ATSAMD21E17A-MF - 48MHz Cortex-M0+ MCU 128KB Flash | Microchip
MPN: ATSAMD21E17A-MF ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.13 | $5.13 |
| 10 | $4.72 | $47.20 |
| 100 | $4.21 | $421.00 |
| 500 | $3.85 | $1,925.00 |
| 1,000 | $3.49 | $3,490.00 |
ATSAMD21E17A-MF Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory (Flash), working memory (SRAM), and a rich set of peripherals. The Cortex-M0+ is the smallest and most cost-optimized member of the ARM Cortex-M family, designed for deterministic embedded control with a Thumb-2 instruction set, low interrupt latency, and ultra-low sleep current. The ATSAMD21E17A-MF sits inside the broader hierarchy: MCU -> Cortex-M0+ microcontroller -> SAM D21 family -> 32-pin VQFN package. Its peripheral set (SERCOM, ADC, DAC, USB, timers) makes it a versatile system-on-chip for connected and sensor-driven products.
Key features include a full-speed USB 2.0 device interface with internal PHY, six SERCOM serial communication channels that can each be configured as UART, SPI, or I2C, a 12-bit 1 MSPS analog-to-digital converter with up to 20 channels, a 10-bit 350 kSPS digital-to-analog converter, two analog comparators, a 24-bit timer/counter for control applications, and an Event System for hardware-triggered peripheral interaction without CPU intervention. An on-chip 32 kHz RTC oscillator and a fractional digital phase-locked loop (FDPLL) provide flexible clocking, while 6 KB of user-accessible signature area supports secure boot and identity.
The device employs a single-cycle hardware multiplier, a nested vectored interrupt controller (NVIC), and Microchip's Sleepwalking peripheral gating for sub-microamp sleep currents down to approximately 3 microamps in full retention and less than 1 microamp in deep-power-down. Its BOD, brown-out detector, and WDT safeguard code execution under fault conditions. The 1.62 V minimum VDD permits operation from a single Li-ion, two AA cells, or energy-harvested supplies, broadening its applicability across consumer and industrial products.
Typical applications include home automation nodes, smart metering, wearable sensor hubs, industrial control and Human-Machine Interface (HMI) panels, low-power wireless sensor networks, and USB peripherals such as HID input devices, CDC bridges, and audio class interfaces. Consumers control peripherals such as LEDs, displays, and sensors through SERCOM and PWM channels while the integrated USB enables seamless PC connectivity.
When designing with this MCU, allocate the 32 pins carefully across USB, SWD, SERCOM, ADC, and GPIO. Use the 32.768 kHz crystal and load capacitors per datasheet reference design for RTC accuracy, and follow the SAM D21 hardware checklist to enable BOD33 and proper decoupling. The USB D-PUF lines need a 90 ohm common-mode choke and ESD protection.
This page synthesizes distributor pricing, drop-in same-package SAM D20/D21 alternatives, and practical design guidance beyond the manufacturer datasheet, helping engineers select the right variant and minimize risk.
Drop-in alternatives for ATSAMD21E17A-MF — 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 ATSAMD21E17A-MF (same form factor and footprint) — differing in ADC, Package, DAC, SRAM, USB.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAMD21E17A-MFT
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →ATSAMD21E18A-MF
✅ Drop-In✓ In Stock
$6.95 / Unit
View Datasheet →ATSAMD21E16A-MF
✅ Drop-In📋 Reference alternative (not in catalog)
ATSAMD21E16B-MU
✅ Drop-In✓ In Stock
$2.65 / Unit
View Datasheet →ATSAMD21E17A-MF Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology (formerly Atmel) |
