Teensy 3.5 without headers

The awesome new Teensy 3.5 is a small, breadboard-friendly development board designed by Paul Stoffregen and PJRC. Teensy 3.5 brings a low-cost 32-bit ARM Cortex-M4 platform to hobbyists, students and engineers, using an adapted version of the Arduino IDE (Teensyduino) or programming directly in C language. Teensy 3.5 is an upgrade over 3.2, for when you need even more power!

Version 3.5 features a 32 bit 120 MHz ARM Cortex-M4 processor with floating point unit. All digital pins are 5 volt tolerant. The unique specs for the 3.5 are:

• 120 MHz ARM Cortex-M4 with Floating Point Unit
• 512K Flash, 192K RAM, 4K EEPROM
• Microcontroller Chip MK64FX512VMD12 (PDF link)
• 1 CAN Bus Port
• 16 General Purpose DMA Channels
• 5 Volt Tolerance On All Digital I/O Pins

The latest in the line of very powerful, USB-capable microcontrollers, the Teensy 3.5 and 3.6 development boards are faster, more capable, and bigger, putting even more pins on a solderless breadboard. Teensy 3.5 offers a little bit less in its features (MCU, RAM, Flash, clock and some peripherals) which makes 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.

Please note: Teensy 3 boards are not official Arduino-brand products. Although the Teensyduino IDE has been adapted so that many Arduino projects will work with the Teensy, there will still be a lot of libraries and shields that may not work with this device! If you’re new to microcontrollers, we suggest going with a classic Arduino UNO since all Arduino projects, examples and libraries will work with it.

More Specifications, Details & Features:

• 62 I/O Pins (42 breadboard friendly)
• 25 Analog Inputs to 2 ADCs with 13 bits resolution
• 2 Analog Outputs (DACs) with 12 bit resolution
• 20 PWM Outputs (Teensy 3.6 has 22 PWM)
• USB Full Speed (12 Mbit/sec) Port
• Ethernet mac, capable of full 100 Mbit/sec speed
• Native (4 bit SDIO) micro SD card port
• I2S Audio Port, 4 Channel Digital Audio Input & Output
• 14 Hardware Timers
• Cryptographic Acceleration Unit
• Random Number Generator
• CRC Computation Unit
• 6 Serial Ports (2 with FIFO & Fast Baud Rates)
• 3 SPI Ports (1 with FIFO)
• 3 I2C Ports (Teensy 3.6 has a 4th I2C port)
• Real Time Clock

Product description is from Adafruit website.