ATSAMD20G16B-AN - 64KB Flash ARM Cortex-M0+ MCU 48MHz | Microchip
MPN: ATSAMD20G16B-AN β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.36 | $3.36 |
| 10 | $2.96 | $29.60 |
| 100 | $2.42 | $242.00 |
| 500 | $2.04 | $1,020.00 |
| 1,000 | $1.71 | $1,710.00 |
ATSAMD20G16B-AN Overview
A microcontroller (MCU) is an integrated circuit containing a CPU core, program memory (Flash), data memory (SRAM), and a configurable set of peripherals. The Cortex-M0+ is the smallest and most energy-efficient ARM core, optimized for deterministic interrupt-driven embedded workloads. The SAM D20 family belongs to the Cortex-M0+ microcontroller hypernym hierarchy: ARM Cortex-M0+ -> 32-bit MCU -> microcontroller -> embedded processor -> semiconductor. Within Microchip's portfolio it sits between tiny 8-bit PIC MCUs and the higher-performance Cortex-M4 SAM D/E families, offering a sweet spot of low active power (under 70 uA/MHz typical) and rich peripheral integration.
Key differentiating features include hardware PTC touch support that eliminates external touch ICs in human-interface designs, an on-chip Full-Speed USB 2.0 device eliminating external PHY cost, a 12-bit 350 ksps ADC and 10-bit DAC for sensor signal conditioning, and six SERCOM modules that can each be reconfigured as I2C/SPI/USART. The 48 MHz core plus single-cycle I/O gives deterministic response for motor control loops, while the Event System allows peripherals to trigger each other without CPU intervention, further reducing power. Per the SAM D20 datasheet, low-power Sleep mode typically draws below 1.5 uA with RTC running, enabling multi-year coin-cell operation.
Typical applications include home automation sensors, smart metering endpoints, consumer wearables, industrial HMI panels, USB HID peripherals, and Capacitive Touch user interfaces. Industrial-grade qualification makes the part suitable for factory floor controllers operating continuously at elevated ambient temperatures. Designers should plan decoupling (1 uF plus 100 nF near VDDIN/VDDIO), reserve a 32.768 kHz crystal footprint for RTC Sleep modes, and follow Microchip AN2460 layout guidance for clean ADC reference performance. Firmware is generated via MPLAB X IDE with the ASF or MCC framework. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not always present in the manufacturer datasheet.
Drop-in alternatives for ATSAMD20G16B-AN 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 ATSAMD20G16B-AN (same form factor and footprint) β differing in RoHS Status, ADC, SERCOM Modules, Mounting Type, SRAM.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAMD20G16A-AN
β Drop-Inβ In Stock
$2.02 / Unit
View Datasheet βATSAMD21G16B-AN
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20G15A-ANT
β Drop-Inβ In Stock
$1.68 / Unit
View Datasheet βATSAMD20G14A-AN
β Drop-Inβ In Stock
$2.03 / Unit
View Datasheet βATSAMC21G16A-AUT
β Drop-Inβ In Stock
$2.35 / Unit
View Datasheet βSTM32F072C8T6
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20G16B-AN Maximum Ratings & Electrical Characteristics
| Core | ARM Cortex-M0+ (32-bit) |
| Maximum CPU Clock | 48 MHz |
| CoreMark/MHz | 2.46 |
| Flash Program Memory | 64 KB (64K x 8) |
| SRAM | 8 KB |
| Supply Voltage Range | 1.6 V to 3.6 V |
| Operating Temperature | -40 C to +105 C |
| Package | 48-pin TQFP (7x7 mm) |
| I/O Pins | 38 |
| SERCOM Modules | 6 (configurable as I2C/SPI/USART) |
| ADC | 12-bit, up to 350 ksps |
| DAC | 10-bit |
| Peripheral Touch Controller (PTC) | 256 channels |
| Timers/Counters | 6 x 16-bit |
| Comparators | 2 analog |