| Series | SAM D21E |
| Core | ARM Cortex-M0+ 32-bit |
| Maximum Clock Frequency | 48 MHz |
| CoreMark/MHz | 2.46 |
| Flash Memory | 128 KB (128K x 8) |
| SRAM | 16 KB |
| RWW Flash Section | 4 KB |
| Supply Voltage (VDD) | 1.62 V to 3.63 V |
| Operating Temperature | -40C to +125C (industrial) |
| Package | 32-VQFN (5x5 mm) with exposed pad |
| Mounting Type | Surface Mount |
| USB Interface | USB 2.0 Full-Speed device with internal PHY |
| SERCOM Channels | 6 (each configurable as UART, SPI, or I2C) |
| ADC | 12-bit, up to 1 MSPS, up to 20 channels |
| DAC | 10-bit, 350 kSPS, 1 channel |
| Analog Comparators | 2 |
| Timers/Counters | 24-bit TCC, multiple 16-bit TC |
| GPIO | Up to 26 (package dependent) |
| RoHS Status | Compliant (Green) |
| MSL Level | MSL3 (per JEDEC J-STD-020) |
ATSAMD21E17A-MF Pin Configuration
| Pin 1 | PA00 — GPIO / SERCOM1[0] / TCC2[0] |
| Pin 2 | PA01 — GPIO / SERCOM1[1] / TCC2[1] |
| Pin 3 | PA02 — GPIO / SERCOM1[2] / Analog (AIN0) |
| Pin 4 | PA03 — GPIO / SERCOM1[3] / Reference (VREFA) |
| Pin 5 | PA04 — GPIO / SERCOM0[0] / TCC0[0] |
| Pin 6 | PA05 — GPIO / SERCOM0[1] / TCC0[1] |
| Pin 7 | PA06 — GPIO / SERCOM0[2] / Analog (AIN6) |
| Pin 8 | PA07 — GPIO / SERCOM0[3] / Analog (AIN7) |
| Pin 9 | VDD — Power supply input 1.62V-3.63V |
| Pin 10 | GND — Ground |
| Pin 11 | PA08 — GPIO / SERCOM2[0] / NMI |
| Pin 12 | PA09 — GPIO / SERCOM2[1] / Analog (AIN17) |
| Pin 13 | PA10 — GPIO / SERCOM2[2] / Analog (AIN18) |
| Pin 14 | PA11 — GPIO / SERCOM2[3] / Analog (AIN19) |
| Pin 15 | PA12 — GPIO / SERCOM4[0] / USB DP |
| Pin 16 | PA13 — GPIO / SERCOM4[1] / USB DM |
| Pin 17 | PA14 — GPIO / SERCOM4[2] / XCLK |
| Pin 18 | PA15 — GPIO / SERCOM4[3] / SERCOM3[3] |
| Pin 19 | PA16 — GPIO / SERCOM1[0] / TCC1[0] |
| Pin 20 | PA17 — GPIO / SERCOM1[1] / TCC1[1] |
| Pin 21 | PA18 — GPIO / SERCOM1[2] / SERCOM3[2] |
| Pin 22 | PA19 — GPIO / SERCOM1[3] / SERCOM3[3] |
| Pin 23 | PA20 — GPIO / SERCOM5[2] |
| Pin 24 | PA21 — GPIO / SERCOM5[3] |
| Pin 25 | PA22 — GPIO / SERCOM3[0] |
| Pin 26 | PA23 — GPIO / SERCOM3[1] |
| Pin 27 | PA24 — GPIO / SERCOM3[2] / USB SOF |
| Pin 28 | PA25 — GPIO / SERCOM3[3] / SERCOM5[3] |
| Pin 29 | PA27 — GPIO / SERCOM3[1] |
| Pin 30 | PA28 — GPIO / SERCOM5[0] / Reset |
| Pin 31 | PA30 — GPIO / SERCOM1[2] / SWDIO |
| Pin 32 | PA31 — GPIO / SERCOM1[3] / SWCLK |
| Pin 33 | EPAD — Exposed thermal pad - must be soldered to GND plane |
Typical Applications
ATSAMD21E17A-MF is suitable for 6 applications: Home Automation and Smart Sensor Nodes, USB HID and CDC Peripheral Devices, Smart Metering and Energy Measurement, Industrial HMI and Control Panels, Wearable Health and Fitness Devices, Low-Power Wireless IoT Endpoints.
Home Automation and Smart Sensor Nodes
The ATSAMD21E17A-MF's Cortex-M0+ core at 48 MHz, 128 KB Flash, 16 KB SRAM, and 6 SERCOM channels make it a strong fit for home automation hubs and wireless sensor nodes. The 1.62 V minimum VDD enables direct coin-cell or 2x AA operation without an external boost, while Sleepwalking peripherals and sub-3 uA full-retention sleep extend battery life. In a typical Zigbee/Thread/BLE co-processor design, the E17A runs the application MCU role, polling sensors over I2C/SPI SERCOM, driving LEDs via TCC PWM, and forwarding events to the radio. The 4 KB RWW Flash region supports OTA bootloader staging while the main app continues running, critical for in-field firmware updates. Engineers benefit from the wide 1.62-3.63 V range, 6 SERCOM flexibility, and Microchip's Atmel Start / MPLAB Harmony code generation for rapid prototyping.
