ATSAMD20G16B-MUT - 32-bit Cortex-M0+ MCU, 64KB Flash, 48-QFN | Microchip
MPN: ATSAMD20G16B-MUT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.45 | $4.45 |
| 10 | $4.01 | $40.10 |
| 100 | $3.56 | $356.00 |
| 500 | $3.12 | $1,560.00 |
| 1,000 | $2.78 | $2,780.00 |
ATSAMD20G16B-MUT Overview
What is an ARM Cortex-M0+ microcontroller? An ARM Cortex-M0+ MCU is a 32-bit microcontroller built around ARM's smallest, most energy-efficient Cortex-M core, which provides Thumb-2 instruction set compatibility, single-cycle I/O access, and a deterministic interrupt controller (NVIC). It sits at the entry point of the Cortex-M family, above 8-bit microcontrollers like 8051/PIC16 and below Cortex-M3/M4/M7 cores in processing capability. The SAM D20G family adds Microchip's proprietary low-power SleepWalking peripherals, Event System, and SERCOM modules on top of the Cortex-M0+ core, positioning it as a power-optimized general-purpose MCU for connected and battery-powered applications.
Key differentiating features of the ATSAMD20G16B-MUT include 64KB of in-system programmable Flash with unique 128-bit serial number, 8KB SRAM, 48 MHz maximum CPU speed, six SERCOM channels configurable as USART/UART/SPI/I2C, a 12-bit 350 ksps ADC with up to 20 channels, a 10-bit 350 ksps DAC, and full-speed USB 2.0 device support (note: USB requires external 48 MHz clock). The integrated PTC supports up to 256 touch channels for capacitive touch buttons, sliders, and proximity sensing without external ICs.
Architecturally, the SAM D20G16 uses an event-driven design with Microchip's SleepWalking technology that allows peripherals to evaluate incoming data while the CPU remains in sleep mode, waking only on matched events. The Event System routes peripheral triggers across the chip without CPU intervention, enabling ultra-low standby current of under 1 uA with RTC running. The 48 MHz core draws roughly 7 mA/MHz active, allowing long battery life in intermittent-duty applications.
Typical applications include smart home sensor nodes (HVAC, door/window sensors), industrial metering (water/gas/electricity), consumer electronics (wearables, toys, appliances), IoT edge nodes, and human-machine interfaces (touch panels, LED control). The wide operating voltage range (1.62V to 3.63V) supports both single-cell Li-ion battery systems and 3.3V regulated industrial rails.
Designers should evaluate power budget versus peripheral set carefully: the SAM D20G16 supports SleepWalking and six Sleep modes down to <1 uA backup, but higher-speed ADC sampling or continuous USB operation will dominate the active current budget. Pin-compatible migration paths within the SAM D20/D21 families exist for higher memory or USB integration needs.
This page synthesizes distributor pricing, drop-in alternatives within the SAM D20 family, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for ATSAMD20G16B-MUT — 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 ATSAMD20G16B-MUT (same form factor and footprint) — differing in ADC, DAC, Operating Temperature, Package, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAMD20G17B-MUT
✅ Drop-In📋 Reference alternative (not in catalog)
ATSAMD20G18B-MUT
✅ Drop-In📋 Reference alternative (not in catalog)
ATSAMD20G15B-MUT
✅ Drop-In✓ In Stock
$1.38 / Unit
