ATSAMD21E15B-MFT - 48MHz ARM Cortex-M0+ MCU, 32KB Flash | Microchip
MPN: ATSAMD21E15B-MFT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.1 | $3.10 |
| 10 | $2.85 | $28.50 |
| 100 | $2.4 | $240.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.78 | $1,780.00 |
| 3,000 | $1.55 | $4,650.00 |
ATSAMD21E15B-MFT Overview
What is a microcontroller? A microcontroller (MCU) is a single-chip computer containing a processor core, program memory (Flash), data memory (SRAM), and programmable I/O peripherals. MCUs are the foundation of embedded systems, executing deterministic firmware for sensor reading, motor control, communication bridging, and user interface tasks. The SAM D21E family is positioned within Microchip's low-power ARM Cortex-M0+ portfolio, optimized for battery-powered IoT, consumer, and industrial sensing applications with sub-microamp sleep currents and a wide 1.62V-3.63V operating range.
Key features include 32KB in-system self-programmable Flash with signature row and user row, 4KB SRAM, a 12-channel 12-bit 350ksps ADC, six SERCOM modules (each configurable as UART/SPI/I2C), one USB 2.0 Full-Speed device/host with on-chip transceiver, and a 24-channel event system for CPU-independent peripheral-to-peripheral signaling. The device includes a 6-channel DMA controller, two I2S/SSC interfaces, RTC with calendar, and crypto/hash engines (AES, SHA, True Random Number Generator).
Architecturally, the SAM D21E implements the Cortex-M0+ v6-M profile with a Von Neumann bus to Flash and SRAM, single-cycle 32-bit ALU, and 4KB flash cache/branch cache that boosts effective throughput to 2.46 CoreMark/MHz. The integrated SleepWalking peripheral logic allows communication interfaces and timers to wake selected logic without waking the CPU. This event-driven architecture achieves measurable energy savings versus poll-based designs in always-on duty-cycled applications.
Typical applications include wearables and fitness bands, low-power wireless sensor nodes (BLE, LoRa, sub-GHz), USB HID peripherals, smart home sensor hubs, industrial control panels, and battery-operated data loggers requiring sub-1uA sleep states and rapid wake-to-active transitions. The AEC-Q100 qualification makes the automotive-grade revision suitable for dashboard clusters and body controllers.
When designing with this device, ensure proper decoupling with a 100nF ceramic capacitor close to each VDD pin and a 4.7uF bulk capacitor near the regulator output. Configure unused pins as inputs with enabled pull-ups to avoid floating leakage; unused pins configured as outputs risk injecting noise into analog rails.
Drop-in alternatives for ATSAMD21E15B-MFT — 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 ATSAMD21E15B-MFT (same form factor and footprint) — differing in ADC, Package, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAMD21E15B-AU
✅ Drop-In✓ In Stock
$1.45 / Unit
View Datasheet →ATSAMD21E15B-AFT
✅ Drop-In✓ In Stock
$1.96 / Unit
View Datasheet →ATSAMD21E17B-MFT
✅ Drop-In📋 Reference alternative (not in catalog)
ATSAMD21E18B-MFT
✅ Drop-In📋 Reference alternative (not in catalog)
ATSAMD21E16B-MFT
✅ Drop-In📋 Reference alternative (not in catalog)
ATSAMD21E15B-MFT Maximum Ratings & Electrical Characteristics
| Core Architecture | ARM Cortex-M0+ (32-bit) |
| Maximum CPU Frequency | 48 MHz |
| CoreMark Performance | 2.46 CoreMark/MHz |
| Flash Memory | 32 KB |
| SRAM | 4 KB |
| Package | 32-pin VQFN (5x5 mm) |
| Pin Count | 32 |
| Operating Voltage Range | 1.62 V to 3.63 V |
| Typical Operating Voltage | 3.3 V |
| Operating Temperature Range | -40 C to +125 C |
| SERCOM Modules | 6 (configurable as UART/SPI/I2C) |
| ADC | 12-bit, up to 350 ksps |
| USB | USB 2.0 Full-Speed Device/Host, integrated transceiver |
| DMA Channels | 6 |
| Event System Channels | 24 |
| Cryptographic Accelerators | AES, SHA, TRNG (SAM D21E variant set) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
ATSAMD21E15B-MFT Pin Configuration
| Pin 1 | PA00 — General-purpose I/O / SERCOM1 PAD0 / TCC2 WO0 |
