ATSAMC21E16A-AUT - 48MHz Cortex-M0+ MCU 64KB Flash | Microchip
MPN: ATSAMC21E16A-AUT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.71 | $4.71 |
| 10 | $4.12 | $41.20 |
| 100 | $3.55 | $355.00 |
| 500 | $3.1 | $1,550.00 |
| 1,000 | $2.78 | $2,780.00 |
ATSAMC21E16A-AUT Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (Flash), working memory (SRAM), and peripherals on one die. Cortex-M0+ is an ARM processor core optimized for energy efficiency and deterministic interrupt response, widely used in cost-sensitive embedded designs. The SAM C21 family extends the Cortex-M0+ line to 5V I/O tolerance, making it easier to interface with industrial sensors, motor drivers, and 24V logic without level shifters.
Key differentiating features include a 5V-tolerant I/O structure (operating from 2.7V to 5.5V), a full-speed USB 2.0 device interface, a CAN-FD controller for automotive-grade networking, six SERCOM modules that can each be configured as UART, SPI, or I2C, and a 12-bit ADC with up to 10 channels. A single-cycle hardware multiplier, Micro Trace Buffer, and Memory Protection Unit (MPU) support real-time control and safety-oriented firmware development.
Architecturally, the device is built around the Cortex-M0+ core with a 2-stage pipeline, integrated Nested Vectored Interrupt Controller (NVIC), and Microchip's standard SAM D/C peripheral set. The 48 MHz operation delivers approximately 45 DMIPS while keeping active current low, and the on-chip voltage regulator supports both low-power Sleep, Standby, and Backup modes for battery-driven nodes. The functional safety (FuSa) variant labeling indicates documentation support for IEC 60730 class-B safety libraries.
Typical applications include CAN-FD-connected industrial sensor nodes, building automation controllers, low-end automotive body and HVAC modules, USB human-interface devices, small motor-control BLDC boards, and battery-backed metering. The 5V tolerance and integrated CAN-FD distinguish the C21 from the lower-voltage SAMD20/D21 family for harsh-environment designs.
When designing with this part, use the ASF4 / MCC peripheral libraries to configure SERCOM instances and validate your CAN-FD timing against the Bosch CAN-FD specification. Decouple VDDIO and VDDCORE with separate 100 nF capacitors placed within 3 mm of the pins, and route the XIN/XOUT traces symmetrically to minimize duty-cycle distortion.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives, and practical design notes not aggregated on a single manufacturer or distributor page.
Drop-in alternatives for ATSAMC21E16A-AUT — 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 ATSAMC21E16A-AUT (same form factor and footprint) — differing in Package, ADC, Operating Temperature, RoHS Status, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAMC21E17A-AUT
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.45 / Unit
View Datasheet →ATSAMC20E16A-AUT
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.96 / Unit
View Datasheet →ATSAMC21E18A-AUT
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$3.07 / Unit
View Datasheet →ATSAMC21E15A-AUT
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATSAMC20G16A-AUT
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.65 / Unit
View Datasheet →ATSAMC21E16A-AUT Maximum Ratings & Electrical Characteristics
| Core | ARM Cortex-M0+ (32-bit) |
| Maximum CPU Frequency | 48 MHz |
| Program Memory (Flash) | 64 KB |
| SRAM | 8 KB |
| Auxiliary Flash (EEPROM emulation) | 2 KB |
| Supply Voltage Range | 2.7 V to 5.5 V |
| I/O Tolerance | 5 V tolerant |
| Number of I/O Pins | 26 |
| Package | 32-pin TQFP (7x7 mm) |
| Operating Temperature | -40 C to +85 C (industrial) |
| ADC | 12-bit, up to 10 channels |
| Communication Peripherals | CAN-FD, USB 2.0 FS, 6x SERCOM (UART/SPI/I2C) |
| Timers | 16-bit TCC, TC, and RTC |
| Hardware Multiplier | Single-cycle (32-bit result) |
| Memory Protection Unit (MPU) | Yes |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant (per Microchip product page) |
ATSAMC21E16A-AUT Pin Configuration
| Pin 1 | PA03 — GPIO / ADC AIN1 |
| Pin 2 | PA04 — GPIO / ADC AIN2 / VREFB |
| Pin 3 | PA05 — GPIO / ADC AIN3 |
| Pin 4 | PA06 — GPIO / ADC AIN4 |
| Pin 5 | PA07 — GPIO / ADC AIN5 |
