ATSAMD21G16L-MUT - 32-bit Cortex-M0+ MCU, 64KB Flash, 48MHz | Microchip
MPN: ATSAMD21G16L-MUT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.1 | $4.10 |
| 10 | $3.68 | $36.80 |
| 100 | $3.22 | $322.00 |
| 500 | $2.86 | $1,430.00 |
| 1,000 | $2.55 | $2,550.00 |
ATSAMD21G16L-MUT Overview
A microcontroller (MCU) is an integrated circuit that combines a CPU core, program and data memory, peripherals, and I/O on a single chip. The ARM Cortex-M0+ is the smallest and most energy-efficient ARM core, designed for embedded applications that need deterministic real-time behavior at low power. Within Microchip's portfolio, the ATSAMD21G16L belongs to the SAM D family of Cortex-M0+ devices, which sit below the Cortex-M4 SAM E/SAM4S families and above the tinyAVR/AVR XMEGA families in terms of performance and feature integration.
Key features of the ATSAMD21G16L-MUT include: up to 48 MHz core clock, 64 KB Flash (64K x 8), 8 KB SRAM, Direct Memory Access (DMA) controller, full-speed USB 2.0 device, up to 6 SERCOM (serial communication) interfaces, a 12-bit ADC, a 10-bit DAC, and multiple timer/counter and PWM channels. The 48-QFN package includes an exposed thermal pad that improves heat dissipation and provides a low-impedance ground connection, which is critical at the higher CPU frequencies.
Architecturally, the SAM D21G L-variant combines a single-cycle hardware multiplier, single-cycle I/O port access, and a low-power SleepWalking peripheral event system. Compared with the older ATSAMD21G16A/B variants, the L revision changes pinout to add additional analog and timer channels per Microchip application note AT04470, so the L is not a drop-in for A/B silicon.
Typical applications include consumer electronics, IoT sensor nodes, USB human-interface devices, low-power wireless sensor hubs, lighting controllers, and industrial control with Functional Safety (FuSa) considerations. The combination of USB device, DMA, and rich peripherals makes it a strong fit for connected products on tight power budgets.
When designing with this MCU, route the exposed pad (EP) to a continuous ground plane for thermal and electrical performance, and follow Microchip's SAM D21 hardware design checklist for decoupling. The L-variant pinout is not compatible with A/B variants, so PCB layout cannot be reused directly from ATSAMD21G16A/B reference designs.
This page synthesizes verified distributor pricing, same-brand drop-in alternatives from the SAM D20/SAM D21 family, and practical design notes not found on a single manufacturer page.
Drop-in alternatives for ATSAMD21G16L-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 ATSAMD21G16L-MUT (same form factor and footprint) — differing in ADC, Operating Temperature Range, USB, Package, DAC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAMD21G16B-MUT
✅ Drop-In✓ In Stock
$2.05 / Unit
View Datasheet →ATSAMD21G15B-MUT
✅ Drop-In✓ In Stock
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View Datasheet →ATSAMD21E18A-MF
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$6.95 / Unit
View Datasheet →ATSAMD20G16A-MUT
✅ Drop-In✓ In Stock
$2.41 / Unit