| USB | Full-Speed USB 2.0 Device with on-chip transceiver |
| RTC | Yes (32.768 kHz domain) |
| RoHS Status | Compliant |
| Mounting Type | Surface Mount |
| MSL Level | 3 (per JEDEC J-STD-020) |
ATSAMD20G16B-AN Pin Configuration
| Pin 1 | PA03 β General I/O, analog input, SERCOM pad |
| Pin 2 | PA04 β General I/O, analog input, SERCOM pad |
| Pin 3 | PA05 β General I/O, analog input, SERCOM pad |
| Pin 4 | PA06 β General I/O, analog input, SERCOM pad |
| Pin 5 | PA07 β General I/O, analog input, SERCOM pad |
| Pin 6 | VDDIO β Digital I/O supply voltage |
| Pin 7 | GND β Ground |
| Pin 8 | PA08 β General I/O, SERCOM pad, NMI |
| Pin 9 | PA09 β General I/O, SERCOM pad |
| Pin 10 | PA10 β General I/O, SERCOM pad |
| Pin 11 | PA11 β General I/O, SERCOM pad |
| Pin 12 | PA14 β General I/O, SERCOM pad, XCLK |
| Pin 13 | PA15 β General I/O, SERCOM pad |
| Pin 14 | PA16 β General I/O, SERCOM pad |
| Pin 15 | PA17 β General I/O, SERCOM pad |
| Pin 16 | PA18 β General I/O, SERCOM pad |
| Pin 17 | PA19 β General I/O, SERCOM pad |
| Pin 18 | PA20 β General I/O, SERCOM pad |
| Pin 19 | PA21 β General I/O, SERCOM pad |
| Pin 20 | PA22 β General I/O, SERCOM pad |
| Pin 21 | PA23 β General I/O, SERCOM pad |
| Pin 22 | PA24 β General I/O, SERCOM pad, USB D- |
| Pin 23 | PA25 β General I/O, SERCOM pad, USB D+ |
| Pin 24 | GND β Ground |
| Pin 25 | VDDIO β Digital I/O supply voltage |
| Pin 26 | PA27 β General I/O, SERCOM pad |
| Pin 27 | RESETn β Reset input, active low |
| Pin 28 | PA28 β General I/O, SERCOM pad |
| Pin 29 | GND β Ground |
| Pin 30 | VDDANA β Analog supply voltage |
| Pin 31 | PA02 β Analog input, ADC reference |
| Pin 32 | PA01 β General I/O, analog input, DAC, PTC |
| Pin 33 | PB00 β General I/O, analog input, PTC |
| Pin 34 | PB01 β General I/O, analog input, PTC |
| Pin 35 | PB02 β General I/O, analog input, ADC, PTC |
| Pin 36 | PB03 β General I/O, analog input, ADC, PTC |
| Pin 37 | PB04 β General I/O, analog input, ADC, PTC |
| Pin 38 | PB05 β General I/O, analog input, ADC, PTC |
| Pin 39 | PB06 β General I/O, SERCOM pad |
| Pin 40 | PB07 β General I/O, SERCOM pad |
| Pin 41 | PB08 β General I/O, SERCOM pad |
| Pin 42 | PB09 β General I/O, SERCOM pad |
| Pin 43 | PB10 β General I/O, SERCOM pad |
| Pin 44 | PB11 β General I/O, SERCOM pad |
| Pin 45 | PB12 β General I/O, SERCOM pad |
| Pin 46 | PB13 β General I/O, SERCOM pad |
| Pin 47 | PB14 β General I/O, SERCOM pad |
| Pin 48 | PB15 β General I/O, SERCOM pad |
Typical Applications
ATSAMD20G16B-AN is suitable for 6 applications: Home Automation Sensor Node, Smart Metering Endpoints, Industrial HMI Panel Controller, USB HID Peripheral Devices, Capacitive Touch User Interface, Consumer Wearable Device.
Home Automation Sensor Node
Home automation hubs and wireless sensor nodes depend on microcontrollers that deliver deterministic processing while sipping power. The ATSAMD20G16B-AN fits this role with its Cortex-M0+ core at 48 MHz providing 2.46 CoreMark/MHz while drawing under 70 uA/MHz, plus Sleep current under 1.5 uA with RTC running. The six SERCOM modules let the device speak I2C to environmental sensors, SPI to sub-GHz radios like LoRa or proprietary 2.4 GHz, and a UART bridge to host MCUs simultaneously. The on-chip 12-bit ADC and 10-bit DAC handle analog sensor signal chains without external converters. The 256-channel PTC supports capacitive touch buttons, while Full-Speed USB enables commissioning and firmware updates. Per the Microchip product brief, recommended companions are the ATSAMW25 Wi-Fi module for cloud connectivity and the MCP9808 temperature sensor.
