Teensy 3.2

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Paul

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Today we're happy to release Teensy 3.2.

http://www.pjrc.com/store/teensy32.html

Version 3.2 is a minor upgrade to Teensy 3.1. The main change is an improved 3.3V regulator, to allow Teensy to directly power ESP8266 Wifi, WIZ820io (W5200) Ethernet, and other power-hungry 3.3V devices.

We're specifying Teensy 3.2's power output at 250 mA and the maximum voltage input at 6 volts, due to PCB thermal dissipation limits. However, the actual regulator chip is capable of up to 10 volts input, and up to 500 mA output. These higher limits are intended to allow Teensy 3.2 to be more rugged when used with non-USB power sources which aren't well regulated 5 volt sources.

Teensy 3.2 is fully compatible with all shields and add-on boards designed for Teensy 3.1. It preserves the same size, pinout, and processor as Teensy 3.1.

The bootloader chip is also changed from Mini54 to KL02 (the same as Teensy-LC). A full schematic is available:

http://www.pjrc.com/teensy/schematic.html
 
I wish you had included a 74LV1T125 on 3.2. I really like that feature on teensy-lc! But beeing a dirrect replacement for teensy 3.1 and that there is not much space left on teensy I can understand why not.
 
Today we're happy to release Teensy 3.2.

http://www.pjrc.com/store/teensy32.html

Version 3.2 is a minor upgrade to Teensy 3.1. The main change is an improved 3.3V regulator, to allow Teensy to directly power ESP8266 Wifi, WIZ820io (W5200) Ethernet, and other power-hungry 3.3V devices.

We're specifying Teensy 3.2's power output at 250 mA and the maximum voltage input at 6 volts, due to PCB thermal dissipation limits. However, the actual regulator chip is capable of up to 10 volts input, and up to 500 mA output. These higher limits are intended to allow Teensy 3.2 to be more rugged when used with non-USB power sources which aren't well regulated 5 volt sources.

Teensy 3.2 is fully compatible with all shields and add-on boards designed for Teensy 3.1. It preserves the same size, pinout, and processor as Teensy 3.1.

The bootloader chip is also changed from Mini54 to KL02 (the same as Teensy-LC). A full schematic is available:

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

ordered a couple of them.
 
Today we're happy to release Teensy 3.2.

http://www.pjrc.com/store/teensy32.html

Version 3.2 is a minor upgrade to Teensy 3.1. The main change is an improved 3.3V regulator, to allow Teensy to directly power ESP8266 Wifi, WIZ820io (W5200) Ethernet, and other power-hungry 3.3V devices.

We're specifying Teensy 3.2's power output at 250 mA and the maximum voltage input at 6 volts, due to PCB thermal dissipation limits. However, the actual regulator chip is capable of up to 10 volts input, and up to 500 mA output. These higher limits are intended to allow Teensy 3.2 to be more rugged when used with non-USB power sources which aren't well regulated 5 volt sources.

Teensy 3.2 is fully compatible with all shields and add-on boards designed for Teensy 3.1. It preserves the same size, pinout, and processor as Teensy 3.1.

The bootloader chip is also changed from Mini54 to KL02 (the same as Teensy-LC). A full schematic is available:

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

Many thanks for your precious work Paul ! may i put on the teensy 3.3 wish list a 12v capable regulator a canbus transcriver and i2c pullups ?
cheers !
 
Hey that's awesome!

So now that the Teensy 3.2 is released, do you guys have any plans for a Bed of Nails for the MKL bootloader chip? I'd love to use that bootloader chip, esp. if one chip can handle either a 3.2 or a LC MCU.

Also, for teensy DIY applications that do not envision USB host mode, I presume pin 4 on the USB connector can continue to be ignored and PTA6 pin on the KL02 and the PTA1 pin on the MK20 can be left floating? I presume this is the case but wonder if the two (MKL02/PTA6 and PTA1/MK20) can be left to float by themselves or if they require a connection between the two even if USB host mode is not wanted?
 
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Nice incremental update. Maybe those vias around the KL02 will make hacking in SWD easier.
 
So now that the Teensy 3.2 is released, do you guys have any plans for a Bed of Nails for the MKL bootloader chip? I'd love to use that bootloader chip, esp. if one chip can handle either a 3.2 or a LC MCU.

Yes, this is planned.

This weekend I built the programmer, but unfortunately we had a mishap here which damaged the ZIF socket. I've got another socket on order yesterday. It's a special part that takes a few weeks to get.

