PCB-production

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Here's some fun.

I had to grow the board slightly in width, but now you have a zero via solution - that is zero vias for signals. You do have an unbroken ground plane, however. I made two versions, one with the standard SPI pins, the other with alternate SPI arrangements, as in the initial layout.

alternative SPI.gif

Let me know what you think. :p
 

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I'm also at the point in my project where I have finished prototyping with my Teensy and want to move on to PCB. This will be my first PCB, and I just finished the (quite helpful) Sparkfun tutorial mentioned above. Unlike Frank, I'm not trying to include the entire Teensy in my PCB. Instead, I want to make a PCB that includes the components and pins I need from the Teensy and a few additional boards. I see that there is an Eagle Library for Teensy 3.x, but it only includes the Teensy itself, not the individual chips. Are there downloadable eagle files for the chips on board the Teensy, or do I need to make custom parts in eagle for each chip?

Edit: I saw I overlooked the libraries for MK20 and MINI54 on this page. Well, I saw them, I just didn't know what they were till I saw this related thread

Additionally, I have been prototyping with both the Teensy 3.1 and LC. My code works on both, and both include all the qualities my project requires. Do I understand correctly from the Teensy LC Schematic thread that if I were to try to create a PCB from the Teensy LC, the chips that are pre-programmed by PJRC would not be ready for a few months? That'd make my decision easier as to which chip I want to use in my PCB.

Thanks!
 
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Slight update. Decided to move to center 'trunk' for power, allowing both power pins to supply juice to the flash RAM. Additionally moved the GND plane on top around a bit, along with resistor to allow better decoupling of mux chip. Not sure if the memory chips should be decoupled or not.

memoryboard 2.gif

This unit features somewhat better spacing between components also. Pinouts are identical.
 

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I'm also at the point in my project where I have finished prototyping with my Teensy and want to move on to PCB. This will be my first PCB, and I just finished the (quite helpful) Sparkfun tutorial mentioned above. Unlike Frank, I'm not trying to include the entire Teensy in my PCB. Instead, I want to make a PCB that includes the components and pins I need from the Teensy and a few additional boards. I see that there is an Eagle Library for Teensy 3.x, but it only includes the Teensy itself, not the individual chips. Are there downloadable eagle files for the chips on board the Teensy, or do I need to make custom parts in eagle for each chip?

Glad you found the libraries. Please be very diligent re: layout and schematics. At first, make every connection, even the ones that you may not think you need and then modify from there. You don't want to end up hand-soldering corrections on a MK20 chip with 0.5mm pin spacing.

Additionally, I have been prototyping with both the Teensy 3.1 and LC. My code works on both, and both include all the qualities my project requires. Do I understand correctly from the Teensy LC Schematic thread that if I were to try to create a PCB from the Teensy LC, the chips that are pre-programmed by PJRC would not be ready for a few months? That'd make my decision easier as to which chip I want to use in my PCB.

Paul has stated several times that he's planning on transitioning the Teensy bootloader from the Mini54 at some point to the bootloading chip that he's using on the LC. Among other things, the LC bootloading chip is smaller and has fewer pins. Unlike the Teensy 3.x series, the LC bootloading chip does not feature a I2C connection to the main CPU. There are a few connections to allow SWD flashing of the main CPU and that's about it... well, besides the pads Paul uses to initially flash the bootloading chip... :p

Anyhow, the new bootloading chips are going to get rolled out in the future as Paul and Robin presumably create a flashing jig that allows them to quickly upload the secret sauce that makes Teensy so awesome. Thus, if you have an immediate need, I'd suggest you continue your designs based on the 3.x series.
 
Agree on the reliability of EAGLE. UI is not what should be expected these days.
Feerouter is highly recomendable and still available. Google for it and download the Java code. It's definitely worth it.
Another router which seems to be very good and not too expensive is electra by Konekt(Belgium). You may try it for 14 days.
I do small and demanding boards that include Rf sections up to 6 GHz. Routing the critical tracks by hand I do definitely appreciate the help of a autorouter for digital control lines. Treating it the right way the EAGLE autorouter does the job. However every time I have used it "because it's there" I ended up hoping they would improve it one of these days. Feerouter is a free available improvent I found some month ago.
 
Feerouter is highly recomendable and still available. Google for it and download the Java code. It's definitely worth it.

