Teensy 3.2

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Why did you change the bootloader chip?

Presumably, one bootloader chip to rule them all... as the MKL02 can be programmed to support all Teensy MCUs (3.2, LC, and the upcoming 3++).

The MKL02 is smaller than the 4x4mm version of the MiniTAN54, allows the retrofit of the external voltage regulator on the Teensy 3.x series boards.

Also, one less bootloader chip for Paul to maintain?
 
Why did you change the bootloader chip?

Mainly because the Mini54 is terrible. Back in early to mid 2012, when Teensy 3.0 was developed, the Mini54 and a NXP part were the only viable options. The NXP part was prohibitively expensive.

The KL02 chip is superior in every way, except it didn't exist until mid 2013. Even after it was "released", Freescale didn't ship production volumes for many months. I've been planning to switch to it for nearly 2 years. The change was delayed several times (and more Mini54s purchased) while other things, like the audio library & board, took priority.

Also, one less bootloader chip for Paul to maintain?

So much this!

The reality is I've strongly resisted adding features to the bootloader because the Mini54 is such a nightmare. Especially switching between clock speeds and power modes involves working around terrible bugs in the Mini54 silicon. Nuvoton's broken-English documentation leaves a lot to be desired, as does their reluctance to give honest answers to any questions about the shortcoming of their products. Some things about the Mini54 I even had to discover by reverse engineering.

Freescale's terse reference manuals won't win any writing awards, but they are complete and accurate and written in proper English. Freescale documents their errata. Freescale is also simply much, much better at designing processors and microcontrollers. Those little design decisions don't show up on a high-level comparison of tech specs and features, and most of things you'd take for granted and never appreciate... until you suffer using a not-as-well-designed part.

Presumably, one bootloader chip to rule them all... as the MKL02 can be programmed to support all Teensy MCUs (3.2, LC, and the upcoming 3++).

Yes, the new chip will allow supporting all board from a single chip with a single unified firmware.

The KL02 also will (hopefully) allow me to work on some really awesome new bootloader features in 2016 and beyond. Some of these are things I wanted to do all the way back before the initial release of Teensy 3.0 in September 2012.

The MKL02 is smaller than the 4x4mm version of the MiniTAN54, allows the retrofit of the external voltage regulator on the Teensy 3.x series boards.

Yes, the reduction from 16 to 9 square mm helped a lot. So did the change from 0.4 to 0.5 mm pitch. That and other improvements in the manufacturing process offset the cost of the new voltage regulator.
 
Paul,

By adding LP38691 it would also mean the quiescent current will increase even when the Teensy goes to sleep which adds up like around 55 uA.
Is this correct?
 
Hi Paul,
Is the schematic correct? Can the VOUT33 pin also be used as an input to power the internal USB circuitry?
Teensy 3.2.PNG
Regards,
Paul
 
Is the schematic correct? Can the VOUT33 pin also be used as an input to power the internal USB circuitry?l

I'm not Paul, but I can confirm that yes, 3.3V at the Vout3.3 pin can be used as an input for 3.3V power and that powering it is essential to allow USB to function. I found this out the hard way when I bypassed the MK20 VR altogether (supplying 3.3V only to the VCC pins) and then having no means of communicating with the MK20 over USB.

If I remember the relevant section in the Freescale manual correctly, you can run the chip at a lower VCC voltage and still communicate via USB as long as 3.3V is supplied to the Vout3.3V pin (7). IIRC, it's one way the OEM allows designers in power-restricted applications to reduce power consumption. The MK20 uses less power at lower voltages, yet 3.3V is used for signalling over USB. Hence the allowance for two different voltage levels (VCC vs. VOUT). I'm not sure how lower voltages affect the ADC, etc. but presume they're primarily intended for sleep mode and similar applications.

So, if you want to put the MK20 on a further power diet, only power pin 7 when it's needed and to leave the USB circuits dormant when no USB cable is attached. I suppose the easiest way to do this is to have a small dedicated external voltage regulator attached to VUSB that does nothing but power pin 7 externally (plus a capacitor or two for stability, see the Freescale manual for details). Naturally, you wouldn't be able to use the internal MK20 voltage regulator under that scenario, so you'd end up with a minimum of 2 voltage regulators per board (one for USB, the other for the MK20).
 
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Yeah, believe me, I of all people really wanted to keep those bottom side pads in the same locations. I ended up having to build a whole new set of pogo pins, just because a few of those moved. But it was unavoidable to cram the extra voltage regulator and large capacitor into the very limited space!
 