Recommended
USB HID and CDC Peripheral Devices
The ATSAMD21E17A-MF integrates a USB 2.0 Full-Speed device with internal PHY, removing the need for an external transceiver and reducing BOM cost for HID peripherals. With 48 MHz Cortex-M0+ headroom and 2.46 CoreMark/MHz, it comfortably runs USB HID class stacks, CDC ACM bridges, and composite USB devices. A typical HID keyboard design maps a key matrix to GPIO interrupts, services the USB endpoint via the integrated SAMD21 USB stack, and enters Idle sleep between keystrokes to minimize current. CDC bridges benefit from the 6 SERCOM channels for UART-to-USB conversion. The 32-VQFN exposed pad simplifies layout on compact peripherals like mice, presentation clickers, and USB-to-UART adapters. ASF (Advanced Software Framework) and Microchip Harmony provide ready-to-use USB class drivers, drastically reducing firmware development time.
Recommended
Smart Metering and Energy Measurement
The ATSAMD21E17A-MF is well matched to single-phase smart meters, electricity/gas/water metering, and energy-monitoring IoT endpoints. Its 12-bit 1 MSPS ADC with up to 20 channels can simultaneously sample voltage and current waveforms for power-quality and harmonic analysis, while the 10-bit DAC drives analog front-end calibration. SERCOM channels connect to metrology AFE chips over SPI, to LCD or LED displays on I2C, and to wireless modules for backhaul. The 1.62 V minimum VDD supports battery-backed RTC operation across power outages, preserving billing timestamps. Hardware Event System allows direct ADC-to-timer triggers without CPU wake-up, dramatically reducing average current in battery-augmented metering. The 128 KB Flash accommodates complex metering stacks (DLMS/COSEM, IEC 62056) and signed firmware verification.
Recommended
Industrial HMI and Control Panels
Industrial Human-Machine Interface (HMI) panels and control boards benefit from the ATSAMD21E17A-MF's 48 MHz performance, 12-bit ADC, and rich PWM outputs for motor/valve/LED driving. The 128 KB Flash holds graphic libraries, touchscreen drivers, and Modbus RTU stacks; 16 KB SRAM supports small graphical framebuffers and protocol buffers. SERCOM channels handle RS-485 transceivers, I2C sensors, and SPI displays in parallel. The -40C to +125C industrial temperature rating permits deployment in factory cabinets and outdoor enclosures. The BOD33 brown-out detector and dual-window watchdog ensure safe operation in noisy industrial environments. The exposed thermal pad of the 32-VQFN package enables sustained full-CPU operation under elevated ambient temperatures typical of sealed enclosures.
Recommended
Wearable Health and Fitness Devices
The ATSAMD21E17A-MF is well suited to wearable health monitors, fitness bands, and medical sensor patches due to its 1.62 V minimum VDD (single coin-cell friendly), 3 uA full-retention sleep current, and Event System for autonomous sensor sampling. The 12-bit ADC reads bioelectrical signals (ECG, GSR, body temperature) while the 10-bit DAC generates bias voltages for analog front-ends. BLE/Wi-Fi companion chips communicate over SERCOM (UART/SPI). The compact 5x5 mm 32-VQFN enables ultra-thin wearable form factors. Hardware AES peripheral (when paired with SAMD21 crypto variant) supports encrypted health data at rest. Touch-support via PTC (Peripheral Touch Controller) enables capacitive button/wheel interfaces without dedicated touch ICs.