I thought it was not compatible with Java beyond version 6 and the author didn't want to continue maintaining it (besides being threatened by his former employer for alleged trade secret theft, which appears to be a frivolous charge). Did you find a updated version, and if so, where?
 
Wow, thank you Constatin, great.

If anyone is interested in these boards , I could order some more and at cost to pass. Then it will be cheaper for everyone (preferably Europe ).
Would it possibly make sense to add some more memory on the back ?
 
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Thanks to Eduardo, I now have a working copy of the Freerouter! I previously tried building it from the github source with Netbeans and so on, and failed once the appliance tried to run.

FWIW, the autorouter does have some quirks you need to be aware of. For example, if you define ground planes or power planes, it will happily connect to them, even if the board is a 2-layer board and signals have islanded / orphaned the power plane. I use Freerouter principally for inspiration or as a quick and dirty method to see if a hardware layout is efficient or not.

As for the memory board layout, this sort of stuff is fun for me. You've contributed a lot here, Frank, so I'm only too happy to reciprocate with the little I know.
 
For what it is worth, I personally like using diptrace (http://diptrace.com/download-diptrace/) for doing my layouts. I find it a lot easier to understand than Eagle. They have a free version that is limited(2 layers, 300 pins). I personally purchased a standard version of diptrace. I also have purchased a lite version of Eagle, which I sometimes use to when working with others, or to convert Eagle libraries into diptrace libraries.

For fabrication: I mostly use oshpark or seeedstudio.
I have in the past also used pcbfabexpress, but they are more expensive. I have also used another fabricator setup through diptrace which is more expensive than oshpark, but has the advantage the ordering works directly out of the diptrace program, so I don't need to generate gerber and drill files of the right names and settings, and put them into zip file, to send off to oshpark or Seeed...
 
Thanks Constantin and Frank - Seeing it done and cleaned up should be instructive, especially standard SPI version - a good starting point.

2 mem chips MUX free will meet my needs - though 2nd side with another CS/chip couldn't hurt.

No MUX and then adding 8pin I2C w/pullups and perhaps an i2c pinned OLED. I could drop on some SMD LED/Resistor pads too.

This PJRC version mounts the ILI9341 over the edge. https://oshpark.com/shared_projects/IWylNfzD I suppose Eagle can work backwards to edit from the Gerber files? Have to check if this ILI9341 w/SD design would call for changes.
 
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Hey defragter, just be cognizant re: how you want to stack stuff. You can use the online gerber viewer or gerbv to see how big Paul's board is, but you also have to consider how the power jack will stick up higher than most pin headers have room for (unless you double-stack or place your board 'below' Pauls board).

My power meter master board (i.e. the one hat does the SD writes as opposed to the power chip reads) is shaped to accommodate the Si7021 humidity chip below. Another board that is designed to stack on top of the master board has a cutout for the vertical SDHC card holder on the master board, etc. Yet another optional board on top of that is even smaller. It's almost as if I'm trying to build an empire-style building... :p
 
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Thx Constantin - DeFroster - good one ;-) Stacking and clearance a worthy note. Indeed yesterday using Gerbv I get a nice look at Paul's board - easier for me to 'see' than the typical screen shots (or top&bottom) since this is new to me. I didn't install Eagle yet to start looking at my own efforts - or to convert your board to Gerber.

Frank's board looks good, Paul's initially for reference. Then on Paul's board: First it seemed the power part could go then I looked at Dual LiPo holders to connect instead of the Barrel Jack **.

Since the SPI pins are there on the bottom to route to a memory chip - and dropping a SOIC 8 (.154") I2C up top in the open space #18/19? You mention SD - since that can work from the ILI9341 now maybe I need SPI header space for that too - then I wouldn't need an 'empire' of more layers. Paul's board could rotate 180° under the ILI9341 for a taller shorter package.

Maybe header pin holes to mount Serial #0/1 for Debug or ESP8266 - and an i2C oled for when ILI9341 is too much.

** It would not be self charging - but the twin 18650 trays are $1.20 at Amazon and 2-3Ah * would be portable and run a long time even with an ESP8266. Or for $1.50 and ~700mAh with (2) 14500 cells in AA size - with a switch from Sparkfun and a JST connector

Question: Are the Swiss round/machine pin headers bad for any reason? They are much more compact.
 
