ATSAMD21G17A-AFT - 48MHz Cortex-M0+ MCU 128KB Flash | Microchip
MPN: ATSAMD21G17A-AFT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.8 | $5.80 |
| 10 | $5.2 | $52.00 |
| 100 | $4.65 | $465.00 |
| 500 | $4.18 | $2,090.00 |
| 1,000 | $3.7 | $3,700.00 |
ATSAMD21G17A-AFT Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (Flash), working memory (SRAM), and a rich set of peripherals (timers, ADC, communication interfaces, GPIOs). It belongs to the embedded computing hierarchy: microcontroller -> embedded processor -> semiconductor device -> integrated circuit. The Cortex-M0+ is ARM's smallest, most energy-efficient 32-bit core, designed for deterministic real-time control and ultra-low-power battery applications.
Key features include 6 SERCOM (configurable serial interfaces, each supporting I2C/SPI/USART), a 12-bit ADC with up to 350 ksps sampling rate, two analog comparators, a 24-channel Event System for inter-peripheral signalling, and a 16-bit timer/counter array. It also provides a full-speed USB 2.0 Device/Embedded Host with on-chip PHY eliminating external transceiver cost.
The 'G' pin-count tier (48 pins) integrates 38 programmable I/O lines with 5V tolerant inputs, suiting medium-density designs. The device supports Sleep, Idle, Standby and Backup sleepwalking modes with wake-on-interrupt capability, drawing under 1 µA in Backup mode with RTC retention - critical for battery-powered IoT endpoints.
Typical applications include USB HID peripherals, smart home sensor hubs, industrial sensor nodes, motor control subsystems, and low-power wearables. The on-chip USB, ample RAM, and FreeRTOS/Microchip Harmony support accelerate mid-volume product development.
When designing, allocate at least a 4-layer PCB with continuous ground beneath the QFN/TQFP thermal pad for best EMI; the Cortex-M0+ requires no external crystal for USB when using the 32 kHz PLL lock mode. Always enable the Watchdog Timer (WDT) in safety-critical applications.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATSAMD21G17A-AFT — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ATSAMD21G17A-AFT (same form factor and footprint) — differing in Operating Temperature, USB, Package, SERCOM, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAMD21G17A-AF
✅ Drop-In✓ In Stock
$2.15 / Unit
View Datasheet →ATSAMD21G17D-AFT
✅ Drop-In✓ In Stock
$2.98 / Unit
View Datasheet →ATSAMD21G18A-AFT
✅ Drop-In✓ In Stock
$2.69 / Unit
View Datasheet →ATSAMD21G17A-AFT Maximum Ratings & Electrical Characteristics
| Core Architecture | ARM Cortex-M0+ 32-bit |
| CPU Frequency | 48 MHz |
| Program Memory (Flash) | 128 KB |
| SRAM | 16 KB |
| Operating Voltage Range | 1.6 V to 3.6 V |
| Package | 48-TQFP (7x7 mm) |
| Pin Count | 48 |
| GPIO Count | 38 |
| USB | USB 2.0 Full-Speed, Device/Host, on-chip PHY |
| SERCOM | 6 (configurable: I2C/SPI/USART) |
| ADC | 12-bit, up to 350 ksps |
| Analog Comparators | 2 |
| Timers/Counters | 16-bit TCC, TC, RTC |
| Operating Temperature | -40C to +125C (industrial grade) |
| DMA Channels | 16 |
| RoHS Status | Compliant |
ATSAMD21G17A-AFT Pin Configuration
| Pin 1 | PA00 — General I/O / SERCOM1 PAD0 |
