ATSAMD21J17A-MU

ATSAMD21J17A-MU is a Microchip SAM D21 microcontroller in a 32‑pin MU package. It’s a low‑power, 32‑bit MCU based on the ARM Cortex‑M0+ core, designed for USB‑enabled embedded apps.
Key features
- Core and speed: ARM Cortex‑M0+ up to 48 MHz; 1.62–3.63 V operation.
- Memory: 256 KB Flash, 32 KB SRAM; EEPROM emulation in flash.
- Peripherals: USB 2.0 Full‑Speed device, multiple SERCOMs (SPI/I2C/UART), 12‑bit ADC with several channels, timers, watchdog, event system, and power management features.
- Power: multiple sleep modes for low current in idle or standby.
- Package: 32‑pin MU (QFN) package suitable for compact designs.
- Programming/debug: SWD interface with tools like Microchip/Atmel Studio, MPLAB X, and third‑party IDEs; bootloader options available.
Typical use cases
- USB‑enabled sensors, small IoT devices, wearables, and Arduino‑style projects.
Development ecosystem
- Supported by Microchip Studio, Atmel START, MPLAB X, GCC ARM toolchains, with extensive example code and libraries.

Here are the main features of the ATSAMD21J17A-MU:
- 32-bit ARM Cortex‑M0+ core, up to 48 MHz
- On‑chip memory: up to 128 KB Flash and 16 KB SRAM
- Six SERCOM peripherals for UART/SPI/I2C
- 12‑bit ADC with multiple channels
- DMAC (Direct Memory Access) controller
- Peripheral Touch Controller (PTC) for capacitive touch
- Event System for cross‑peripheral routing and SleepWalking
- Timers/Counters and PWM outputs
- RTC with 32.768 kHz oscillator support
- EEPROM emulation in Flash; brown‑out detector and watchdog
- 28‑pin MU package (28‑pin QFN family), operating voltage ~1.65–3.6 V, industrial temperature range
- Flexible clock system (internal oscillators and DFLL) for power efficiency

- Pin count: 48 pins (MU package, 48‑pin MCU).
- Function: It is a SAM D21 family 32‑bit ARM Cortex‑M0+ microcontroller (ATSAMD21J17A) in the MU package, offering integrated flash and RAM plus peripherals (USB, SERCOM, ADC, timers, etc.) for embedded applications.

- Manufacturer: Microchip Technology Inc.
- What kind of company: A global semiconductor company that designs and manufactures embedded microcontrollers (PIC, AVR, SAM ARM Cortex-M), as well as analog and interface ICs. They acquired Atmel and are headquartered in the United States.

ATSAMD21J17A-MU is a low‑power 32‑bit ARM Cortex‑M0+ MCU with USB, SERCOMs, ADCs, timers, and flash/RAM. Its capabilities suit compact embedded designs. Typical application areas:
- USB-enabled devices (HID, CDC, custom USB peripherals)
- IoT and battery-powered sensing (environmental sensors, data loggers, asset trackers)
- Wearables and portable electronics
- Home/building automation (smart switches, thermostats, sensors)
- Small industrial instrumentation and control (panel meters, data acquisition)
- Education and prototyping (Arduino‑style boards, rapid development)

It comes in a 32-pin QFN (µQFN) package, 5×5 mm, typically with an exposed pad.