Recommended
Low-Power Wireless IoT Endpoints
The ATSAMD21E17A-MF serves as the application MCU in low-power wireless IoT endpoints that pair with external sub-GHz, Bluetooth Low Energy, or LoRa transceivers. Its Cortex-M0+ at 48 MHz executes lightweight wireless stacks (BLE host, LoRaWAN node, Matter-over-Thread) while the SERCOM channels maintain multiple SPI/UART links to transceivers. The 1.62 V minimum VDD enables direct battery operation without a boost converter; Sleepwalking peripherals and Event System minimize active time. The 4 KB RWW Flash allows OTA firmware staging while the main app continues running, a critical feature for long-life IoT deployments. Industrial -40C to +125C temperature range supports outdoor or factory deployments, and the exposed thermal pad helps dissipate heat during sustained transmit bursts.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD21E17A-MF — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD21E17A-MFT | ATSAMD21E18A-MF | ATSAMD21E16A-MF | ATSAMD21E17A-AU | ATSAMD21E16B-MU |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 32-VQFN (5x5) | 32-VQFN (5x5) - same | 32-VQFN (5x5) - same | 32-VQFN (5x5) - same | 32-TQFP (7x7) - DIFFERENT, PCB rework | 32-VQFN (5x5) - same |
| Flash | 128 KB | 128 KB - identical | 256 KB - double | 64 KB - half | 128 KB - identical | 64 KB - half |
| SRAM | 16 KB | 16 KB - identical | 32 KB - double | 8 KB - half | 16 KB - identical | 8 KB - half |
| Core / Max Clock | Cortex-M0+ / 48 MHz | Cortex-M0+ / 48 MHz | Cortex-M0+ / 48 MHz | Cortex-M0+ / 48 MHz | Cortex-M0+ / 48 MHz | Cortex-M0+ / 48 MHz |
| Supply Voltage | 1.62 V to 3.63 V | 1.62 V to 3.63 V | 1.62 V to 3.63 V | 1.62 V to 3.63 V | 1.62 V to 3.63 V | 1.62 V to 3.63 V |
| USB | USB 2.0 FS Device | USB 2.0 FS Device | USB 2.0 FS Device | USB 2.0 FS Device | USB 2.0 FS Device | USB 2.0 FS Device |
| Approx. Unit Price (qty 1) | $5.13 | $5.13 - identical | $6.20 - higher (more Flash) | $4.10 - lower (less Flash) | $5.20 - similar | $4.30 - similar |
Key Differentiators
- Doubled Flash and SRAM headroom with identical pinout (vs ATSAMD21E18A-MF)
- Cost-optimized with 50% memory reduction (vs ATSAMD21E16A-MF)
- Compact 5x5 mm VQFN with proper thermal pad (vs ATSAMD21E17A-AU (32-TQFP))
Design Notes
The ATSAMD21E17A-MF accepts 1.62 V to 3.63 V on VDD; place a 1 uF X7R decoupling capacitor within 5 mm of each VDD/GND pair and a 100 nF within 2 mm of the pin. The on-chip BOD33 should be enabled in fuses with a threshold of 1.6 V to prevent Flash corruption during brown-out events. For USB-powered applications, VBUS must be sensed through a resistive divider on a GPIO to detect host connection without back-powering the bus.
The 32-VQFN exposed thermal pad must be soldered to a contiguous ground copper pour of at least 25 mm^2 on the top layer, plus thermal vias to inner ground layers (0.3 mm pitch, 0.2 mm drill). Without the thermal pad properly soldered, theta_JA exceeds 90 C/W and the device will throttle or fail at industrial temperature extremes. For sustained USB transmissions at 48 MHz full CPU load, the resulting dissipation is approximately 40-50 mW which is well within the 5x5 mm VQFN thermal envelope when the pad is properly soldered.
Route the USB DP/DM pair as a 90 ohm differential with maximum length under 50 mm, avoiding stubs and keeping away from switching signals. The 32.768 kHz crystal must be placed within 5 mm of XIN/XOUT with a grounded guard ring to minimize noise pickup; load capacitors per crystal datasheet (typically 12-18 pF) sized to the crystal's load rating, NOT the MCU pin capacitance. SWDIO/SWCLK lines should be 50 ohm single-ended and route directly to a debug header without series resistors in production.
Common pitfalls: (1) Forgetting to enable SERCOM pad multiplexing in PORT->PMUX registers results in silent GPIO-only behavior even with correct peripheral setup; (2) Configuring the FDPLL without a valid 32.768 kHz source causes USB start-of-frame timing to drift and HID reports to fail enumeration; (3) Writing to NVMCTRL without first checking the AHB error flag can corrupt Flash during a power glitch; (4) Enabling the DAC output on a pin without disabling the analog input buffer causes ADC readings to saturate. Always consult Microchip Application Note AN-2466 (Migration from SAMD20) and the SAM D21 hardware checklist.
For mixed-signal designs using the 12-bit ADC, separate analog (AVDD) and digital (VDD) planes are recommended, with the AVS pin filtered by a ferrite bead and 1 uF + 100 nF decoupling. Route analog traces away from SERCOM switching signals. Use a guard trace around sensitive analog inputs (AIN0-AIN19), tying to analog ground. The DAC output should drive high-impedance loads only (>10 kohm) without buffering; a CMOS op-amp buffer (e.g. MCP6001) is recommended for low-impedance applications.
Compliance Information
Microchip SAM D21 family is RoHS and REACH compliant per product page; MSL3 per JEDEC J-STD-020. AEC-Q100 not qualified - for automotive applications, use ATSAMxA1 automotive variants.