| Pin 6 | PA08 — GPIO / SERCOM0 PAD0 / I2S |
| Pin 7 | PA09 — GPIO / SERCOM0 PAD1 / I2S |
| Pin 8 | PA10 — GPIO / SERCOM0 PAD2 |
| Pin 9 | PA11 — GPIO / SERCOM0 PAD3 |
| Pin 10 | VDD — Digital supply voltage (2.7V to 5.5V) |
| Pin 11 | GND — Ground |
| Pin 12 | PA14 — GPIO / XIN |
| Pin 13 | PA15 — GPIO / XOUT |
| Pin 14 | PA16 — GPIO / SERCOM1 PAD0 / I2S |
| Pin 15 | PA17 — GPIO / SERCOM1 PAD1 / I2S |
| Pin 16 | PA18 — GPIO / SERCOM1 PAD2 |
| Pin 17 | PA19 — GPIO / SERCOM1 PAD3 |
| Pin 18 | PA20 — GPIO / SERCOM3 PAD0 |
| Pin 19 | PA21 — GPIO / SERCOM3 PAD1 |
| Pin 20 | PA22 — GPIO / SERCOM3 PAD2 |
| Pin 21 | PA23 — GPIO / SERCOM3 PAD3 / USB SOF |
| Pin 22 | PA24 — GPIO / USB D- |
| Pin 23 | PA25 — GPIO / USB D+ |
| Pin 24 | PA27 — GPIO |
| Pin 25 | PA28 — GPIO / CAN TX |
| Pin 26 | PA29 — GPIO / CAN RX / BOOT |
| Pin 27 | VDDIO — I/O supply voltage (tied to VDD in single-supply mode) |
| Pin 28 | GND — Ground |
| Pin 29 | PA30 — GPIO / SWCLK |
| Pin 30 | PA31 — GPIO / SWDIO |
| Pin 31 | NRST — Active-low reset input |
| Pin 32 | VDDCORE — Internal core voltage regulator output (decoupling only) |
Typical Applications
ATSAMC21E16A-AUT is suitable for 6 applications: CAN-FD Industrial Sensor Node, Building Automation Controller, USB Human Interface Device (HID), Small BLDC Motor Controller, Battery-Backed Metering / Smart Sensor, Low-End Automotive Body / HVAC Module.
CAN-FD Industrial Sensor Node
The ATSAMC21E16A-AUT's integrated CAN-FD controller and 5V-tolerant I/O make it a strong fit for industrial sensor nodes communicating over ISO 11898-1:2015 networks. With 64 KB Flash it accommodates the Bosch CAN-FD stack plus application code, and the 48 MHz Cortex-M0+ delivers deterministic 1 ms control loops typical of process-control loops. The 8 KB SRAM holds CAN message buffers and a small RTOS, while the 12-bit ADC reads analog sensors without an external front-end. Unlike lower-voltage SAM D21 parts, it interfaces directly with 5V industrial sensors and 24V level-shifted signals common in factory automation, reducing BOM cost. Designers typically pair it with a TLE7250-3 CAN transceiver for a complete node.
Recommended
Building Automation Controller
Building automation controllers need to drive relays, triacs, and 0-10V analog outputs while communicating on RS-485 or CAN backbones. The ATSAMC21E16A-AUT's 5V I/O tolerance interfaces directly with legacy building-automation peripherals, and its 6 SERCOM modules can be independently configured as UART, SPI, or I2C to handle multiple building-protocol transceivers. The 48 MHz core executes BACnet or Modbus stacks with margin, and the 64 KB Flash holds the application plus a small bootloader for OTA updates. The 32-pin TQFP is a compact footprint that fits standard DIN-rail module PCBs, and the -40 C to +85 C industrial temperature range handles unheated electrical closets.
Recommended
USB Human Interface Device (HID)
The ATSAMC21E16A-AUT's integrated USB 2.0 full-speed device controller with on-chip pull-up and internal 3.3V regulator enables compact USB HID designs without an external PHY. With 64 KB Flash it fits full HID report descriptors, vendor-specific feature reports, and a small USB stack such as the Microchip USB Framework. The 32-pin TQFP keeps the PCB compact for cable-mounted peripherals, and the 5V-tolerant I/O is convenient for driving status LEDs directly from VBUS through a current-limiting resistor. The 8 KB SRAM is sufficient for HID ring buffers and small vendor command processing, while the 48 MHz Cortex-M0+ handles polling at the USB 1 ms frame interval.
Recommended
Small BLDC Motor Controller
The ATSAMC21E16A-AUT drives small brushless DC motors in appliances, fans, and pumps where its 48 MHz Cortex-M0+ runs field-oriented control (FOC) loops at the required 10 kHz PWM rate. The 5V I/O tolerance interfaces directly with 5V gate drivers, eliminating level shifters, and the TCC timer can generate complementary 3-phase PWM with dead-band insertion. The 12-bit ADC samples phase currents and back-EMF synchronously to the PWM center, while the 8 KB SRAM holds FOC state variables and a small lookup table. The 32-pin TQFP fits low-profile motor-control PCBs and supports the industrial -40 C to +85 C operating range required by white goods.