| Pin 2 | PA01 — General-purpose I/O / SERCOM1 PAD1 / TCC2 WO1 |
| Pin 3 | PA02 — General-purpose I/O / ADC AIN0 / DAC VOUT |
| Pin 4 | PA03 — General-purpose I/O / ADC AIN1 / REF VREFA |
| Pin 5 | GND — Ground |
| Pin 6 | PA04 — General-purpose I/O / SERCOM0 PAD0 / TCC0 WO0 |
| Pin 7 | PA05 — General-purpose I/O / SERCOM0 PAD1 / TCC0 WO1 |
| Pin 8 | PA06 — General-purpose I/O / SERCOM0 PAD2 / ADC AIN6 |
| Pin 9 | PA07 — General-purpose I/O / SERCOM0 PAD3 / ADC AIN7 |
| Pin 10 | VDD — Digital supply voltage 1.62V-3.63V |
| Pin 11 | GND — Ground |
| Pin 12 | PA08 — General-purpose I/O / SERCOM2 PAD0 / TCC1 WO0 |
| Pin 13 | PA09 — General-purpose I/O / SERCOM2 PAD1 / TCC1 WO1 |
| Pin 14 | PA10 — General-purpose I/O / SERCOM2 PAD2 / TCC0 WO2 |
| Pin 15 | PA11 — General-purpose I/O / SERCOM2 PAD3 / TCC0 WO3 |
| Pin 16 | PA12 — General-purpose I/O / SERCOM4 PAD0 |
| Pin 17 | PA13 — General-purpose I/O / SERCOM4 PAD1 |
| Pin 18 | PA14 — General-purpose I/O / SERCOM4 PAD2 |
| Pin 19 | PA15 — General-purpose I/O / SERCOM4 PAD3 |
| Pin 20 | PA16 — General-purpose I/O / SERCOM3 PAD0 / TCC2 WO0 |
| Pin 21 | PA17 — General-purpose I/O / SERCOM3 PAD1 / TCC2 WO1 |
| Pin 22 | PA18 — General-purpose I/O / SERCOM3 PAD2 / TCC2 WO2 |
| Pin 23 | PA19 — General-purpose I/O / SERCOM3 PAD3 / TCC2 WO3 |
| Pin 24 | PA20 — General-purpose I/O / SERCOM5 PAD2 |
| Pin 25 | PA21 — General-purpose I/O / SERCOM5 PAD3 |
| Pin 26 | PA22 — General-purpose I/O / SERCOM5 PAD0 / TCC1 WO2 |
| Pin 27 | PA23 — General-purpose I/O / SERCOM5 PAD1 / TCC1 WO3 |
| Pin 28 | PA24 — USB D- (negative data line) |
| Pin 29 | PA25 — USB D+ (positive data line) |
| Pin 30 | RESET — Reset input, active low |
| Pin 31 | VDDIO — Digital I/O supply voltage |
| Pin 32 | GND — Ground (thermal pad exposed underneath) |
Typical Applications
ATSAMD21E15B-MFT is suitable for 6 applications: Wearable Fitness Bands, USB HID Peripherals (Keyboard, Mouse, HID Game Controller), Low-Power IoT Sensor Hubs, Industrial Control Panels (HMI Operator Interface), Battery-Powered Data Loggers, Automotive Body Electronics (AEC-Q100 Variant).
Wearable Fitness Bands
The ATSAMD21E15B-MFT's Cortex-M0+ core at 48MHz (2.46 CoreMark/MHz) and 4KB SRAM fit the limited memory budget of wearable fitness-band firmware while leaving headroom for heart-rate, accelerometer, and Bluetooth-friend protocol stacks. The 1.62V-3.63V supply range allows direct operation from a single coin-cell, and SleepWalking event logic plus sub-microamp deep-sleep currents stretch battery life to multi-month windows between charges.
Recommended
USB HID Peripherals (Keyboard, Mouse, HID Game Controller)
Integrated USB 2.0 Full-Speed with on-chip transceiver eliminates the external PHY in HID peripherals, reducing BOM cost by approximately $0.30 per unit. The 32KB Flash holds USB class-driver stacks plus customization firmware for macro keys, while 4KB SRAM buffers HID reports without DMA contention. The 32-pin VQFN footprint routes D-/D+ to PA24/PA25 with the standard 22-ohm series resistors for direct USB-B micro connectors.
Recommended
Low-Power IoT Sensor Hubs
Twenty-four channel event-system allows the ATSAMD21E15B-MFT to wake selectively on sensor activity without CPU intervention, while the 12-bit ADC at 350 ksps samples analog sensor outputs at intervals meeting most environmental monitoring requirements. Battery life in always-on applications like smart-home motion sensors reaches 3-5 years on a single CR2032 cell, supported by the device's -40C to +125C operating temperature for outdoor installations.
Recommended
Industrial Control Panels (HMI Operator Interface)
The ATSAMD21E15B-MFT's six SERCOM modules act independently as UART, SPI, or I2C interfaces to drive displays, keypads, and fieldbus gateways from a single MCU. The 32-pin VQFN footprint with -40C to +125C operating range is rated for industrial cabinet enclosures where ambient temperatures reach 70C. AES, SHA, and TRNG hardware accelerators authenticate HMI commands in security-conscious manufacturing sites without offloading to external crypto ICs.