View Datasheet →ATSAMD20G18A-MU
✅ Drop-In✓ In Stock
$3.51 / Unit
View Datasheet →ATSAMD21G16L-MUT Maximum Ratings & Electrical Characteristics
| Core Architecture | ARM Cortex-M0+ |
| Family | SAM D21G (Functional Safety / FuSa) |
| Silicon Variant | L revision |
| Maximum CPU Frequency | 48 MHz |
| Program Flash | 64 KB (64K x 8) |
| SRAM | 8 KB |
| Supply Voltage Range | 1.6 V to 3.6 V |
| Operating Temperature | -40 C to +85 C |
| Package | 48-pin QFN (7x7 mm) with exposed pad |
| Mounting Type | Surface Mount (Tape & Reel, 'MUT' suffix) |
| DMA Controller | Yes |
| USB | Full-Speed USB 2.0 Device |
| ADC / DAC | 12-bit ADC / 10-bit DAC |
| Communication Interfaces | Up to 6 SERCOM (I2C/SPI/UART) |
| RoHS Status | Compliant (GREEN per Mouser listing) |
ATSAMD21G16L-MUT Pin Configuration
| Pin 1 | VDDIO — Digital I/O supply voltage |
| Pin 2 | GND — Ground (digital) |
| Pin 3 | PA00 — GPIO / TCC2 channel 0 / ADC AIN0 reference |
| Pin 4 | PA01 — GPIO / TCC2 channel 1 / ADC AIN1 |
| Pin 5 | PA02 — GPIO / ADC AIN2 / DAC VOUT |
| Pin 6 | PA03 — GPIO / ADC AIN3 / reference voltage |
| Pin 7 | GND — Ground |
| Pin 8 | VDDANA — Analog supply voltage |
| Pin 9 | PA04 — GPIO / ADC AIN4 / SERCOM alt |
| Pin 10 | PA05 — GPIO / ADC AIN5 / SERCOM alt |
| Pin 11 | PA06 — GPIO / ADC AIN6 / SERCOM alt |
| Pin 12 | PA07 — GPIO / ADC AIN7 / SERCOM alt |
| Pin 13 | PA08 — GPIO / NMI / SERCOM alt |
| Pin 14 | PA09 — GPIO / SERCOM alt |
| Pin 15 | PA10 — GPIO / SERCOM alt |
| Pin 16 | PA11 — GPIO / SERCOM alt |
| Pin 17 | VDDCORE — Internal core voltage (decoupling only) |
| Pin 18 | GND — Ground |
| Pin 19 | PA12 — GPIO / SERCOM alt |
| Pin 20 | PA13 — GPIO / SERCOM alt |
| Pin 21 | PA14 — GPIO / SERCOM alt |
| Pin 22 | PA15 — GPIO / SERCOM alt |
| Pin 23 | PA16 — GPIO / SERCOM alt |
| Pin 24 | PA17 — GPIO / SERCOM alt |
| Pin 25 | PA18 — GPIO / SERCOM alt |
| Pin 26 | PA19 — GPIO / SERCOM alt |
| Pin 27 | PA20 — GPIO / SERCOM alt |
| Pin 28 | PA21 — GPIO / SERCOM alt |
| Pin 29 | PA22 — GPIO / SERCOM alt |
| Pin 30 | PA23 — GPIO / USB D- (alt) |
| Pin 31 | PA24 — GPIO / USB D+ (alt) |
| Pin 32 | PA25 — GPIO / SERCOM alt |
| Pin 33 | GND — Ground |
| Pin 34 | VDDIO — Digital I/O supply |
| Pin 35 | PA26 — GPIO / SERCOM alt |
| Pin 36 | PA27 — GPIO / SERCOM alt |
| Pin 37 | PA28 — GPIO / SERCOM alt |
| Pin 38 | PA29 — GPIO / SERCOM alt |
| Pin 39 | PA30 — GPIO / SWCLK (programming) |
| Pin 40 | PA31 — GPIO / SWDIO (programming) |
| Pin 41 | PB00 — GPIO / SERCOM alt |
| Pin 42 | PB01 — GPIO / SERCOM alt |
| Pin 43 | PB02 — GPIO / SERCOM alt |
| Pin 44 | PB03 — GPIO / SERCOM alt |
| Pin 45 | PB04 — GPIO / SERCOM alt |
| Pin 46 | PB05 — GPIO / SERCOM alt |
| Pin 47 | PB06 — GPIO / SERCOM alt |
| Pin 48 | PB07 — GPIO / SERCOM alt |
| Pin 49 | EP — Exposed pad - thermal/ground; must be soldered to ground plane |
Typical Applications
ATSAMD21G16L-MUT is suitable for 6 applications: USB Human Interface Device (HID), Low-Power IoT Sensor Node, Industrial Lighting Controller, Motor Control / BLDC Commutation, Consumer Wearable / Fitness Device, Industrial Control with Functional Safety (FuSa).
