Some people have been asking why the Microchip ATSAMD51 was used for CircuitBrains Deluxe when there are newer chips out on the market. It’s a valid question that I want to address. A lot of weight in a product selection decision comes down to maturity, features, performance, cost, support, and availability. It’s not an easy decision to make when you are faced with hundreds of different microcontrollers available on the market. I feel that the ATSAMD51 is a pretty stable product, both in terms of lifecycle and installation base. It’s also chock full of features and I/O! The below bullet points summarize why the ATSAMD51 was a good choice for this project.

Mature Product & Widely Supported by Maker Community

• CircuitPython support
• Used in many Arduino boards

Lots of Microcontroller Horsepower

• ARM Cortex M4
• 120 MHz
• 192 KB SRAM

Native USB Device Support

• No need for extra hardware to support USB

Tons of I/O

• Total of 51 programmable I/O pins
• Has 2 DACs!
• 13 used in CircuitBrains Deluxe as Analog I/O
• 19 used in CircuitBrains Deluxe as Digital I/O
• Remaining pins allocated to SPI, I2C, USB, Flash Storage I/O, SWD

Six Serial Communication Interfaces (SERCOM)

• Many different communication protocols can be used simultaneously
• For example, CircuitBrains Deluxe has dedicated pins for both SPI and I2C

Small Package Size

• Comes in many footprints
• CircuitBrains Deluxe uses the 64-pin QFN that is 9mm x 9mm