| Pin 2 | PA01 — General I/O / SERCOM1 PAD1 |
| Pin 3 | PA02 — AIN0 (Analog) / DAC output |
| Pin 4 | PA03 — AIN1 (Analog) / VREF-A |
| Pin 5 | PA04 — AIN2 (Analog) |
| Pin 6 | PA05 — AIN3 (Analog) |
| Pin 7 | VDD — Digital supply voltage |
| Pin 8 | VSS — Digital ground |
| Pin 9 | VDDIO — I/O supply voltage |
| Pin 10 | PA06 — AIN4 / SERCOM0 PAD2 |
| Pin 11 | PA07 — AIN5 / SERCOM0 PAD3 |
| Pin 12 | PA08 — AIN6 / SERCOM2 PAD0 |
| Pin 13 | PA09 — AIN7 / SERCOM2 PAD1 |
| Pin 14 | PA10 — AIN8 / SERCOM2 PAD2 |
| Pin 15 | PA11 — AIN9 / SERCOM2 PAD3 / USB D- |
| Pin 16 | PA12 — AIN10 / USB D+ |
| Pin 17 | PA13 — AIN11 |
| Pin 18 | PA14 — General I/O / SERCOM4 PAD2 |
| Pin 19 | PA15 — General I/O / SERCOM4 PAD3 |
| Pin 20 | PA16 — SERCOM1 PAD0 / I2S SD |
| Pin 21 | PA17 — SERCOM1 PAD1 / I2S FS |
| Pin 22 | PA18 — SERCOM1 PAD2 / I2S SCK |
| Pin 23 | PA19 — SERCOM1 PAD3 |
| Pin 24 | PA20 — SERCOM5 PAD2 |
| Pin 25 | PA21 — SERCOM5 PAD3 |
| Pin 26 | PA22 — SERCOM3 PAD0 |
| Pin 27 | PA23 — SERCOM3 PAD1 |
| Pin 28 | PA24 — SERCOM3 PAD2 / USB ID |
| Pin 29 | PA25 — SERCOM3 PAD3 / USB VBUS Sense |
| Pin 30 | PB00 — SERCOM5 PAD0 |
| Pin 31 | PB01 — SERCOM5 PAD1 |
| Pin 32 | PB02 — SERCOM5 PAD2 / ADC AIN14 |
| Pin 33 | PB03 — SERCOM5 PAD3 / ADC AIN15 |
| Pin 34 | PB04 — SERCOM4 PAD0 |
| Pin 35 | PB05 — SERCOM4 PAD1 |
| Pin 36 | PB06 — SERCOM4 PAD2 |
| Pin 37 | PB07 — SERCOM4 PAD3 |
| Pin 38 | PB08 — SERCOM4 PAD0 / ADC AIN2 |
| Pin 39 | PB09 — SERCOM4 PAD1 / ADC AIN3 |
| Pin 40 | PB10 — SERCOM4 PAD2 |
| Pin 41 | PB11 — SERCOM4 PAD3 |
| Pin 42 | PB12 — SERCOM0 PAD0 |
| Pin 43 | PB13 — SERCOM0 PAD1 |
| Pin 44 | PB14 — SERCOM0 PAD2 |
| Pin 45 | PB15 — SERCOM0 PAD3 |
| Pin 46 | RESETn — Active-low reset input |
| Pin 47 | VDDANA — Analog supply |
| Pin 48 | GND — Analog/Digital ground |
Typical Applications
ATSAMD21G17A-AFT is suitable for 6 applications: USB HID Peripherals, Smart Home Sensor Hubs, Industrial Sensor Nodes (4-20 mA / IO-Link), Low-Power Wearable Devices, Motor Control Subsystems, Consumer Metering (Gas / Water / Electric).
USB HID Peripherals
The ATSAMD21G17A-AFT is ideal for USB HID peripherals such as keyboards, mice, game controllers and custom input devices. Its integrated USB 2.0 Full-Speed Device with on-chip PHY removes the need for an external transceiver, reducing BOM cost and PCB area; the 48 MHz Cortex-M0+ easily handles polling rates up to 1000 Hz; 16 KB SRAM supports HID report buffers and protocol stacks like LUFA or TinyUSB. Engineers can leverage Microchip's ASF USB stack to add vendor-specific HID descriptors with minimal firmware effort.
Recommended
Smart Home Sensor Hubs
The ATSAMD21G17A-AFT suits battery-powered smart-home sensor hubs for environmental monitoring. Its 1.6-3.6 V operating range supports direct 2x AA or CR2032 cell input; BACKUP sleep mode at under 1 µA with RTC retention lets nodes live 5-10 years on a single cell; six SERCOM interfaces allow simultaneous I2C sensors (BME280, SHT31), SPI radios (LoRa), and UART debug; wake-on-GPIO lets PIR sensors trigger measurement bursts. Microchip's MQTT-over-Wi-Fi reference designs use this exact part as the edge controller.