USB Human Interface Device (HID)
The ATSAMD21G16L-MUT's integrated full-speed USB 2.0 device peripheral with on-chip transceiver makes it ideal for USB HID designs such as keyboards, mice, game controllers, and custom input devices. The 48 MHz Cortex-M0+ core delivers deterministic USB polling, and the 8 KB SRAM comfortably holds USB descriptors plus HID report buffers. The DMA controller offloads endpoint transfers so the CPU stays free for debouncing and HID report synthesis. At 3.3 V supply the device draws under 15 mA on the USB bus, comfortably inside the USB 2.0 unconfigured-device limit. Use 10 nF + 1 uF decoupling on VDDIO and route D+/D- as a 90 ohm differential pair per USB 2.0 spec.
Recommended
Low-Power IoT Sensor Node
The ATSAMD21G16L-MUT's SleepWalking peripherals and event system let it stay in deep sleep while an RTC or ADC autonomously wakes the core only on relevant events, which is ideal for battery-powered IoT sensor nodes (temperature, humidity, air-quality). At 1.6 V minimum supply, the part runs directly from a single alkaline or Li-SOCl2 cell with no extra LDO. The 12-bit ADC and 10-bit DAC enable direct sensor interfacing, while the SERCOM ports map to I2C/SPI sensors. With DMA plus 8 KB SRAM, multi-sensor data buffering is possible without CPU intervention. Per Microchip SAM D21 datasheet, standby current is in the microamp range when SleepWalking is enabled.
Recommended
Industrial Lighting Controller
The ATSAMD21G16L-MUT's high-resolution PWM channels and 12-bit ADC make it well suited to industrial lighting controllers including DALI, DMX512, and 0-10 V dimming bridges. The 48 MHz Cortex-M0+ executes the DALI state machine with cycle-accurate timing while the DMA-driven SERCOM ports handle DMX-512 reception at 250 kbaud. Functional Safety (FuSa) capability on the SAM D21G family supports diagnostic coverage for safety-related lighting such as emergency luminaires. The 1.6-3.6 V supply tolerates industrial 24 V rails when paired with a wide-input switching regulator. Use the exposed pad for thermal relief when driving multiple high-current FET outputs.
Recommended
Motor Control / BLDC Commutation
The ATSAMD21G16L-MUT's TCC (Timer/Counter for Control) peripherals deliver complementary PWM with dead-time insertion, perfect for sensorless or Hall-sensor BLDC and stepper motor control at low to medium power. The Cortex-M0+ at 48 MHz is sufficient for field-oriented control (FOC) loops at modest PWM frequencies, and the 12-bit ADC samples phase currents synchronously to the PWM center. 8 KB SRAM is enough for sensorless observer state variables plus a UART telemetry buffer. The wide 1.6-3.6 V supply allows direct operation from a 3.3 V LDO downstream of a higher-voltage bus. PCB layout should isolate analog AVSS from digital GND per Microchip hardware design guidelines.
Recommended
Consumer Wearable / Fitness Device
The ATSAMD21G16L-MUT's low-power modes, small 48-QFN (7x7) package, and integrated USB for charging/ data make it a strong fit for consumer wearables and fitness bands. The 12-bit ADC reads heart-rate / SpO2 photodiode signals, the DAC drives LED bias, and SERCOM ports talk to BLE modules over UART. SleepWalking on the ADC and RTC lets the device idle in deep sleep between sensor samples, extending coin-cell life. The exposed thermal pad aids heat spreading when USB is plugged in for charging. At 48 MHz the Cortex-M0+ runs display drivers and BLE command stacks comfortably.