View Datasheet →ATSAMD20G16B-MU
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →ATSAMD21G16B-MUT
✅ Drop-In✓ In Stock
$2.05 / Unit
View Datasheet →ATSAMD20G16B-MUT Maximum Ratings & Electrical Characteristics
| Core Architecture | ARM Cortex-M0+ (32-bit) |
| Family | SAM D20G |
| Maximum CPU Frequency | 48 MHz |
| Flash Memory | 64 KB (64K x 8) |
| SRAM | 8 KB |
| Package | 48-pin QFN (7x7 mm) |
| Operating Voltage Range | 1.62 V to 3.63 V |
| Operating Temperature | -40 C to +85 C (Industrial) |
| ADC | 12-bit, up to 350 ksps, up to 20 channels |
| DAC | 10-bit, 350 ksps |
| Touch Channels (PTC) | 256 channels |
| SERCOM Modules | 6 (configurable as USART/SPI/I2C) |
| USB | Full-Speed USB 2.0 Device (requires external 48 MHz clock) |
| RTC | Yes, 32.768 kHz external crystal support |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
ATSAMD20G16B-MUT Pin Configuration
| Pin 1 | PA00 — General-purpose I/O / XIN32 |
| Pin 2 | PA01 — General-purpose I/O / XOUT32 |
| Pin 3 | PA02 — General-purpose I/O / AIN0 |
| Pin 4 | PA03 — General-purpose I/O / AIN1 / VREFA |
| Pin 5 | GND — Ground |
| Pin 6 | VDDIO — Digital I/O supply |
| Pin 7 | VDDIN — Voltage regulator input |
| Pin 8 | PA04 — General-purpose I/O / AIN2 |
| Pin 9 | PA05 — General-purpose I/O / AIN3 |
| Pin 10 | PA06 — General-purpose I/O / AIN4 |
| Pin 11 | PA07 — General-purpose I/O / AIN5 |
| Pin 12 | PA08 — General-purpose I/O / SERCOM2 PAD0 |
| Pin 13 | PA09 — General-purpose I/O / SERCOM2 PAD1 |
| Pin 14 | PA10 — General-purpose I/O / SERCOM2 PAD2 |
| Pin 15 | PA11 — General-purpose I/O / SERCOM2 PAD3 |
| 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 | GND — Ground |
| Pin 21 | PA16 — General-purpose I/O / SERCOM1 PAD0 |
| Pin 22 | PA17 — General-purpose I/O / SERCOM1 PAD1 |
| Pin 23 | PA18 — General-purpose I/O / SERCOM1 PAD2 |
| Pin 24 | PA19 — General-purpose I/O / SERCOM1 PAD3 |
| Pin 25 | PA20 — General-purpose I/O / SERCOM5 PAD2 |
| Pin 26 | PA21 — General-purpose I/O / SERCOM5 PAD3 |
| Pin 27 | PA22 — General-purpose I/O / SERCOM3 PAD0 |
| Pin 28 | PA23 — General-purpose I/O / SERCOM3 PAD1 |
| Pin 29 | PA24 — General-purpose I/O / SERCOM3 PAD2 / USB_D- |
| Pin 30 | PA25 — General-purpose I/O / SERCOM3 PAD3 / USB_D+ |
| Pin 31 | GND — Ground |
| Pin 32 | PA26 — General-purpose I/O |
| Pin 33 | PA27 — General-purpose I/O |
| Pin 34 | PA28 — General-purpose I/O |
| Pin 35 | PA29 — General-purpose I/O |
| Pin 36 | PA30 — General-purpose I/O / SWCLK |
| Pin 37 | PA31 — General-purpose I/O / SWDIO |
| Pin 38 | RESETN — Reset (active low) |
| Pin 39 | VDDIO — Digital I/O supply |
| Pin 40 | VDDIN — Voltage regulator input |
| Pin 41 | GND — Ground |
| Pin 42 | GND — Ground (exposed pad) |
| Pin 43 | VBUS — USB VBUS detect (if USB used) |
| Pin 44 | PB00 — General-purpose I/O |
| Pin 45 | PB01 — General-purpose I/O |
| Pin 46 | PB02 — General-purpose I/O / SERCOM5 PAD0 |
| Pin 47 | PB03 — General-purpose I/O / SERCOM5 PAD1 |
| Pin 48 | VDDCORE — Core voltage output (internal regulator) |
Typical Applications
ATSAMD20G16B-MUT is suitable for 6 applications: Smart Home Sensor Nodes, Industrial Metering (Water/Gas/Electricity), Capacitive Touch Human-Machine Interfaces, Consumer Wearables and Wearable Sensors, IoT Edge Nodes with BLE/Zigbee Co-processor, Low-Cost Educational and Maker Boards.
