ATSAMD21G18A-AU - 48MHz ARM Cortex-M0+ MCU | Microchip
MPN: ATSAMD21G18A-AU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.45 | $3.45 |
| 10 | $3.1 | $31.00 |
| 100 | $2.76 | $276.00 |
| 500 | $2.42 | $1,210.00 |
| 1,000 | $2.08 | $2,080.00 |
Drop-in alternatives for ATSAMD21G18A-AU β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAMD21G18A-AUT
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD21G18A-MU
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD21G18A-MUT
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD21G18A-AF
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD21G18A-AFT
β Drop-Inπ Reference alternative (not in catalog)
STM32F030C8T6
β Drop-Inβ In Stock
$1.55 / Unit
View Datasheet βATSAMD21G18A-AU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M0+ |
| Core Size | 32-Bit |
| Speed | 48 MHz |
| Program Memory Size | 256 KB (256K x 8) |
| Program Memory Type | FLASH |
| RAM Size | 32 KB |
| Number of I/O | 38 |
| Connectivity | I2C, SPI, UART/USART |
| Peripherals | DMA, I2S, POR, PWM, WDT |
| Number of Timers/Counters | 5 x 16-bit |
| ADC | 12-bit, 20-channel |
| DAC | 1 x 10-bit |
| Operating Voltage | 1.62V to 3.63V |
| Operating Temperature | -40C to +85C |
| Package | 48-TQFP (7x7 mm) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
ATSAMD21G18A-AU Pin Configuration
| Pin 1 | PA00 β General purpose I/O, can be used as ADC input |
| Pin 2 | PA01 β General purpose I/O, can be used as ADC input |
| Pin 3 | PA02 β General purpose I/O, can be used as ADC input |
| Pin 4 | PA03 β General purpose I/O, can be used as ADC input |
| Pin 5 | PA04 β General purpose I/O, can be used as ADC input |
| Pin 6 | PA05 β General purpose I/O, can be used as ADC input |
| Pin 7 | PA06 β General purpose I/O, can be used as ADC input |
| Pin 8 | PA07 β General purpose I/O, can be used as ADC input |
| Pin 9 | PA08 β General purpose I/O, can be used as ADC input |
| Pin 10 | PA09 β General purpose I/O, can be used as ADC input |
| Pin 11 | PA10 β General purpose I/O, can be used as ADC input |
| Pin 12 | PA11 β General purpose I/O, can be used as ADC input |
| Pin 13 | VDDIN β Power supply input |
| Pin 14 | GND β Ground |
| Pin 15 | PA12 β General purpose I/O, can be used as ADC input |
| Pin 16 | PA13 β General purpose I/O, can be used as ADC input |
| Pin 17 | PA14 β General purpose I/O, can be used as ADC input |
| Pin 18 | PA15 β General purpose I/O, can be used as ADC input |
| Pin 19 | PA16 β General purpose I/O, can be used as ADC input |
| Pin 20 | PA17 β General purpose I/O, can be used as ADC input |
| Pin 21 | PA18 β General purpose I/O, can be used as ADC input |
| Pin 22 | PA19 β General purpose I/O, can be used as ADC input |
| Pin 23 | PA20 β General purpose I/O, can be used as ADC input |
| Pin 24 | PA21 β General purpose I/O, can be used as ADC input |
| Pin 25 | PA22 β General purpose I/O, can be used as ADC input |
| Pin 26 | PA23 β General purpose I/O, can be used as ADC input |
| Pin 27 | PA24 β General purpose I/O, can be used as ADC input |
| Pin 28 | PA25 β General purpose I/O, can be used as ADC input |
| Pin 29 | PA26 β General purpose I/O, can be used as ADC input |
| Pin 30 | PA27 β General purpose I/O, can be used as ADC input |
| Pin 31 | PA28 β General purpose I/O, can be used as ADC input |
| Pin 32 | PA29 β General purpose I/O, can be used as ADC input |
| Pin 33 | PA30 β General purpose I/O, can be used as ADC input |
| Pin 34 | PA31 β General purpose I/O, can be used as ADC input |
| Pin 35 | PB00 β General purpose I/O, can be used as ADC input |
| Pin 36 | PB01 β General purpose I/O, can be used as ADC input |
