ATSAMD20E16B-MU - 48MHz Cortex-M0+ MCU 64KB Flash | Microchip
MPN: ATSAMD20E16B-MU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.45 | $3.45 |
| 10 | $3.1 | $31.00 |
| 100 | $2.65 | $265.00 |
| 500 | $2.28 | $1,140.00 |
| 1,000 | $1.95 | $1,950.00 |
ATSAMD20E16B-MU Overview
What is an ARM Cortex-M0+ microcontroller? An ARM Cortex-M0+ MCU is an ultra-low-power 32-bit processor core from Arm designed for embedded applications that demand deterministic real-time response, low energy consumption, and a small silicon footprint. Within the broader taxonomy it sits as a microcontroller (MCU) -> 32-bit MCU -> ARM Cortex-M microcontroller -> Cortex-M0+ class. The ATSAMD20E16 belongs to Microchip's SAM D20 family, which positions it as a low-power, high-performance general-purpose MCU for consumer, industrial, and IoT edge nodes.
Key features of the ATSAMD20E16B-MU include 64 KB (64K x 8) of embedded flash program memory, 8 KB of SRAM, four SERCOM (serial communication interface) instances that can each be independently configured as UART/SPI/I2C, a 12-bit ADC, two analog comparators, two brown-out detectors (BOD), power-on reset (POR), a real-time clock (RTC), watchdog timer (WDT), and six timer/counter instances. The device supports Sleep, Idle, and Standby low-power modes enabling deep sub-microamp sleep currents for battery applications.
Architecturally, the ATSAMD20E16B-MU uses a single-cycle 32-bit bus matrix with separate AHB and APB bridges, giving deterministic latency on GPIO and peripheral access. The 48 MHz Cortex-M0+ core pairs with a tightly-coupled flash controller that reduces wait states on contiguous code execution, while the SERCOM blocks re-use the same silicon for I2C, SPI, or USART through a flexible pin-mux, which lets designers reassign peripherals at PCB bring-up without changing the BOM.
Typical applications include home automation nodes, smart metering, industrial sensor conditioning, low-power wearables, USB human-interface devices, and consumer electronics requiring Bluetooth or sub-GHz companion chips. The wide 1.62-3.63 V VDD range lets it operate from a single Li-ion cell or two AA cells directly.
When designing with this part, route the exposed pad (EP) to a continuous ground plane with thermal vias for EMI and thermal performance, and use Atmel Studio 7 or Microchip Studio with the DFP (device family pack) to configure the SERCOM peripheral multiplexing.
This page synthesizes distributor pricing, drop-in alternatives within the SAM D20 family, and practical design notes not consolidated on the manufacturer product page.
Drop-in alternatives for ATSAMD20E16B-MU β 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 ATSAMD20E16B-MU (same form factor and footprint) β differing in Package, ADC, MSL Level, Program Memory (Flash), SRAM.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAMD20E16B-MUT
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20E15B-MU
β Drop-Inβ In Stock
$1.1 / Unit
View Datasheet βATSAMD20E14B-MUT
β Drop-Inβ In Stock
$0.95 / Unit
View Datasheet βATSAMD20E14B-AUT
β Drop-Inβ In Stock
$1.21 / Unit
View Datasheet βATSAMD20E16B-AU