I need some help !
I want to create a small circuit board . What software do I need , and which is suitable for beginners ? I have some practice with breadboard PCBs .
The board is about as large as the Teensy be and place some SOIC8 ICs (SPI-Memory + logic for CS) to it, on both sides, eventually ( For smaller packages my eyes are suboptimal ) .

How much does something like that cost in the production ? For 10-20 pieces ?
Anyone for a beginner like me to help ? :)
I'm a little late to the party, but if you plan on making larger boards than the "free" tools mentioned here, consider the opensource solution, gEDA, http://www.geda-project.org/. There's a mailing list where the guru's hang out and I seldom meet a group of people who are as helpful as they are. Of course this forum and the people on it are outstanding also.

The tools have a few warts the most glaring being that the schematic drawing tool and the pcb layout tool don't share a common set of keyboard and mouse controls, but the tools work quite well and there are more symbols and footprints available than you can shake a stick at. Also there are a number of tools that will let you design your own. I've been very happy with it. Of course, it runs best on an open source operating system too (Linux). :rolleyes:

Jim.
 
Thx Constantin - DeFroster - good one ;-)

What a lovely auto-correct fail. Apologies! :-D

I use the Yamaichi PTH Micro SD card holder in my designs because I like its board orientation (vertical) and ease of installation (PTH). However, it adds considerable height, which may or may not be objectionable to your purposes.

Question: Are the Swiss round/machine pin headers bad for any reason? They are much more compact.
I think I may have switched to those recently? The principal appeal to me is that these pins are much stronger than the usual flat stock you get from other pin header manufacturers and you can easily make multi-layer assemblies because they use pre-scored breakaway headers that can be configured in any length up to 64 pins per row. Thus, unlike the Arduino headers, you are no longer limited to using only commonly-stocked 6-pin and 8-pin extended headers.

I also like how securely they fit into each other. The downside is that these headers typically are quite low-profile. So you have to pay attention to component height... or find an edition that can also act as a 'spacer' between layers.
 
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Finally, I decided for a change. The board now has space for 6x SOIC-8 storage. I now put the 3-8 decoder 74HC138 on it, a bus driver 74HC367 (just to be sure, because 6 * SPI + external devices is quite a lot), and at last it needed a small inverter.
I have ordered from OSH-park, I'm very excited about my first board. I hope I have not made a mistake, and it works!

Thanks again to all!

thumb_i.png thumb_i2.png
 
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Congratulations. I hope it all works out.
I've had a few boards I've done for work, but I find the quality of them from my end, goes up every time I draw something new. There's nothing quite like having boards in your hard that you designed yourself and are sitting there working.
 
Since we have spoken about professional autorouters in this thread I want to mention that electra from KONEKT is included (lim. to 250-pins) in the free version of Target3001. You can use it with EAGLE designs. Taget3001 itself seems to be interesting. However you don't even have to install it to get electra.
 
My Boards arrived. The quality is great, OSH-Park made a good job !
I will test them now.. I hope i made no mistake and they are ok. And I'm very curious how my webradio performs with 3/4 MByte RAM.
 
256 KB RAM is already working, but provisionally :

https://forum.pjrc.com/threads/28599-PCB-production?p=72983&viewfull=1#post72983

The difference is
a) more RAM,
b) the "address"-decoder (bin->decimal decoder),
c) a buffer for the bus
d) a nice board :)

The board for my radio will only get RAM. But it's also possible to use FLASH or EEPROM on this board.

Edit:
The logic works. Need to solder the RAMs now (not cheap :-( ) and write some lines of code...
 
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It turned out that I had swapped two pins in the schematic accidentally for three RAMs . Ok .. next attempt :)
 
That's what you get for not using my design. :p

If it makes you feel any better, I have boxes of bad PCBs... :confused:
 
That's what you get for not using my design. :p

If it makes you feel any better, I have boxes of bad PCBs... :confused:

:)
I just ordered new ones.
I can write my code now (for 3 chips) , so from this point of view its ok.
It's great that osh-park makes 3 of them for less than 5$, but i have to wait again 3.5 weeks (shipping to germany)
The price of a single 23lc1024 is 2.90 €...
 
That's the part number I was wanting the other day (p#45) : 23lc1024 - Digikey is $21 for 10 ( or $2.52 each ). At 1Mb each I see how it takes 6 for 768MB now and why you worked for 6! Glad at least 3 work - that is a bit of a wait.
 
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