Smart Home Sensor Nodes
The ATSAMD20G16B-MUT is well suited for battery-powered smart home sensor nodes (door/window, motion, leak, HVAC) thanks to its 64KB Flash, 8KB SRAM, six SERCOM channels, and the SAM D20 family SleepWalking architecture. SleepWalking allows the ADC and PTC to evaluate incoming data while the CPU remains in sleep, enabling standby currents under 1 uA with periodic wake-ups. The 12-bit ADC and 256-channel PTC support both environmental sensing and capacitive touch buttons in the same device, eliminating the need for a separate sensor hub. Compared to switching to a higher-end Cortex-M4, the D20G keeps the BOM cost around $3 at volume while delivering sufficient MIPS for Z-Wave/Zigbee/BLE co-processor front-ends.
Recommended
Industrial Metering (Water/Gas/Electricity)
For water, gas, and electricity meters, the ATSAMD20G16B-MUT provides the analog precision, RTC capability, and low standby current required by IEC 62053-class metering designs. The integrated 12-bit ADC with 350 ksps sampling and 10-bit DAC enable signal conditioning for current transformers and flow sensors without external ADC ICs, while the 32.768 kHz RTC keeps accurate time-stamping across decades of operation. The SAM D20 Sleep modes let the MCU wake only on RTC alarm or tamper interrupts, dropping average power below the 0.5 mW budget typical for battery-backed metering. Industrial temperature grade (-40C to +85C) and the 48-QFN package also withstand meter housing thermal stress.
Recommended
Capacitive Touch Human-Machine Interfaces
The ATSAMD20G16B-MUT's integrated 256-channel Peripheral Touch Controller (PTC) directly drives capacitive buttons, sliders, wheels, and proximity sensors without a dedicated touch IC. This makes it ideal for kitchen appliances, industrial control panels, and consumer products where adding a separate touch controller would inflate BOM and PCB area. The PTC cooperates with the SAM D20 Event System to wake the CPU only on validated touch events, keeping idle power minimal even on panels with 20+ electrodes. The 64KB Flash comfortably hosts Microchip's QTouch library and a lightweight UI state machine.
Recommended
Consumer Wearables and Wearable Sensors
For fitness bands, smart watches, and wearable health sensors, the ATSAMD20G16B-MUT's 48 MHz Cortex-M0+ core, 8KB SRAM, and 12-bit ADC deliver sufficient processing for heart-rate, SpO2, and IMU data fusion at low power. The 1.62V to 3.63V supply range works directly off a single Li-ion or Li-polymer cell, while SleepWalking peripherals let the CPU stay asleep between sample windows. The 48-QFN's 7x7 mm footprint fits inside wristband form factors, and the industrial temperature grade handles skin-temperature thermal loads. Compared to a Cortex-M4 part, the M0+ cuts active current roughly in half at the same clock speed.
Recommended
IoT Edge Nodes with BLE/Zigbee Co-processor
The ATSAMD20G16B-MUT functions as the application processor in IoT edge nodes, paired with a BLE or 802.15.4 co-processor over UART or SPI. The six SERCOM channels let the MCU concurrently drive a BLE module (UART), an SPI sensor, an I2C environmental sensor, and an I2C EEPROM without pin sharing. The 64KB Flash accommodates BLE stack pass-through logic, sensor processing, and OTA bootloaders in a single image, while the 8KB SRAM buffers sensor frames before forwarding to the radio. Designers appreciate that this MCU needs no external clock for the radio hand-off, simplifying BOMs for connected sensor products.