β Drop-Inβ In Stock
$1.84 / Unit
View Datasheet βATSAMD20E15B-AUT
β Drop-Inβ In Stock
$2.52 / Unit
View Datasheet βATSAMD20E16B-MU Maximum Ratings & Electrical Characteristics
| Core Architecture | ARM Cortex-M0+ |
| Maximum CPU Clock | 48 MHz |
| Program Memory (Flash) | 64 KB (64K x 8) |
| SRAM | 8 KB |
| Package | 32-pin VQFN (5x5 mm) with exposed pad |
| Operating Voltage (VDD) | 1.62 V to 3.63 V |
| I/O Pins | 26 (approx., datasheet-confirm per variant) |
| SERCOM Instances | 4 (configurable as UART/SPI/I2C) |
| ADC | 12-bit, up to 20 channels |
| Analog Comparators | 2 |
| Brown-Out Detectors | 2 |
| Timers/Counters | 6 |
| RTC | Yes, 32 kHz domain |
| Watchdog Timer | Yes |
| Operating Temperature | -40 C to +85 C (industrial) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| MSL Level | 3 (per JEDEC J-STD-020, typical for VQFN) |
ATSAMD20E16B-MU Pin Configuration
| Pin 1 | PA00 β General purpose I/O / SERCOM1 PAD0 / ADC AIN0 |
| Pin 2 | PA01 β General purpose I/O / SERCOM1 PAD1 / ADC AIN1 |
| Pin 3 | PA02 β Analog comparator input / ADC AIN2 |
| Pin 4 | PA03 β Analog comparator input / ADC AIN3 / voltage reference |
| Pin 5 | GND β Ground |
| Pin 6 | VDD β Digital supply voltage |
| Pin 7 | PA04 β General purpose I/O / SERCOM0 PAD0 / ADC AIN4 |
| Pin 8 | PA05 β General purpose I/O / SERCOM0 PAD1 / ADC AIN5 |
| Pin 9 | PA06 β General purpose I/O / SERCOM0 PAD2 / ADC AIN6 |
| Pin 10 | PA07 β General purpose I/O / SERCOM0 PAD3 / ADC AIN7 |
| Pin 11 | PA08 β General purpose I/O / SERCOM2 PAD0 |
| Pin 12 | PA09 β General purpose I/O / SERCOM2 PAD1 |
| Pin 13 | PA10 β General purpose I/O / SERCOM2 PAD2 |
| Pin 14 | PA11 β General purpose I/O / SERCOM2 PAD3 |
| Pin 15 | PA12 β General purpose I/O / SERCOM3 PAD0 |
| Pin 16 | PA13 β General purpose I/O / SERCOM3 PAD1 |
| Pin 17 | PA14 β General purpose I/O / SERCOM3 PAD2 / XIN32 |
| Pin 18 | PA15 β General purpose I/O / SERCOM3 PAD3 / XOUT32 |
| Pin 19 | PA16 β General purpose I/O / SERCOM1 PAD0 / I2S SCK |
| Pin 20 | PA17 β General purpose I/O / SERCOM1 PAD1 / I2S FS |
| Pin 21 | PA18 β General purpose I/O / SERCOM1 PAD2 / I2S MCK |
| Pin 22 | PA19 β General purpose I/O / SERCOM1 PAD3 / I2S SDO |
| Pin 23 | PA20 β General purpose I/O / SERCOM5 PAD2 |
| Pin 24 | PA21 β General purpose I/O / SERCOM5 PAD3 |
| Pin 25 | PA22 β General purpose I/O / SERCOM3 PAD0 |
| Pin 26 | PA23 β General purpose I/O / SERCOM3 PAD1 / USB D- (if supported on E variant) |
| Pin 27 | PA24 β General purpose I/O / SERCOM3 PAD2 / USB D+ (if supported on E variant) |
| Pin 28 | PA25 β General purpose I/O / SERCOM3 PAD3 |
| Pin 29 | RESET β Reset input, active-low |
| Pin 30 | SWDIO β Serial Wire Debug data |
| Pin 31 | SWCLK β Serial Wire Debug clock |
| Pin 32 | EP β Exposed pad - must be soldered to ground plane for thermal/EMC performance |
Typical Applications
ATSAMD20E16B-MU is suitable for 6 applications: Home Automation / Smart Home Hub Node, Industrial Sensor Conditioning / 4-20 mA Loop Metering, Low-Power Wearable / Fitness Tracker, Consumer HID / USB Keyboard or Mouse Controller, Smart Metering / Utility Endpoint, IoT Edge Sensor Node / Wireless Endpoint.