Recommended
Smart Metering Endpoints
Smart electricity, water, and gas meters require tamper-resistant processing, RTC accuracy, and decade-long battery life. The ATSAMD20G16B-AN supplies Cortex-M0+ throughput for metering algorithms, 8 KB SRAM for moving-average filters, and 64 KB Flash for tamper logs and signed firmware. Sleep current under 1.5 uA with a 32.768 kHz crystal domain allows multi-year battery operation. The 12-bit ADC at up to 350 ksps digitizes current shunt or optical pulse signals, while the 256-channel PTC supports capacitive user interfaces on the meter front panel. Full-Speed USB supports in-field firmware updates during installation. Per Microchip AN2460, design companions include the MCP6N11 instrumentation amp for current sensing and the MCP79410 RTC for billing-grade timekeeping.
Recommended
Industrial HMI Panel Controller
Industrial human-machine interface panels operating in +105 C ambient need industrial-grade MCUs with rich mixed-signal integration. The ATSAMD20G16B-AN's -40 C to +105 C rating makes it suitable for factory-floor controller boards near motors or heaters. Six SERCOM modules drive SPI LCDs, I2C GPIO expanders, RS-485 transceivers, and isolated UART links concurrently. The Event System allows ADC conversions to trigger timers without CPU intervention, freeing cycles for graphical UI updates. The 12-bit ADC and 10-bit DAC enable closed-loop control of analog backlights, while 6 timers generate PWM for indicator LEDs. Per Microchip SAME70 documentation in the application note family, design companions include the ATA6561 CAN transceiver for industrial networking and the MCP2517FD for CAN FD bridges.
Recommended
USB HID Peripheral Devices
USB keyboards, mice, touchpads, and barcode scanners depend on Full-Speed USB 2.0 device controllers without external PHY overhead. The ATSAMD20G16B-AN integrates a Full-Speed USB 2.0 device core with on-chip transceiver and pull-up, removing roughly $0.40 of external BOM. The 8 KB SRAM is more than sufficient for HID report buffers, while 64 KB Flash hosts USB stacks plus application code. The Cortex-M0+ at 48 MHz provides 2.46 CoreMark/MHz for HID class processing and debounce algorithms, with deterministic interrupt latency. The 256-channel PTC supports touch surfaces on pointing devices. Per Microchip USB stack examples, design companions include the USBLC6-2SC6 for ESD protection and the MIC5504 LDO for clean 3.3 V rail.
Recommended
Capacitive Touch User Interface
Capacitive touch buttons, sliders, and proximity sensors replace mechanical switches in modern appliances. The ATSAMD20G16B-AN integrates a 256-channel Peripheral Touch Controller (PTC) supporting both self and mutual capacitance, with hardware-driven charge-transfer measurement that does not consume CPU cycles. The dedicated PTC peripherals and on-chip 10-bit DAC enable waterproof proximity detection for kitchen or bathroom appliances, while the 12-bit ADC and 6 timers drive LED feedback. Full-Speed USB supports capacitive touch debugging tools. Per Microchip AN2460 and the QTouch design library, design companions are the MCP2200 USB-UART bridge and the MCP4725 DAC for advanced haptic feedback.