Recommended
Battery-Backed Metering / Smart Sensor
The ATSAMC21E16A-AUT's low-power Backup mode at approximately 3 microamps with RTC running and full SRAM retention supports battery-backed metering and smart-sensor applications. The 32.768 kHz crystal input drives the RTC, and the Cortex-M0+ wakes to active mode on RTC alarm to take ADC readings, log them to the 2 KB EEPROM-emulation Flash, and return to sleep. With 64 KB Flash it accommodates segmented metering firmware plus a small bootloader, while the 8 KB SRAM holds intermediate samples and a small ring buffer. CAN-FD or UART can be used for last-mile communication back to a gateway.
Recommended
Low-End Automotive Body / HVAC Module
Automotive body controllers, HVAC flap drivers, and seat-control modules typically operate from a 12V bus stepped down to 5V and need CAN communication plus a moderate amount of GPIO. The ATSAMC21E16A-AUT's integrated CAN-FD controller, 5V I/O, and -40 C to +85 C industrial temperature make it a fit for cabin-mounted modules where the underhood AEC-Q100 Grade 0 requirement does not apply. The 48 MHz Cortex-M0+ runs the CAN-FD stack and a small control loop simultaneously, while the 64 KB Flash holds the application plus a CAN bootloader for service reflashing. The 32-pin TQFP is compact enough for distributed body modules mounted behind trim panels.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMC21E16A-AUT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMC21E17A-AUT | ATSAMC20E16A-AUT | ATSAMC21E18A-AUT | ATSAMC21E15A-AUT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 32-pin TQFP (7x7 mm) | 32-pin TQFP (7x7 mm) - same | 32-pin TQFP (7x7 mm) - same | 32-pin TQFP (7x7 mm) - same | 32-pin TQFP (7x7 mm) - same |
| Core | ARM Cortex-M0+ (48 MHz) | ARM Cortex-M0+ (48 MHz) | ARM Cortex-M0+ (48 MHz) | ARM Cortex-M0+ (48 MHz) | ARM Cortex-M0+ (48 MHz) |
| Flash | 64 KB | 72 KB (+12.5%) | 64 KB (same) | 256 KB (+300%) | 32 KB (-50%) |
| SRAM | 8 KB | 8 KB (same) | 8 KB (same) | 8 KB (same) | 4 KB (-50%) |
| CAN-FD | Yes | Yes | No (CAN 2.0B only) | Yes | Yes |
| USB 2.0 FS | Yes | Yes | Yes | Yes | Yes |
| I/O Count | 26 | 26 (same) | 26 (same) | 26 (same) | 26 (same) |
| Supply Voltage | 2.7V to 5.5V (5V tolerant I/O) | 2.7V to 5.5V (5V tolerant I/O) | 2.7V to 5.5V (5V tolerant I/O) | 2.7V to 5.5V (5V tolerant I/O) | 2.7V to 5.5V (5V tolerant I/O) |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
Key Differentiators
- Integrated CAN-FD controller with 5V I/O tolerance in 32-pin TQFP (vs ATSAMD21E16B-AUT)
- 64 KB Flash dual-bank with EEPROM emulation (vs ATSAMC21E15A-AUT)
- Mature MPLAB Harmony v3 and ASF4 software support (vs Generic Cortex-M0+ MCUs)
Design Notes
Estimated: The ATSAMC21E16A-AUT draws approximately 7 mA in active mode at 48 MHz with all peripherals enabled. Place a 100 nF X7R decoupling capacitor within 3 mm of each VDD pin and a bulk 4.7 uF tantalum or ceramic capacitor at the board supply entry. The internal core regulator on VDDCORE requires its own 1 uF ceramic capacitor placed within 2 mm of the pin. Avoid daisy-chaining VDD/VSS - use a star or power-plane topology to minimize digital switching noise coupling into the analog ADC inputs.
The 32-pin TQFP uses 0.8 mm pitch - a fine-pitch but hand-solderable package with proper technique. Use a 4-layer PCB with continuous ground plane under the MCU for best EMI and thermal performance. Keep the XIN/XOUT traces short and symmetric to minimize duty-cycle distortion on the high-frequency crystal; route them on the top layer with a guard ground on the layer below. Place the 32.768 kHz watch crystal within 5 mm of the XIN32/XOUT32 pins (PA00/PA01 in this package variant) with load capacitors sized per the crystal datasheet.
The NRST pin is active-low and is internally pulled-up; in noisy industrial environments add an external 10 kohm pull-up and 100 nF capacitor to ensure clean reset. Do not leave unused GPIO pins floating - configure them as outputs with low level or enable the internal pull. When using the USB peripheral, the internal 3.3V USB regulator requires a 1 uF decoupling capacitor on VBUS, and the D+/D- lines need 22 to 44 ohm series resistors close to the MCU pins to meet USB impedance requirements.
Compliance Information
RoHS compliant per Microchip product page. Industrial -40C to +85C temperature range; not AEC-Q100 qualified - select automotive-grade SAM C21 variants for underhood AEC-Q100 applications.