Recommended
Low-Cost Educational and Maker Boards
The ATSAMD20G16B-MUT appears on Microchip's Curiosity Nano, Arduino Zero derivative boards, and various Adafruit/ SparkFun dev boards, making it a proven platform for maker and educational use. The 48 MHz Cortex-M0+ delivers enough compute to teach embedded C/C++ programming while keeping toolchain costs low (free Atmel Studio / MPLAB X). Native USB on the SAM D21 sibling and SWD debug headers let instructors cover everything from GPIO to interrupt-driven serial in a single semester. The 64KB Flash accommodates Microchip's START project templates and Adafruit_SAMD core Arduino libraries out of the box.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD20G16B-MUT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD20G17B-MUT | ATSAMD20G18B-MUT | ATSAMD20G15B-MUT | ATSAMD20G16B-MU | ATSAMD21G16B-MUT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 48-QFN (7x7 mm) | 48-QFN (7x7 mm) - same | 48-QFN (7x7 mm) - same | 48-QFN (7x7 mm) - same | 48-QFN (7x7 mm) - same | 48-QFN (7x7 mm) - same |
| Core | Cortex-M0+ 48 MHz | Cortex-M0+ 48 MHz | Cortex-M0+ 48 MHz | Cortex-M0+ 48 MHz | Cortex-M0+ 48 MHz | Cortex-M0+ 48 MHz |
| Flash | 64 KB | 128 KB | 256 KB | 32 KB | 64 KB | 64 KB |
| SRAM | 8 KB | 16 KB | 32 KB | 4 KB | 8 KB | 8 KB |
| USB | Yes (ext clock required) | Yes (ext clock required) | Yes (ext clock required) | Yes (ext clock required) | Yes (ext clock required) | Yes (internal DFLL) |
| SERCOM Count | 6 | 6 | 6 | 6 | 6 | 6 |
| Operating Temp | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Packaging | Tape & Reel | Tape & Reel | Tape & Reel | Tape & Reel | Tray | Tape & Reel |
Key Differentiators
- Memory upgrade path within identical 48-QFN footprint (vs ATSAMD20G15B-MUT)
- Industrial temperature grade with low power SleepWalking (vs Generic Cortex-M0+ MCU)
- Integrated 256-channel PTC eliminates external touch IC (vs Cortex-M0+ MCU without PTC)
Design Notes
Estimated: At 48 MHz active, the SAM D20G16 draws approximately 7 mA from a 3.3V supply. In Standby mode with RTC running, current drops to under 1.5 uA. For battery-powered designs, gate the MCU's VDDIN via a load switch and put the application in Standby between interrupts to extend coin-cell life. The SAM D20 also supports a 32.768 kHz external crystal on PA00/PA01 for RTC accuracy; ensure load capacitor values match the crystal's CL spec (typically 7 pF).
The 48-QFN (7x7 mm) package has an exposed thermal pad (EP) on pin 42 that must be soldered to a PCB ground pour for thermal and electrical performance. Stitch the EP to the GND plane with a 3x3 via array (0.3 mm via diameter, 0.6 mm pitch) to keep thermal resistance low. Place the 1 uF VDDIN and VDDIO bypass capacitors within 2 mm of their respective pins, with the VDDCORE capacitor (1 uF X7R) within 1 mm of pin 48.
Common pitfall: assuming the SAM D20 USB works without an external 48 MHz clock. The SAM D20 family datasheet (DS60001504E) explicitly states USB requires an external 48 MHz crystal or oscillator on PA24/PA25; the SAM D20 lacks an internal 48 MHz PLL/DFLL. If your design needs USB, either add the external clock or migrate to the SAM D21 family (e.g., ATSAMD21G16B-MUT) which integrates the 48 MHz DFLL.
When routing SERCOM peripherals as SPI at speeds above 12 MHz, add source-series termination (22-33 ohm) on the SCK, MOSI, and chip-select traces to dampen reflections on the 48-QFN's bond-wire inductance. Keep SPI trace lengths under 50 mm and avoid routing parallel to switching power traces. The 48-QFN's center-bond-wire structure gives the worst-case signal pins (PA00-PA31) slightly higher inductance than LQFP packages, which matters for SPI/QSPI speeds above 24 MHz.
Estimate: Place the SWD header (SWCLK on PA30, SWDIO on PA31) on the same edge as the RESETN pin (pin 38) to simplify debugger mechanical alignment on the Curiosity Nano footprint. Use a 1.27 mm pitch 10-pin Cortex Debug header for compatibility with Microchip's EDBG-based debuggers. Avoid routing analog signals (PA02-PA07) directly under the SWD clock trace to prevent coupling into the ADC readings.
Compliance Information
RoHS and REACH compliance confirmed via Microchip product page. The ATSAMD20G16B-MUT is not AEC-Q100 qualified; for automotive applications use the SAM D20xA or SAM D21xA variants that carry AEC-Q100.