I received mine today and it appears to work fine. Did a quick hook-up to an esp8266 but haven't tasked it much other than typing AT+RST but it was great seeing some output from that in the serial monitor. My soldering skills are not so good and the 3.2 has a few extra little dots (like between GND and RX1) but I managed not to short anything. Thanks Paul!

P1010077.jpg
 
Got mine today and loaded first sketch fine. Will TeensyDuino be modify IDE to note : Tools /Board /Teensy 3.1&3.2?
 
Just wondering if these'll be available at Oshpark? I always grab a couple Teensies when ordering prototypes.

Edit: just read in another thread that they are already shipping 3.2. Cool beans!
 
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Paul - thank you so much for exposing the USB data lines on larger pads.

May I ask what your intention is with those bottom square pads under the USB connector? With the addition of the data pads, do you have something in mind for this; perhaps this is the pattern for a particular connector?
 
The additional square pads under the usb socket is for a Capacitor needed for USB Host mode.

Thanks for the reminder; I had forgotten that little nugget of info.
I am still curious as to whether the addition of the USB data lines are placed to conform to any specific connector or whether it's literally just to make it much easier to solder hookup wires to.
 
Excellent! I have four on order and the datasheet open in another window. I think this'll be the first post fastled3.1 update!

EDIT: never mind on the library update, read the mcu as being a different model at first - easiest new platform port ever!
 
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Any idea of pricing on the new bootloader and when volume quantities will be ready?
Also, it would be nice to have a list of things to do/think about in a redesign from the mini54 to the new one..
Looks great Paul! Thanks.
 
Depends on which one you're using. The biggest MiniTAN54 needed more capacitors, the 5x5mm version is similar in needs to the MKL02 (1).

From a connection point of view, note the drop of the I2C lines (which aren't getting used in the Teensy 3.0 or 3.1 either).

The number of connections to the MCU does not change. I did end up using two jumper resistors to avoid creating vias on a 2-layer board. One is for power, the other carries the reset signal. See above.
 
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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.

FWIW, I tried to find that larger chip your're referring to, and I presume it's either as-yet unreleased or not a MKL02Z32 series chip? I'm happy to wait to update the Eagle library but would love to do so before the new chip is released.
 
MKL price and availablility

I currently use the smallest minitan and would go with the smallest MKL.. Im planning a board rev in the next couple of weeks for other reasons, so if supply is good and price is better, I might as well bump the MiniTan off my board...

Depends on which one you're using. The biggest MiniTAN54 needed more capacitors, the 5x5mm version is similar in needs to the MKL02 (1).
 
Work is continuing here. My hope is we'll have these chips for sale in a couple weeks. Pricing will be similar but slightly less than the Mini54.

The 3mm size uses 0.5 mm pitch pins. Our assembly vendor that solders the Teensy boards reports it's much better for manufacturing. If you can wait a few weeks, I hight recommend holding out for the new chip!

The replacement ZIF socket (for the one that was damaged a couple weeks ago) *still* hasn't arrived. Frustrating! It should be here any day....

The larger chip is a Freescale MKL04 part. Full details will be published when the chips go on sale.

I'm also working on a reference board which you'll be able to order from OSH Park. It uses the larger chip and 603 and larger parts (no tiny 402s) for easier hand assembly.

FWIW, no Teensy has ever used ezport mode, not even the original Teensy 3.0 released via Kickstarter three years ago.
 
Work is continuing here. My hope is we'll have these chips for sale in a couple weeks. Pricing will be similar but slightly less than the Mini54.

The 3mm size uses 0.5 mm pitch pins. Our assembly vendor that solders the Teensy boards reports it's much better for manufacturing. If you can wait a few weeks, I hight recommend holding out for the new chip!

The replacement ZIF socket (for the one that was damaged a couple weeks ago) *still* hasn't arrived. Frustrating! It should be here any day....

The larger chip is a Freescale MKL04 part. Full details will be published when the chips go on sale.

I'm also working on a reference board which you'll be able to order from OSH Park. It uses the larger chip and 603 and larger parts (no tiny 402s) for easier hand assembly.

FWIW, no Teensy has ever used ezport mode, not even the original Teensy 3.0 released via Kickstarter three years ago.

Hi, got 4 of the teensy 3.2. has a friendlier feel to it. Think it may have something to do with the button.

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.
 
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