Home Automation / Smart Home Hub Node
The ATSAMD20E16B-MU is well-suited for home automation sensor and actuator nodes that must run for months on a coin cell or two AA batteries. Its Cortex-M0+ core at 48 MHz delivers roughly 2.46 CoreMark/mA, while Standby sleep with the 32 kHz RTC running draws only a few microamps per the SAM D20 datasheet. The four SERCOM blocks let one MCU talk I2C to a sensor, SPI to a sub-GHz radio, and UART to a debug port concurrently. With 64 KB of flash it has room for a Zigbee or BLE-soft-stack plus application logic, and the wide 1.62-3.63 V VDD range lets it run directly from a 2x AA battery pack without an LDO.
Recommended
Industrial Sensor Conditioning / 4-20 mA Loop Metering
For industrial 4-20 mA loop-powered metering and sensor conditioning, the ATSAMD20E16B-MU provides a 12-bit ADC with up to 20 channels and two analog comparators in a 32-VQFN footprint. The Cortex-M0+ core runs the metering algorithm at 48 MHz while the two BODs and the POR protect against brown-out events during loop-current dips. Standby current of only a few microamps enables loop-power budget for the MCU and a 4-20 mA transmitter simultaneously. Designers typically pair this part with a low-side current shunt and a 24-bit sigma-delta ADC for precision energy metering, while the MCU itself handles HART or Modbus protocol encoding on the SERCOM.
Recommended
Low-Power Wearable / Fitness Tracker
Wearables such as fitness bands and medical patches benefit from the ATSAMD20E16B-MU's Cortex-M0+ efficiency at 48 MHz and its deep-sleep current of only a few microamps with RTC retention. The 64 KB flash holds a BLE-soft-stack or proprietary 2.4 GHz protocol plus sensor-fusion code, while the 8 KB SRAM retains algorithm state across sleep cycles. The 32-VQFN (5x5 mm) package keeps the PCB compact enough for wristband form factors, and the 1.62-3.63 V VDD range lets a single Li-ion or Li-poly cell drive the MCU directly. Four SERCOM blocks multiplex I2C for the heart-rate sensor, SPI for the OLED display, and UART for production test concurrently.
Recommended
Consumer HID / USB Keyboard or Mouse Controller
USB Human Interface Devices such as keyboards, mice, and game controllers often use the ATSAMD20E16B-MU because of its 48 MHz Cortex-M0+ core, 64 KB flash, and flexible SERCOM peripheral set. The MCU can drive USB via an external USB-IC or, in low-speed mode, via a soft-stack on the SERCOM, while remaining GPIOs handle matrix key-scanning. The 32-VQFN (5x5 mm) package keeps the BOM small, and the wide 1.62-3.63 V VDD range runs directly from a USB 5 V rail after a 3.3V LDO. The two analog comparators can be used for battery-voltage monitoring on wireless peripherals.
Recommended
Smart Metering / Utility Endpoint
Electricity, gas, and water smart-meter endpoints leverage the ATSAMD20E16B-MU's low Standby current, RTC retention, and dual BOD for tamper detection. The 12-bit ADC and analog comparators sample CT or shunt current with adequate resolution for class-1 metering, while the 64 KB flash stores the metrology library plus a wireless protocol (Zigbee, Wireless M-Bus, or LoRa) and the 8 KB SRAM retains pulse counts across deep-sleep intervals. The 32-VQFN (5x5) package survives industrial temperature ranges and the wide VDD handles battery or harvested-power supplies typical of metering endpoints.