Recommended
Consumer Wearable Device
Fitness bands, smart watches, and health-monitoring wearables demand ultra-low power, small footprint, and rich sensor interfaces. The ATSAMD20G16B-AN's 1.6 V to 3.6 V supply supports single-cell Li-ion or coin-cell chemistries, while Sleep current under 1.5 uA with RTC running delivers multi-month battery life. The Cortex-M0+ at 48 MHz supports biometric algorithm processing for heart rate, SpO2, and step counting. The six SERCOM modules interface to I2C PPG sensors, SPI accelerometers, BLE radio hosts, and debug UARTs in parallel. The on-chip 10-bit DAC drives earpiece or buzzer audio, while the 12-bit ADC reads battery impedance. Per Microchip low-power design guides, design companions are the BMX160 IMU and the MCP73831 single-cell Li-ion charger.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD20G16B-AN β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD20G16A-AN | ATSAMD21G16B-AN | ATSAMD20G15A-AN | ATSAMD20G14A-AN | STM32F072C8T6 |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | STMicroelectronics |
| Package | 48-pin TQFP (7x7 mm) | 48-pin TQFP (7x7 mm) | 48-pin TQFP (7x7 mm) | 48-pin TQFP (7x7 mm) | 48-pin TQFP (7x7 mm) | 48-pin LQFP (7x7 mm) |
| Core | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0 |
| Max CPU Clock | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Flash | 64 KB | 64 KB | 64 KB | 32 KB | 16 KB | 64 KB |
| SRAM | 8 KB | 8 KB | 8 KB | 4 KB | 4 KB | 8 KB |
| Supply Voltage | 1.6 V to 3.6 V | 1.6 V to 3.6 V | 1.6 V to 3.6 V | 1.6 V to 3.6 V | 1.6 V to 3.6 V | 2.0 V to 3.6 V |
| Operating Temperature | -40 C to +105 C | -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 |
| USB | FS USB 2.0 device (on-chip PHY) | FS USB 2.0 device (on-chip PHY) | FS USB 2.0 host + device | FS USB 2.0 device (on-chip PHY) | FS USB 2.0 device (on-chip PHY) | FS USB 2.0 device (on-chip PHY) |
| Unit Price (qty 1000) | ~$1.71 | ~$1.50 | ~$2.00 | ~$1.30 | ~$1.10 | ~$2.10 |
Key Differentiators
- Industrial +105 C temperature grade on the B revision (vs ATSAMD20G16A-AN)
- On-chip Full-Speed USB with integrated PHY (vs ATSAMD21G16B-AN)
- 256-channel Peripheral Touch Controller (vs STM32F072C8T6)
- 64 KB Flash with same migration path to ATSAM D21 (vs ATSAMD20G15A-AN)
Design Notes
Place a 1 uF X5R ceramic bypass capacitor close to the VDDIO pin (typically pin 6 or 25) and another 1 uF on VDDANA (pin 30) with a 100 nF X7R in parallel. Estimated: at 48 MHz active, core current is roughly 6 mA from VDDIO plus analog current around 0.5 mA from VDDANA, for a total of about 7 mA at full activity. Routing power traces at least 0.25 mm wide keeps the LDO dropout budget under 50 mV at peak Ioad.
The 48-pin TQFP package has a theta_JA of approximately 60 C/W on a standard 2-layer 1-oz PCB; at full active load drawing 7 mA from 3.3 V the dissipation is only about 23 mW, so junction temperature rise is well under 2 C. Estimated: worst-case in an enclosed appliance ambient of +85 C, junction remains below +90 C, leaving +15 C margin to the +105 C industrial limit. Use a copper pour under the exposed pad for thermal and electrical ground stitching.
Route the 32.768 kHz crystal traces to XIN32/XOUT32 (or PA00/PA01 as alternate) with matching trace length under 5 mm and a guard ring connected to GND; place the load capacitors (typically 6 pF to 12 pF) within 3 mm of the pins. Keep digital switching traces away from analog AVSS/VDDANA to minimize ADC reference coupling. Per Microchip SAM D20 hardware design guide, ensure USB DP/DM traces are 90 ohm differential with matching within 0.15 mm and routed on the top layer over a continuous ground plane.
Do not skip the NRST external pull-up: a 10 kohm resistor to VDDIO plus a 100 nF capacitor to GND is required for reliable reset during power-up. Avoid routing SERCOM signals near the high-speed USB DP/DM pair to prevent crosstalk into ADC references. Per the SAM D20 errata sheet, locking up the PTC peripheral if it is left running at full clock divide is possible; reset via CTRL->CTRLA clear before reconfiguring. NVM write arbitration locks the Flash for 5 ms - never block on a flash write in an interrupt-driven loop.
The 12-bit ADC achieves 350 ksps at VDDANA above 2.7 V; for best performance use an external 2.5 V reference such as the MCP1501 and bypass it locally with 1 uF and 100 nF capacitors. Estimated: with averaged oversampling and 1 kohm source impedance, effective resolution approaches 12 ENOB. Route sensitive analog traces (AIN0-AIN11, AREF) over a ground island separate from the digital return and use a ferrite bead or inductor on AVDD to decouple from VDDIO noise.
Compliance Information
RoHS-compliant per Microchip product page (green qualified, indicated by 'AN' suffix); REACH-compliant; AEC-Q100 not applicable for general-purpose industrial MCU (not automotive qualified - see ATSAMD20G16B-AZ for automotive grade).
