Teensy 3.1 to Arduno Shield DIY Adaptor

Yep, looks good!

Question: one thing I debated with myself with on my own Arduino shield board, is if I should have on it a 3.3v voltage regulator. I for sure wanted one on my first board as I have XBee connectors and did not want to risk running XBee off of the Teensy itself... My current Rev has one, but if I do another rev of my shield board, wondering if it is really needed. My guess is that most shields who want 3.3 volts probably still use the 5V input and use their own VR? Looking at the other two shield boards up here, I don't think either of them do their own 3.3v. Note on mine I do have jumpers to select IOREF to be either 5v or 3.3v

Thoughts?
 
Yes, I'd have separate regulator as the 3.3V out from the Teensy3 is just 100mA (or so).
The 5V source could be other than the USB 5V feeding the Teensy. All depends on potential current loads in those shields: XBee S1 non-Pro is rather low consumption; XBee-Pro at full power do get close to 100mA, for a few mSec.
Motors, relays, big LED arrays, etc. all differ of course.

USB is supposed to be 500mA per port but often it is not.
 
Yes, I'd have separate regulator as the 3.3V out from the Teensy3 is just 100mA (or so).
The 5V source could be other than the USB 5V feeding the Teensy.

Yes, that's what I've done for my board. The VUSB is connected the 5V pin on the Arduino power header.

VUSB is also by default configured as the input to the LD1117v33 regulator. It can be disconnected by a jumper though, and a separate power supply >= 5V used instead to the Vin pin of the power header, which in turn feeds the LD1117v33.

USB is supposed to be 500mA per port but often it is not.

Of course, it can also be > 500mA if using something like a micro-usb phone charger as a power supply. But the 500mA poly fuse on the Teensy 3.x between the USB shell connector and the VUSB pin would limit what you can use even if more was available.

If more power than is available through VUSB is required, disconnecting VUSB and supplying power to the LD1117v33 from a separate source would be the option.

I like the idea of using a 5V supply in any case, simply to get 5V to the 5V pin on the power header at no extra cost. But, if this wasn't desirable, and (say) you wanted to use a 12V supply for some reason, the other option would be to add a separate LD1117v50 to the prototyping area, and feed the 5V power header pin via that.

Basically, you want flexibility on one hand, and a good, useable default set-up on the other. If you are prototyping, it's a good bet the 3v3 100mA supplied from the isn't going to be adequate. So a "good, useable default set-up" would include providing the extra capacity on the 3v3 rail in my books.

Edit: Added rendering of board design
 

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Yes I finally put it live, and was surprised with a few orders this morning:)
For voltage regulator I choose 6-14V input down to 5V-800mA, but there are a lot of regulators that can fit the size. There is a jumper which enable to connect the Teensy VIN to this regulator or leave it to USB power or other VIN. I thought with the space left for circuit it is easy to go from 5V to 3.3 with two resistors if needed.
 
Yes I finally put it live, and was surprised with a few orders this morning:)

Congratulations! Always nice to get those first orders. :)

If you don't mind me asking, are you getting orders for bare boards, partly assembled, or fully assembled?
 
Congratulations! Always nice to get those first orders. :)

If you don't mind me asking, are you getting orders for bare boards, partly assembled, or fully assembled?

Mostly fully assembled, but the sample is not yet representative!
 
I once put my own Teensy-Arduino adapter shield in limited production runs (we produce and populate PCB's) for internal use, but never made it commercial because the bidirectional level shifters didn't perform as expected. I did get a lot of calls of interest tho.

I've recently developed a new take on this board: the Teensy-Arduino crossover board. Simply put, it's a Arduino form factor board containing all the Teensy 3.1 components (making it perfectly compatible with the Arduino IDE and Teensy loader) and adding some features such as 5V analog in and high-power, low-noise 3.3V lines.

I have a couple of them lying around right now for testing purposes. I've tested them with a lot of Arduino shields and everything seems to be working as expected (a relief after endlessly debugging the level shifter design of the previous board). Because they have the exact same form factor as an Arduino Uno, they also fit in all existing project cases.

If interest is high enough and if Paul will let me, maybe I'll put these in larger scale production :) . I think I can produce them in medium volume at the price range of a regular Arduino Uno.
 
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Just an update to say I'm now selling the Teensy 3.x shield/carrier board from my website; here's a link if interested http://embeddedcoolness.com/new-rfx-carrier-board-pjrc-teensy-3-x-added/.

I was very pleased with how well the boards tested when they came back from the fab. I think this is in part testament to the underlying quality of the Teensy product... superbly designed and engineered. They just work.

Positive response so far! One existing customer from Sweden just bought 5 (and 5 Teensy 3.1s from OSH Park to go with them), which is heartening!

I'll try to get these listed on Tindie as well within a few days, time permitting.

The only thing I've been caught a bit short on is the stackable header sets... running low on those. A batch due to arrive from China soon, hopefully. In the meantime, if anyone orders those as an option, they may have to be mailed separately to the main order when they arrive.
 
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I am not sure how many up here are interested in my kitchen sink versions of the breakout boards for the Teensy 3.1 ;)

But on my one with Arduino headers (v0.1), I ran into an issue, where I believe my 3.3v VR was shorting out. In particular the 3.3v circuit shorted into the 5v circuit. I believe it was either due to how close the pads were to pads of nearby caps and the like and/or via under VR.
On one board, I simply cut the VR off of it, and ran a jumper from the 3.3v output of Teensy to the 3.3v circuit. ...

