. I can't draw 'between the lines'

I believe it's time you start spending some time playing with Eagle. :)  There are plenty of instructions online, as well as youtube videos.  SparkFun also has instructions on their site.

I'll leave you to do that, and I'll work on this design here for you and I'll send you the files when done so you can open them yourself and see how they look in Eagle.

KirAsh4

#35
Dec 13, 2011, 01:37 am Last Edit: Dec 13, 2011, 01:43 am by KirAsh4 Reason: 1

74HC4050 IC Shifter (NOTE: cannot use connections as given on linked page. See below)
The 4050 is set up to use pins 3, 4, 5, 6, 7. Due to the HH10D, this cannot happen. I am using 2, 3, 7, 8, and 9 instead.

I still need to see the datasheet to see what you're talking about.  Which pains do you have paired up, etc., etc.  And is it a 4050 specifically?  There are several versions in the 405* series ... that's why I ask.

magnethead794

#36
Dec 13, 2011, 02:04 am Last Edit: Dec 13, 2011, 02:07 am by magnethead794 Reason: 1


74HC4050 IC Shifter (NOTE: cannot use connections as given on linked page. See below)
The 4050 is set up to use pins 3, 4, 5, 6, 7. Due to the HH10D, this cannot happen. I am using 2, 3, 7, 8, and 9 instead.

I still need to see the datasheet to see what you're talking about.  Which pains do you have paired up, etc., etc.  And is it a 4050 specifically?  There are several versions in the 405* series ... that's why I ask.


The freqCounter library is specifically on Digital5 for the frequency output of the HH10D, so this interrupts the default configuration of the 4050 library into the Arduino. The 4050 library is easier to navigate, so I edit what pins it talks to.

Since the setup uses pins 1, 2, 3, 4, 5, 6, 7, 8, 11, 12, 14, 15 the 1-8 side is dominate. So on the same side of the IC, we have 3 outputs and 5 inputs. Makes it hard to set it up around the Mini without getting blocked paths. That's why I was just going to keep it simple and have it on a separate shield.

I'm on OSX and I'm just lost in eagle. I have Eagle 5.11.0 Light. I get the tools on the left, but just a blank screen otherwise. No coordinates or anything. I was hoping for at least a coordinate grid or something for a novice like me to understand. Screenshots of FreePCB show that at least it has a better novice UI, but they don't have an OSX version.

On the IC:

HEF4050BP LQE7x6-05 UAG10977
KF5RVR

KirAsh4

You're missing components in your circuit by the way.  Both the LDOs need capacitors around them, which you don't have.  I'll put them in as TH packages and get some part numbers for you as well.

magnethead794


You're missing components in your circuit by the way.  Both the LDOs need capacitors around them, which you don't have.  I'll put them in as TH packages and get some part numbers for you as well.


yes they are there. That's why each LDO has 5 pins. perhaps I forgot them in the drawing? I suppose so.
KF5RVR

magnethead794

#39
Dec 13, 2011, 02:42 am Last Edit: Dec 13, 2011, 02:47 am by magnethead794 Reason: 1
I work on race cars...Electronics isn't my strongsuit [yet]. That said, here's what the fully working version looks like on breadboard:











KF5RVR

KirAsh4

Oh, I didn't realize that's what the holes were there for.  You didn't have them listed in your parts list, so I assumed you didn't have them.  Nevermind!

magnethead794


Oh, I didn't realize that's what the holes were there for.  You didn't have them listed in your parts list, so I assumed you didn't have them.  Nevermind!


I think I hap-hazardly left them out on the last drawing.

I also have a .1uF cap across the +/- input for filtering. I can't see it making a difference on the battery, but on my wall wart it might be achieving something.
KF5RVR

KirAsh4


The LCD is on the other end of a 16 ft DB9 cable. So the respective pins just need to be headerized.

RST (reset) pin of the LCD (orange wire) to pin 2 of the 4050
CS (chip select) pin (yellow wire) to pin 4 of the 4050.
D/C (data/command) pin (green wire) to pin 6 of the 4050
DIN (data in) pin (blue wire) to pin 15 of the 4050
CLK(clock) pin (purple wire) to pin 12 of the 4050.

You don't say if it needs power as well ... 3V3?  5V?  GND?


I think I hap-hazardly left them out on the last drawing.

I only see holes for one cap ... each LDO needs two caps, one on the input and one on the output.


I also have a .1uF cap across the +/- input for filtering. I can't see it making a difference on the battery, but on my wall wart it might be achieving something.

It's good to always have one.

magnethead794



The LCD is on the other end of a 16 ft DB9 cable. So the respective pins just need to be headerized.

RST (reset) pin of the LCD (orange wire) to pin 2 of the 4050
CS (chip select) pin (yellow wire) to pin 4 of the 4050.
D/C (data/command) pin (green wire) to pin 6 of the 4050
DIN (data in) pin (blue wire) to pin 15 of the 4050
CLK(clock) pin (purple wire) to pin 12 of the 4050.

You don't say if it needs power as well ... 3V3?  5V?  GND?


I think I hap-hazardly left them out on the last drawing.

I only see holes for one cap ... each LDO needs two caps, one on the input and one on the output.


I also have a .1uF cap across the +/- input for filtering. I can't see it making a difference on the battery, but on my wall wart it might be achieving something.

It's good to always have one.


LCD is 3V3

I only have one cap on each LDO, as per the data sheet (between Vout and GND on each one). Then I have the .1uF between +9 and GND (which might be the sufficient input cap?)
KF5RVR

KirAsh4

No, each LDO need the caps on both sides.  They might not end up near where the 0.1uF that you have across Vin and GND, so you always add them.  I'll add VCC3V3 and GND for the LCD.

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