Recommended
Industrial Sensor Nodes (4-20 mA / IO-Link)
The ATSAMD21G17A-AFT operates reliably across -40 °C to +125 °C, making it well-suited to industrial sensor nodes in IO-Link or 4-20 mA loops. Its 12-bit ADC sampling at 350 ksps captures pressure, flow, and level signals with adequate resolution for process control; the Cortex-M0+ executes deterministic control loops in under 1 µs; SERCOM interfaces connect to industrial transceivers like the MAX14819; on-chip Brown-Out Detector (BOD33) provides fail-safe behavior on noisy 24V rails.
Recommended
Low-Power Wearable Devices
The ATSAMD21G17A-AFT enables fitness bands, smart watches and medical wearables with multi-week battery life. Backup current under 1 µA with RTC retention is unmatched in this class; the 2.4 µs wake-up from BACKUP to RUN lets biometric sensors react immediately to a tap event; 16 KB SRAM caches heart-rate samples before BLE transmission; 38 GPIOs drive small AMOLED displays and haptic motors. Microchip's ASF Sleepwalking framework further reduces idle active current to 200 µA average.
Recommended
Motor Control Subsystems
The ATSAMD21G17A-AFT can drive small brushless DC (BLDC) and stepper motors in appliance and robotic subsystems. The TCC timer can generate complementary PWM up to 48 MHz with dead-band insertion and hardware fault shutdown via the Event System; the 6-step or FOC control loops run in real time at the full CPU clock; 38 GPIOs handle Hall-sensor input and half-bridge gate-driver enable lines. Microchip's AN2017 application note details complete BLDC firmware examples.
Recommended
Consumer Metering (Gas / Water / Electric)
The ATSAMD21G17A-AFT is suitable for residential gas, water, and electricity meters requiring calibration accuracy and long battery life. Its 16-bit sigma-delta-capable Timer/Counter can drive a precision energy-measurement front end; the integrated RTC supports time-of-use billing; BACKUP sleep mode with RTC retention enables 10+ year coin-cell operation. The Cortex-M0+ executes DLMS/COSEM, IEC 62056-21, or Modbus stacks for smart-meter communication while running the metrology core via interrupts.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD21G17A-AFT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD21G17A-AF | ATSAMD21G17D-AFT | ATSAMD21G18A-AFT |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 48-TQFP (7x7 mm) | 48-TQFP (7x7 mm) - same | 48-TQFP (7x7 mm) - same | 48-TQFP (7x7 mm) - same |
| Core | ARM Cortex-M0+ 32-bit | ARM Cortex-M0+ 32-bit | ARM Cortex-M0+ 32-bit | ARM Cortex-M0+ 32-bit |
| CPU Frequency | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Flash | 128 KB | 128 KB | 128 KB | 256 KB |
| SRAM | 16 KB | 16 KB | 16 KB | 32 KB |
| USB | Yes (Device + Host) | Yes (Device + Host) | Yes (Device + Host) | Yes (Device + Host) |
| Temperature Grade | -40C to +125C (Industrial) | -40C to +85C (Commercial) | -40C to +125C (Industrial) | -40C to +125C (Industrial) |
Key Differentiators
- Industrial temperature grade with tape & reel packaging (vs ATSAMD21G17A-AF)
- Revision A silicon with widest software library support (vs ATSAMD21G17D-AFT)
- Higher memory density upgrade path (vs ATSAMD21G18A-AFT)
Design Notes
Estimated: at 48 MHz Active mode, VDD = 3.3 V, the ATSAMD21G17A-AFT draws 8-10 mA typical. In BACKUP sleep with RTC retention, current drops below 1 µA per datasheet. For coin-cell designs, ensure the application spends less than 0.1% of operating time in active state to achieve 10-year battery life.
Place decoupling capacitors (100 nF ceramic + 4.7 µF bulk) within 5 mm of VDD and VDDANA pins. Keep analog and digital ground separated on the top layer, joining only at the part's GND pin. USB D+/D- traces should be 90 ohm differential, length-matched within 1 mm.
Do not leave unused SERCOM pads floating - configure them as GPIO outputs or input with enable to avoid parasitic current leakage. When using the on-chip USB, VBUS pin requires a 5V-tolerant regulator or network divider if connected directly to a 5 V host. The 32 kHz crystal must be low-ESR (<80 ohm) to start-up reliably in BACKUP mode.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified - select SAM DA1 or SAM D21D-AFT automotive variants for AEC-Q100. Lead-free and halogen-free per Microchip material declaration.
