Teensy 3.2

[PaulStoffregen]

Paul, is the Minitan bootlader compatible with the new teensy 3.2? I mean since the new boot-loader is not ready for shipping yet.

No, the Mini54 implements only Teensy 3.0 and 3.1.

To implement Teensy 3.2, you'll need the new chip. It was supposed to be selling by now, and it is indeed coming in a matter of a few weeks. I know waiting can be painful, but if you can, I'd recommend holding out a few weeks. It really is coming soon.

 

[experion]

No, the Mini54 implements only Teensy 3.0 and 3.1.

To implement Teensy 3.2, you'll need the new chip. It was supposed to be selling by now, and it is indeed coming in a matter of a few weeks. I know waiting can be painful, but if you can, I'd recommend holding out a few weeks. It really is coming soon.

Thanks for your prompt answer. You have accomplished something really great with the Teensy 3 and above, nothing appears to come close of similar size.

We designed a custom PCB based on the teensy 3.1 and the Teensy audio board. The audio board was needed because Teensy audio library does not allow a second audio input. When this is done, it would make a lot of difference in the use of teensy for audio small audio devices. It would definitely make a difference to us.

My enquiry is:

(a)Can you make the teensy 3.2 part list available on the Teensy site. maybe as a kit...

(b) Not sure if this is already available, is it possible to provide the Teensy 3.1 and 3.2 Eagle files. This helps avoid potential errors in the design of custom PCB., especially on BOM and footprints.
There was an issue that arose because the Teensy 3.1 schematic had the 16MHz crystal without capacitors. However, my designer added the capacitors because a crystal guideline advised to use capacitors. This lead to some confusion with the PCB house and sorting out the BOM.

Hence why it would be great to get a clearer instruction on using the teensy 3.1 and 3.2 for custom design.

(c) If it possible to add the second audio input to the Audio library without the teensy audio board?

 

[Constantin]

I don't speak for Paul, but I know he doesn't use Eagle. I have published the eagle files for the processor and the mini tan boot loaders. I believe frank also published a known good eagle layout file with all the connections. IIRC, his uses a two layer board, whereas the Teensy 3.0-3.2 are based on a four later board.

Depending on how much coffee Paul wants to consume, it is possible that he'll accomplish the 3++ with a 4 layer board but my guess is that 6 layers will be required to route all the necessary BgA connections.

Elsewhere, people have figured out most of the components used. The schematics are a great place to start, however.

 

[PaulStoffregen]

I have published the eagle files for the processor and the mini tan boot loaders. I believe frank also published a known good eagle layout file with all the connections.

Did I make links to all these, from here?

http://www.pjrc.com/teensy/eagle_lib.html

If there are more I haven't linked, please let me know and I'll update the page.

Depending on how much coffee Paul wants to consume, it is possible that he'll accomplish the 3++ with a 4 layer board but my guess is that 6 layers will be required to route all the necessary BgA connections.

Yes, it's going to be 6 layers.

I recently got a quote from our PCB vendor. In volume, 6 layers is only a modest increase in cost over 4 layers. In fact, the estimated increase in PJRC's cost for a year's worth of Teensy++ 3.x PCBs (just the extra cost of increasing from 4 to 6 layers) will probably end up lower than what we spend on coffee over a year!

But then, I do drink quite a lot of coffee and Robin buys Illy medium roast beans....

 

[Frank B]

I believe frank also published a known good eagle layout file with all the connections. IIRC, his uses a two layer board, whereas the Teensy 3.0-3.2 are based on a four later board.

Not me....

 

[dpharris]

Is there an Eagle library for the 3.1 and 3.2?
Thanks
David
PS -- my 3.2s are ordered from Oshpark ... the day after your announcement!

 

[Theremingenieur]

Ordered two of the 3.2 today at Diigiit Robotics Europe
I will already build two prototypes with slightly reduced functionality before I switch over to the MK66 whose 2nd DAC is needed for complete operation. But this will already allow me to check and optimize my input circuitry. If everything works as expected, I'll publish a new FreqMeasure library (which I will call PeriodMeasure because it seems more logical to me), allowing input capture on multiple FTM channels.

I feel like apart from the 2nd DAC, the MK66 will be some overkill since I'll make no use of the FPU. I learned handling that with pseudo-integers and am up to now satisfied with the result.

 

[sumotoy]

ordered 3 some min ago at PIJRC shop, but noticed only now that it's actually out of stock!

 

[PaulStoffregen]

Opps, that's a mistake. There's *plenty* of Teensy 3.2 in stock!

 

[sumotoy]

Ah, feel much better now...

 

[Theremingenieur]

Mine arrived today!

 

[Constantin]

Did I make links to all these, from here?

FWIW, here is my latest Eagle library for the bootloaders (MiniTan and MKL02/MKL04) as well as all MCU footprints. Additionally, I have come up with new footprints of the boards themselves. This attachment covers the Teensy 3.x and LC series.

View attachment Teensy_3_and_LC_Series_Boards_v1.4.zip
View attachment Teensy_DIY_v1.0.zip

I will try to update all my previous footprints. The board files cover a number of variants, from all-pins and pads to simple DIL packages for folk who need the center 'tunnel' for GPIO traces.