| Pin 37 | PB02 β General purpose I/O, can be used as ADC input |
| Pin 38 | PB03 β General purpose I/O, can be used as ADC input |
| Pin 39 | PB04 β General purpose I/O, can be used as ADC input |
| Pin 40 | PB05 β General purpose I/O, can be used as ADC input |
| Pin 41 | PB06 β General purpose I/O, can be used as ADC input |
| Pin 42 | PB07 β General purpose I/O, can be used as ADC input |
| Pin 43 | PB08 β General purpose I/O, can be used as ADC input |
| Pin 44 | PB09 β General purpose I/O, can be used as ADC input |
| Pin 45 | PB10 β General purpose I/O, can be used as ADC input |
| Pin 46 | PB11 β General purpose I/O, can be used as ADC input |
| Pin 47 | PB12 β General purpose I/O, can be used as ADC input |
| Pin 48 | PB13 β General purpose I/O, can be used as ADC input |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this digital IC. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
ATSAMD21G18A-AU is suitable for 6 applications: Home Automation, Consumer Electronics, Industrial Control, IoT Nodes, Metering, Wearables.
Home Automation
The ATSAMD21G18A-AU is ideal for home automation controllers due to its low power consumption, rich peripheral set, and capacitive touch support. It can manage lighting, HVAC, and security systems with its multiple SERCOM interfaces for communication with sensors and actuators. The 48 MHz Cortex-M0+ core provides sufficient processing power for real-time control, while the Event System allows peripherals to trigger actions without CPU intervention, reducing power and improving responsiveness. Its 256 KB flash and 32 KB SRAM accommodate complex firmware for smart home protocols like Zigbee or Z-Wave via external modules. The device's wide operating voltage range (1.62V to 3.63V) allows direct battery operation, and its sleep modes enable energy-efficient standby, making it perfect for always-on home automation hubs.
Recommended
Consumer Electronics
In consumer electronics, the ATSAMD21G18A-AU excels in devices like smart watches, fitness trackers, and remote controls. Its low-power modes extend battery life, while the capacitive touch controller enables sleek, button-less interfaces. The 12-bit ADC can read analog sensors for environmental monitoring, and the DAC can generate audio tones or control analog circuits. The device's small 48-TQFP package fits compact PCBs, and its 5V tolerant I/O simplifies interfacing with legacy components. The Event System allows peripherals to wake the CPU only when needed, reducing average power consumption. With 256 KB flash, developers can implement rich user interfaces and firmware updates over-the-air. The SAMD21's popularity in Arduino-compatible boards ensures a vast ecosystem of libraries and examples, accelerating development.
Recommended
Industrial Control
The ATSAMD21G18A-AU is well-suited for industrial control applications such as PLCs, motor controllers, and sensor interfaces. Its robust peripheral set includes multiple timers for PWM generation, a 12-bit ADC for precise analog measurements, and several SERCOM interfaces for fieldbus communication like RS-485 or CAN via external transceivers. The device operates over -40C to +85C, making it suitable for harsh environments. The DMA controller offloads data transfer tasks from the CPU, ensuring deterministic response times. The Event System enables fast, low-latency inter-peripheral signaling, critical for real-time control loops. With 256 KB flash, complex control algorithms and safety routines can be stored. The device's 5V tolerant I/O allows direct connection to industrial sensors and actuators without level shifting, simplifying design and reducing BOM cost.