Recommended
IoT Edge Sensor Node / Wireless Endpoint
Edge sensor nodes for building automation, agriculture, or asset tracking deploy the ATSAMD20E16B-MU as a low-power MCU front-end that aggregates sensor data and forwards it to a companion wireless SoC. Its Cortex-M0+ core at 48 MHz runs sensor-fusion and filtering algorithms on 12-bit ADC samples, while four SERCOM blocks expose I2C/SPI/UART interfaces for environmental sensors, an IMU, and a wireless co-processor. Standby current of only a few microamps with RTC retention lets battery-powered nodes achieve multi-year lifetimes on 2x AA cells, and the 32-VQFN footprint survives outdoor temperature swings without thermal throttling.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD20E16B-MU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD20E16B-MUT | ATSAMD20E15B-MU | ATSAMD20E14B-MUT | ATSAMD20E16B-AU |
|---|---|---|---|---|---|
| Brand | 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-VQFN (5x5) - same |
| CPU Core | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ |
| Max Clock | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Flash Memory | 64 KB | 64 KB | 32 KB (-50%) | 16 KB (-75%) | 64 KB |
| SRAM | 8 KB | 8 KB | 8 KB | 4 KB (-50%) | 8 KB |
| SERCOM Instances | 4 | 4 | 4 | 4 | 4 |
| ADC Channels (12-bit) | Up to 20 | Up to 20 | Up to 20 | Up to 20 | Up to 20 |
| Operating 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 |
Key Differentiators
- Highest flash density in same-package ATSAMD20E family (vs ATSAMD20E14B-MUT)
- Same-brand ARM Cortex-M0+ MCU with CAN-FD upgrade path (vs ATSAMC20E16A-MNT)
- Tape-and-reel drop-in for SMT assembly (vs ATSAMD20E16B-MU (tray))
Design Notes
Solder the central exposed pad (EP) of the 32-VQFN (5x5 mm) package to a continuous ground plane with at least 4 thermal vias arranged in a 2x2 grid under the pad. This provides the lowest-impedance ground return for the SERCOM and ADC peripherals, and it meets the datasheet-specified thermal resistance (theta-JA) for reliable operation at industrial temperatures. Without a properly soldered EP, the part may exceed thermal limits and exhibit ADC noise or reset glitches.
Place a 1 uF X7R 0402 ceramic bypass capacitor within 2 mm of the VDD pin and a 100 nF X7R 0402 within 5 mm of the same pin. Add a bulk 10 uF ceramic or tantalum capacitor on the same rail near the IC. The 1.62-3.63 V VDD range accepts input from a single Li-ion cell via a low-Iq LDO such as MCP1700. Avoid routing high-frequency digital traces (SERCOM, SWD) under the decoupling capacitors to minimize ground bounce.
The Cortex-M0+ debug pins SWDIO and SWCLK (pins 30 and 31 in this 32-VQFN variant) must NOT be left floating if you do not intend to use SWD. Configure them as GPIO in firmware or add 100 kohm pull-ups to avoid spurious reset entry. The RESET pin is active-low and requires a 10 kohm pull-up to VDD plus a 1 nF cap to ground for production boards. SERCOM peripheral multiplexing must be configured via the PORT and PMUX registers before the SERCOM is enabled, otherwise the peripheral will not respond.
Route the 32 kHz crystal traces (XIN32 / XOUT32 on PA14/PA15) as short, symmetric, ground-guarded traces within 5 mm of the IC. Place the load capacitors (typically 12-22 pF per the datasheet crystal table) as close to the pins as possible. Keep the analog inputs (ADC AINx) routed away from digital SERCOM traces and use a separate analog ground pour if the design is ADC-noise sensitive. For EMI-sensitive applications, add a 4.7 uF bulk capacitor on the analog supply (VDDANA) pin.
When driving long cables from SERCOM-configured UART or SPI lines, add a series 33 ohm resistor near the IC pin to dampen reflections. For I2C, ensure the bus pull-ups (typically 2.2-10 kohm depending on speed and capacitance) are sized per the I2C specification - too weak pull-ups cause rise-time violations, too strong pull-ups violate the sink-current spec of 3 mA per the SAM D20 datasheet.
Compliance Information
RoHS compliant per Microchip product page. Industrial temperature grade (-40 C to +85 C). Not AEC-Q100 qualified - migrate to ATSAMx20 automotive variants for AEC-Q100 Grade 1 needs.