So I decided to update the board as a set of 5 boards is only like $30 from Seeedstudio... While at it I made a few other changes, like added the ability to simply jumper from teensy 3.3v output, so that VR is optional... Also changed buttons, back to the ones I used on other boards, better aligned the reset jumper... The new version of the board shipped from China today.

Over the last several months, there have been a few people who sounded interested, but the SMD components deterred them, so for the fun of it, I decided to see how hard it would be to build a version of the board with all through hole components. So I generated a version, without SMDs. Well actually I left one, which is optional diode for AX servo circuit, that helps minimize the possibility of spikes on AX buss damaging board... I did increase the length of the board, by something like .1 inch to make room for resistors...

Teensyduino-nosmd-001.jpg

Not that I currently need any more boards, but ordered a set to be fabricated to try it out. If anyone is interested, all of the design files are up at:
https://github.com/KurtE/Teensy3.1-Breakout-Boards
This includes the Diptrace design files, PDFs showing the schematic and board, 3D JPEG render from diptrace layout and excel file showing parts lists. Also zip files with gerber files that should work as is for either Seeedstudio and OSHPark.

FYI - it is up to you on how much or how little of these boards to populate. That is, you can populate the board with just a power connecter, 5v VR and 2 caps, and as many of the connectors as you need, example just Arduino headers, or just some 3 pin connectors... You can choose to populate the 3.3v circuit or use the pin from the teensy... Everything else is optional: Leds, speaker, AX circuit, Caps associated with 3 pin headers... Can go into more details if anyone is interested.

But just doing this to have some fun!
Kurt
 
KurtE, I would be interested. Do you have the project as a shared project at OSH park or seeedstudio?

I notice a whole bunch of holes for resistors. Is this voltage dividers for specific pins?

<edit>
One of the earlier posts in the thread asked for long pin headers for Teensy. I haven't seen any in units of 14. Dipmicro does offer the long pin headers in 20 and 40 pin groups that you could cut down to size: http://www.dipmicro.com/store/HDR20X1FL
 
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Hi,

As I mentioned the complete design files are up on on github. I have not created shared projects up on OSHPark or Seedstudio but it is possible. So far I am not sure it saves you much. You can simply download the zip file with the gerber information from github and on both sites it will ask for a file, which the zip files are setup to handle for either of those two sites.

Yes, I have voltage dividers for both sets of Power input pins. However if you don't wish to use them, you can either not populate those devices and/or I have two pin connectors setup for each optional thing like this, which is only enabled when you connect a jumper/shunt... You have a few different options on how to power the board. There are two sets of screw terminals, which one goes directly to the AX BUS, but can also jumper to other set. There is a 2nd set that can also jumper to the logic side. Likewise you can use the USB power. Turns out on my Trossen Robotics PhantomX Hexapod, to power the board, I instead, left the power going to a powered AX BUS hub and used an AX cable to connect back to the Teensy and used that to power the board.

For pin headers, my excel parts list still show the default sized Arduino headers. I have purchased some others from Samtec, which are too high. I think for these boards, I will get another set from Samtec which is not so high.
I belive the part numbes for these are: ESW-108-12-T-S (... 106 ...) and (... 110 ...) for the 8 pin, 6 pin and 10 pin connectors. I wish someone actually stocked these, but can order directly from Samtec.

Kurt
 
Hi,

As I mentioned the complete design files are up on on github. I have not created shared projects up on OSHPark or Seedstudio but it is possible. So far I am not sure it saves you much. You can simply download the zip file with the gerber information from github and on both sites it will ask for a file, which the zip files are setup to handle for either of those two sites.
Kurt
I've not gone through the process on OSH to upload design files, etc. The stuff I've ordered from them have been shared design files. Exactly what files need to be uploaded?
 
Each of the Three main folders in this github project have a zip file in them:

Example on my machine, for the one with through hole components, I would upload:
C:\Users\Kurt\Documents\GitHub\Teensy3.1-Breakout-Boards\Teensy Shield Arduino Headers Through Hole\TeensyDuinoSimpleV001.zip

I tried to put some more information in the readme file about this.

Also I am playing around with the Excel parts list file in this folder, and added a 2nd page, which has the start of trying to show which parts are needed for what. So if someone decides that don't need/want some functionality, like AX servos, they can see which components they can drop from the board. I have not gone through all of the details and possibilities.

Example: You don't need a lot of IO pins. Well you can drop, the SMD pin adapter on bottom of teensy, as well as the IO pins and CAPS and...

Or: suppose in your case you are mainly going to use it with AX servos and use a powered AX Hub to power the board. In that case you don't need the screw terminal.

Also I choose a 5v VR which hopefully works with 6v NIMH batteries or 6.6v LifePO4 batteries as on some of my robots, I use these batteries as the servos only handle 6v. But on other setups, example AX servos or Orion Robotics servos, I may instead use a Lipo and as such can use some other potentially cheaper VR that drop out at 6.2v or 7v....

I will try to write up more in the readme file soon, about different options on populating boards.

Kurt
 
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