This definitely is coming. The chip will be available in 2 sizes, the extremely small 3 mm QFN, and a large 7 mm TQFP with "easy" 0.8 mm pitch pins.

It will automatically detect if you've connected a MK20 or MLK26 and implement either Teensy 3.2 or Teensy LC. Later when we add a 32 bit Teensy++, the firmware will be updated to automatically detect the MK66 chip too.
 
The bigger button looks appealing! Can heat sink be added to improve voltage regulator chip thermal dissipation?
 
Thank you so much. I will revise the next turn of the board for the new chips. Progress has been so slow.... (argh!)

How about the question re: Pin 4 and separate floating pins vs. joining MKL02/PTA6 and PTA1/MK20 but leaving the joined pair floating?
 
Can heat sink be added to improve voltage regulator chip thermal dissipation?

Maybe, but it'd be quite a challenge.

Perhaps the most effective location would be on the back side of the PCB. Two vias are located close to the regulator's thermal pad, which provide an all-metal path from the silicon.

On top of the chip would be the other possible place. There you've got the plastic package between the heatsink and silicon, but it still might be pretty effective at cooling. A huge challenge would involve the height of nearby parts, like the PTC fuse and 2.2 uF capacitors. They're taller than the chip. The heatsink would need to be extremely small (3 mm) or a special shape to avoid those nearby parts.

As with all heat dissipation, force air flow makes a dramatic difference. Crazy as as a fan may seem, if you're really needing more than 250 mA, maybe something else using that power is also warming up?

If you don't need too much more, you might also just give it a try, with Teensy oriented in different position (possibly with well placed vents, if inside an enclosure) to allow a little natural convection air flow. The 250 mA number we're publishing is pretty conservative. The assumption is we can't predict a lot of factors about how people will actually use Teensy. Odds are good slightly higher current can work fine in your application. I personally tested about 1/3rd of an amp with 5.1 volts input, resting horizontally exposed to open but still air, with pins soldered and plugged into a breadboard. It got pretty warm to touch, but nowhere near the chip's rated temperature.
 
Also, for teensy DIY applications that do not envision USB host mode, I presume pin 4 on the USB connector can continue to be ignored

Yes, there's no need to connect pin 4 on the USB if you'll never use host mode.

Whether host mode software is ever published is also good question. It might happen someday... but with the anticipated 2nd USB host-mode port on the upcoming Teensy++ board, investing a lot of time into host mode support on the main USB port is looking less and less likely.

and PTA6 pin on the KL02 and the PTA1 pin on the MK20 can be left floating?

I would recommend keeping that connection to the MK20 chip. Today it's unused, but I can't guarantee it will always remain unused by future firmware.
 
Enjoy it - general/shared consensus seems to be you earned it :)

Is this why OSH was out of Purple boards? Are they going to publish the 3.2 in Purple?

<edit>: order placed/shipped - now I have spare spares to last until the FPU version ships.
 
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Yeah, it's pretty awesome, addressing the most common failure mode while keeping the same form factor. The new board is packed to the gills!

Spent some time this AM to design a new board using the MK20 and the MKL02. Got it down to 2 jumpers/0 Ohm resistors/or vias to make it work on a 2 layer board.

Bottom.gif

I will be releasing a new set of libraries shortly with all bootloader chips (MiniTAN and MKL02). I have yet to put together the TQFP package for the MKL02, however..
 
How about a topside heat sink? 14ga(2mm^2) copper wire flattened (1x3mm) and shaped to cross over the back edge of the USB shell? Thermal paste on chip contact and soldered to shell should be stable and low profile.
t32heatpipe.jpg

With $3 shipping mine won't be here before Saturday.

>> opps: Expected Delivery Day:Friday, September 18, 2015 :( >> Saturday . . . .
 
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This is a heat sink, not a heat pipe. A tiny heat pipe for this application would be awesome, though I don't know where we'd get them.

A heat pipe is hollow and has contents that change phase. Also the interior is typically shaped to provide increased surface area over a simple pipe either by grooves or sintered metal power.
 
Dutifully corrected the nomenclature. My concern was if there was any risk in the design - and worth the trouble? With plastic shell and no nearby things to short, paste to mate and fill voids - don't want to make an antenna or such other issues. The sink mass seems significant enough and cheap/easy - especially if the usb shell gets involved. MarkII design rather than the vertical bend, the height difference might be better done with a flat top and the wire folded under to come down to the chip top. Flattened and shaped for contact - solder the side of bent under end to make sure the full bent piece won't fall free.
t32heatsink.jpg
 
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