In fact, the estimated increase in PJRC's cost for a year's worth of Teensy++ 3.x PCBs (just the extra cost of increasing from 4 to 6 layers) will probably end up lower than what we spend on coffee over a year! But then, I do drink quite a lot of coffee and Robin buys Illy medium roast beans....

No wonder you manage to answer questions at all times of day!

 

[cartere]

Speaking of coffee

My latest project, will control grinder when finished.

 

[Constantin]

That's great! Can it brew it and bring it to you too?

 

[defragster]

Paul: Still on the SparkFun Teensy 3.2 page - they missed the whole point of the supply upgrade on the T_3.2:

Also, it can provide system voltage of 3.3V to other devices at up to 100mA.

 

[KurtE]

I know that it may be a semi-niche product usage, but I wish that I could use either the LC or 3.2, directly powered by a 3s lipo battery. This is one reason why I know that at least a few people are instead using something like an Adafruit pro-trinket (http://www.adafruit.com/products/2000) and I would hate to have to back to an Atmega...

For example one might want to plug the Teensy into a Robotis Dynamixel servo chain like an AX-12, and have the Teensy listen on the Dynamixel Serial chain (Half duplex 1mbs) and either monitor some sensors and/or control some devices...

 

[defragster]

It looks like the trick to LiPo power on the Trinket is this shield. Like the onehorse addon for Teensy it powers from a LiPo that it charges from USB when plugged in. There a higher charger current version now too - neither are mass produced, nor quite as big and nor as cheap.

Of course a few mA may go farther on the lower power trinket. That Trinket Shield wouldn't mate to a Teensy - but seems it should wire up okay?

 

[KurtE]

Thanks defragster: But if I am not missing something those are to connect up a 1S lipo (3.7v), the AX Servos typically run on 3S lipo or about 11.1vs, which is higher than the VR on the Teensys are rated for. Looking at the Pro Trinket, it looks like it can handle up to 16v.

Obviously I can run a Teensy with a small external BEC, but that adds weight and complexity. Again just sort of a wish list type of thing

 

[defragster]

KurtE - you are right on both: "Up to 16V input". That is easier with lower current draw. PJRC DeRates the T3.2 due to the heat for anything near 10v its LDO might take when taking advantage of the current near/over 250mA it can produce. In your post I saw LiPo - and the Trinket is advertised with that LiPo addon. I didn't under stand you meant LiPo 'pack' (3s?) to get the voltage needed for the AX-12 servo 'thing' (I didn't recognize that for what it was).

 

[macaba]

FWIW, here is my latest Eagle library for the bootloaders (MiniTan and MKL02/MKL04) as well as all MCU footprints.

This really does not matter but I figure you might want to fix this in a future version:

"This is a footprint for the MK20dx256VHL7"
should be
"This is a footprint for the MK20dx256VLH7"

 

[akkotaire]

I understand the regulator on the teensy 3.2 is rated 10V max. But I need to supply the setup with a 3s lipo (so 11.1V to 12.6V). Since I will be using very little current could it be ok ?
Thanks

 

[PaulStoffregen]

First, make sure you've cut the VUSB-VIN trace. That last thing you want is for 11 volts directly from a battery to connect to a USB cable and damage an expensive computer!

The voltage regulator is Texas Instruments part LP38691. If you read the datasheet, section 7.1 " Absolute Maximum Ratings" on page 4 says "V(max) All pins (with respect to GND)" is -0.3 to 12 volts. The first footnote explains:

(1) Absolute maximum ratings indicate limits beyond which damage to the component may occur. Operating ratings indicate conditions for
which the device is intended to be functional, but do not ensure specific performance limits. For ensured specifications, see Electrical
Characteristics. Specifications do not apply when operating the device outside of its rated operating conditions.

Of course, TI recommends only using it up to 10 volts.

Also, please consider the Teensy 3.2 PCB is capable of dissipating about half a watt of heat from the regulator. At half a watt, it runs pretty hot, but still well within the regulator's capability.

If you have 12 volts input and 3.3V output, that's 7.8 volts across the regulator. If Teensy draws 35 mA, the result will be 0.3 watts. Even small increases in current on the 3.3V line result in pushing closer to the 0.5 watt maximum recommendation.

So in terms of your question "could it be ok", anything over 10 volts is pushing your luck and going over 12 volts is very risky, and even Teensy's normal current draw puts you close to the maximum heat the PCB can dissipate, so there's very little margin to power anything else from that 3.3V power.

I certainly wouldn't sell a product built this way, nor would I install such a thing in an unattended difficult-to-service location... but for a one-time project with an urgent deadline (something like a trade show demo), I might risk it. There's no question this is risky, so you'll have to make your own judgment call.

 

[Theremingenieur]

Just try it out... A teensy 3.2 costs only 20 bucks... ;-)

I don't know how much current the teensy itself draws, but if there are no peripherals to source from the internal voltage regulator at the same time, you should have some headroom.

Edit (after seeing what Paul has posted in the meantime while I was writing):
Why not put an ordinary 7806 or 78L06 in-between?

 

[akkotaire]

Thanks for the detailed reply, I will plan to add a regulator in between.
For a student 20$ makes a difference ;-)

 

[Theremingenieur]

For a student 20$ makes a difference ;-)

Please accept my apologies, I didn't mean to sound arrogant in whatever way. When I wrote about "only" 20 bucks, it was comparing to the Mafia-duinos, which are less powerful and more expensive, at least here in France.