Recommended
Battery-Powered Data Loggers
The 4KB SRAM plus 32KB Flash combined with the SleepWalking DMA allow unattended data logging at sample rates up to 350 ksps while consuming less than 1mA active. AES in-counter-mode encryption protects stored logs against physical tampering, and the TRNG seeds session keys for transport over optional LoRa or sub-GHz radio modules. The 32-pin QFN's thermal pad keeps junction temperature below 105C at full 48MHz CPU load in 70C ambient.
Recommended
Automotive Body Electronics (AEC-Q100 Variant)
The automotive-grade ATSAMD21E15B-MFT (suffix 'A') variant satisfies AEC-Q100 Grade 2 (-40C to +105C) with Functional Safety documentation, suiting body controllers for door modules, seat controllers, and HVAC dampers. The 12-bit ADC multiplexes thermistor readings for climate control, while the 24-channel event system wakes on LIN-bus activity without CPU wakeup. The 32-pin QFN compact footprint fits behind dashboard bezels with limited board space.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD21E15B-MFT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD21E15B-AU | ATSAMD21E15B-AFT | ATSAMD21E17B-MFT | ATSAMD21E18B-MFT | ATSAMD21E16B-MFT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | VQFN-32 (5x5 mm) | VQFN-32 (5x5 mm) - same | VQFN-32 (5x5 mm) - same | VQFN-32 (5x5 mm) - same | VQFN-32 (5x5 mm) - same | VQFN-32 (5x5 mm) - same |
| Flash Memory | 32 KB | 32 KB | 32 KB | 128 KB | 256 KB | 64 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 8 KB | 32 KB | 8 KB |
| Maximum CPU Frequency | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Operating Temperature Range | -40 C to +125 C (industrial) | -40 C to +125 C (industrial) | -40 C to +85 C (commercial) | -40 C to +125 C (industrial) | -40 C to +125 C (industrial) | -40 C to +125 C (industrial) |
| USB Controller | Yes (USB 2.0 Full-Speed) | Yes (USB 2.0 Full-Speed) | Yes (USB 2.0 Full-Speed) | Yes (USB 2.0 Full-Speed) | Yes (USB 2.0 Full-Speed) | Yes (USB 2.0 Full-Speed) |
| ADC Resolution | 12-bit | 12-bit | 12-bit | 12-bit | 12-bit | 12-bit |
| SERCOM Modules | 6 | 6 | 6 | 6 | 6 | 6 |
| Unit Price (qty 1, USD) | 3.10 | 3.00 | 3.00 | 4.00 | 5.20 | 3.40 |
Key Differentiators
- Lowest-memory SAM D21E variant for cost-optimized designs (vs ATSAMD21E18B-MFT (256KB Flash, 32KB SRAM))
- Integrated USB 2.0 Full-Speed with on-chip transceiver (vs External USB controller (e.g., MCP2210 SPI-to-USB bridge))
- Six independently-configurable SERCOM peripheral modules (vs NXP Kinetis KE04 (typically 3 UART modules))
- Wide industrial temperature grade (-40C to +125C) standard (vs Commercial-grade ATSAMD21E15B-AFT (-40C to +85C))
Design Notes
Provide a 100nF ceramic decoupling capacitor within 5mm of every VDD pin and a single 4.7uF X7R bulk capacitor near the regulator output. Estimated: at 48MHz active current draw of 4.5 mA from a 3.3V rail, instantaneous switching transients on VDD can reach 50mV; the 100nF cap supplies 200ns holdup that absorbs core inrush during clock-gated wake events.
Configure unused pins as inputs with internal pull-ups enabled rather than leaving them floating. Floating pins draw leakage of 1-5uA per pin, which would consume 64uA on 16 unused pins and dominate the deep-sleep current budget. Configure unused USB pins PA24/PA25 as GPIO inputs with pull-downs if USB is not used, and disable the 96MHz PLL on boot-up to reduce typical operating current by 0.6mA.
Solder the exposed thermal pad (GND) to a 50x50 mm (or larger) copper flood on the top layer with a 4-thermal-via array to the ground plane. Estimated: at 4.5 mA active current and 3.3V supply the total active power is approximately 15 mW, well within QFN-32 thermal limits. Industrial-grade parts at 85C ambient with the CPU at full 48MHz load keep junction below 95C under proper PCB layout.
Route USB D- (PA24) and D+ (PA25) as a 90-ohm differential pair with length matching within 150 mils to avoid signal-integrity issues at 12Mbps Full-Speed. Place the 22-ohm series resistors within 5mm of the MCU side and add ESD protection (e.g., USBLC6-2SC6) within 10mm of the USB connector. Keep the analog AVSS ground isolated from digital GND and join them at a single point near the MCU to minimize ADC noise.
Compliance Information
RoHS and REACH compliant per Microchip product page. MFT suffix denotes industrial temperature -40C to +125C, not AEC-Q100; choose ATSAMD21E15B-AUT for automotive-grade qualification. Halogen-free per JEDEC JS709B.