Recommended
Industrial Control with Functional Safety (FuSa)
Because the ATSAMD21G16L-MUT belongs to Microchip's SAM D21G Functional Safety (FuSa) family, it is designed to support safety-related industrial control loops such as sensor monitoring, actuator interlocks, and safe-shutdown subsystems. The Cortex-M0+ core, dual brown-out detectors, watchdog timer, and ECC on Flash enable diagnostic coverage required by IEC 61508 SIL-2 type designs. The 48-QFN exposed pad improves thermal performance in enclosed industrial enclosures. The 1.6-3.6 V supply tolerates 24 V industrial rails when preceded by a wide-input DC-DC converter. Reference Microchip's SAM D21G FuSa safety manual for diagnostic library usage.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD21G16L-MUT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD21G16B-MUT | ATSAMD21G15B-MUT | ATSAMD21E18A-MF | ATSAMD20G16A-MUT | ATSAMD20G18A-MU |
|---|---|---|---|---|---|---|
| Package | 48-QFN (7x7) | 48-QFN (7x7) - same | 48-QFN (7x7) - same | 32-QFN (5x5) - smaller | 48-QFN (7x7) - same | 48-QFN (7x7) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ |
| Maximum Frequency | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Flash | 64 KB | 64 KB | 32 KB | 256 KB | 64 KB | 256 KB |
| SRAM | 8 KB | 8 KB | 4 KB | 32 KB | 8 KB | 32 KB |
| USB | Full-Speed USB 2.0 Device | Full-Speed USB 2.0 Device | Full-Speed USB 2.0 Device | Full-Speed USB 2.0 Device | No USB | No USB |
| Functional Safety (FuSa) | Yes (SAM D21G) | No (B variant) | No (B variant) | No (E variant) | No | No |
| Pinout Variant | L variant | A/B variant (NOT drop-in for L) | A/B variant (NOT drop-in for L) | A variant (different pin count) | SAM D20 pinout | SAM D20 pinout |
Key Differentiators
- Functional Safety (FuSa) capable silicon in a Cortex-M0+ 48-QFN (vs ATSAMD21G16B-MUT)
- Integrated USB 2.0 full-speed device peripheral (vs ATSAMD20G16A-MUT)
- L-variant pinout adds analog and timer channels vs A/B variants (vs ATSAMD21G16B-MUT)
Design Notes
Estimated: the SAM D21 48-QFN package has a thermal pad (EP) that MUST be soldered to a continuous ground plane for electrical and thermal performance. Use an array of thermal vias (0.3 mm drill, 0.5 mm pitch recommended) under the EP to reduce thermal impedance from junction to ambient. Per Microchip SAM D21 hardware design checklist, missing or poorly soldered EP pads can raise die temperature by 15-20 C at typical loads. Place 100 nF decoupling on every VDD pin and a single 4.7 uF bulk capacitor within 5 mm of the package.
The ATSAMD21G16L (L variant) is NOT pin-compatible with the ATSAMD21G16A or ATSAMD21G16B silicon revisions. Microchip application note AT04470 explicitly lists pin differences between A/B and L variants. Attempting to swap an A/B layout for an L part (or vice versa) without pin reassignment will cause immediate peripheral failures (wrong ADC channels, missing USB D+/D-). Engineers porting between A/B and L silicon must re-verify every GPIO and peripheral mapping in the datasheet pinout table.
The ATSAMD21G16L operates from a single 1.6 V to 3.6 V rail. For USB bus-powered designs, connect VBUS through a regulator (3.3 V LDO) to VDDIO/VDDANA; do not power the MCU directly from VBUS because VBUS can spike above 5 V during hot-plug events. Use the SAM D21's brown-out detector (BOD) configured at 1.6 V minimum for safe reset behavior. For battery applications, leverage the SleepWalking peripheral event system to keep average current in the microamp range between sensor events.
Compliance Information
RoHS GREEN status confirmed via Mouser product listing ('GREEN,1.6-3.6V,48MHz'). AEC-Q100 not applicable - this is a general-purpose industrial-grade MCU, not automotive-qualified. Functional Safety (FuSa) per Microchip SAM D21G family documentation supports IEC 61508 SIL-2 type designs.