“Teensy” is a tiny size board compatible with Arduino software and libraries. Teensy 3.1 & 3.2 was the last version from Paul Stoffregen (PJRC Company) the creator of Teensy.
Paul started a Kickstarter campaign for The new Teensy 3.5 and 3.6 and until the time of preparation of this post, there are 1,697 backers and campaign raised $102,974 of the $5,000 goal with 15 days to go.
Teensy 3.5 and Teensy 3.6 have slightly differences. I made a full comparison in the bellow table:
Teensy 3.5 has a lower in features MCU (RAM, Flash, clock and some peripherals) which make it slightly cheaper than Teensy 3.6. Teensy 3.5 has 5v tolerance on all digital I/O pins.
Only Teensy 3.6 has a USB High Speed (480 Mbit/sec) port accessed using 5 pins on the board.
Teensy 3.5 and Teensy 3.6 are 6-layer PCB with 28 pins compatible with previous Teensy3.x models.
As we said, Teensy is compatible with Arduino software so Arduino IDE is the primary method used to program Teensy 3.6 and Teensy 3.5.
Paul (PJRC company) offered Teensy 3.5 for 23$ and Teensy 3.6 for 28$ for the Kickstarter campaign backers shipped in October.