Recommended
IoT Nodes
For IoT nodes, the ATSAMD21G18A-AU offers an optimal balance of performance and power efficiency. Its low-power sleep modes, combined with the Event System, allow the device to operate for years on a single coin cell battery. The 12-bit ADC and multiple SERCOM interfaces enable connection to a wide range of sensors, from temperature and humidity to motion and gas. The device's 256 KB flash provides ample space for firmware that handles sensor data processing, communication protocols, and over-the-air updates. The SWD interface simplifies programming and debugging during development. The SAMD21's compatibility with Arduino and Mbed ecosystems accelerates prototyping, and its small package size fits into compact IoT modules. The device's wide voltage range supports direct battery connection, and its 5V tolerant I/O allows interfacing with 5V sensors without level shifters.
Recommended
Metering
The ATSAMD21G18A-AU is an excellent choice for smart metering applications, including electricity, water, and gas meters. Its low power consumption is critical for battery-operated meters that must last 10+ years. The 12-bit ADC with multiple channels can accurately measure voltage and current from sensors, while the Event System can trigger measurements at precise intervals without CPU involvement. The device's 256 KB flash can store metering data and calibration parameters, and the 32 KB SRAM handles real-time data processing. The multiple SERCOM interfaces allow communication with external modems or RF modules for remote data collection. The device's wide operating temperature range ensures reliable operation in outdoor environments. The SAMD21's robust peripheral set and low-power modes make it ideal for metering applications where accuracy and longevity are paramount.
Recommended
Wearables
The ATSAMD21G18A-AU is perfect for wearable devices like smartwatches, fitness bands, and medical monitors. Its ultra-low-power sleep modes, including standby with SleepWalking, allow the device to run for weeks on a small battery. The capacitive touch controller enables intuitive touch interfaces, and the 12-bit ADC can read biometric sensors like heart rate and skin conductance. The device's small 48-TQFP package fits into compact wearable PCBs, and its 5V tolerant I/O allows direct connection to various sensors. The Event System allows peripherals to wake the CPU only when necessary, minimizing power consumption. With 256 KB flash, developers can implement complex algorithms for activity tracking and health monitoring. The SAMD21's popularity in Arduino-compatible boards like the Arduino Zero makes it easy to prototype and develop wearable solutions.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD21G18A-AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD21G18A-AUT | ATSAMD21G18A-MU | STM32F030C8T6 |
|---|---|---|---|---|
| Package | 48-TQFP (7x7 mm) | 48-TQFP (7x7 mm) - same | 48-QFN (7x7 mm) - different | 48-LQFP (7x7 mm) - similar |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | STMicroelectronics |
| Core | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0 |
| Max Speed | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Flash Memory | 256 KB | 256 KB | 256 KB | 64 KB |
| SRAM | 32 KB | 32 KB | 32 KB | 8 KB |
| Number of I/O | 38 | 38 | 38 | 39 |
| Capacitive Touch | Yes | Yes | Yes | No |
Key Differentiators
- Capacitive touch support (vs STM32F030C8T6)
- Larger memory (vs STM32F030C8T6)
- Event System (vs STM32F030C8T6)
Design Notes
The ATSAMD21G18A-AU operates from 1.62V to 3.63V. Use a 100nF ceramic capacitor on each VDD pin and a 10uF bulk capacitor on the main supply. For low-power applications, utilize the standby sleep mode and configure the Event System to wake the device on peripheral events. Ensure the supply voltage is stable and within the recommended range to avoid brown-out resets.
Place decoupling capacitors as close as possible to the VDD pins. The 48-TQFP package has an exposed pad (EP) that should be soldered to a ground plane for thermal and electrical performance. Route the SWD interface (SWDIO, SWCLK) to a header for programming and debugging. Keep high-speed signals away from the crystal oscillator pins to avoid noise coupling.
Do not exceed the absolute maximum ratings: VDD max 3.8V, and I/O pins are 5V tolerant but do not apply more than 5.5V. Ensure the reset pin (RESET) is pulled up with a 10k resistor and a 100nF capacitor to ground for reliable reset. When using the ADC, configure the reference voltage correctly and add a filter capacitor on the reference pin to reduce noise.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified. Lead-free per datasheet.
