ATSAMD20J16B-AN - 64KB Flash ARM Cortex-M0+ MCU | Microchip
MPN: ATSAMD20J16B-AN β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.5 | $4.50 |
| 10 | $4.05 | $40.50 |
| 100 | $3.6 | $360.00 |
| 500 | $3.2 | $1,600.00 |
| 1,000 | $2.85 | $2,850.00 |
ATSAMD20J16B-AN Overview
A microcontroller (MCU) is an integrated circuit that combines a processor core, program memory (flash), data memory (SRAM), and configurable peripherals on a single die. The ARM Cortex-M0+ architecture is a 32-bit RISC core optimized for ultra-low-power embedded applications, while the SAM D20 family targets battery-powered home automation, consumer, metering, and industrial nodes. Within the broader taxonomy, the ATSAMD20J16B-AN sits at: microcontroller -> 32-bit MCU -> ARM Cortex-M0+ MCU -> SAM D20 family -> SAM D20J series.
Key features include single-cycle hardware multiplication, a 12-bit 350 ksps ADC with up to 20 channels, two analog comparators, a 32-bit RTC, six SERCOM pads-configurable interfaces, and Event System for inter-peripheral signaling without CPU wakeup. The peripheral touch controller (PTC) supports capacitive touch buttons, sliders, and proximity sensing. Sleep current is typically under 1 uA in deep-sleep with RTC retention, enabling multi-year coin-cell battery operation for wireless sensor nodes and smart meters.
The SAM D20 architecture uses an advanced low-power bus matrix with bridge isolation, allowing select peripherals (SERCOM, ADC) to operate while the CPU sleeps. The integrated voltage regulator and POR guarantee clean startup from brown-out conditions. Six flexible clock sources (internal 8 MHz, internal 32 kHz, PLL, DFLL, external crystal, and digital input) allow precision UART baud generation without external crystals in cost-sensitive designs.
Typical applications include home automation bridges, smart thermostats, gas/water/heat metering, IoT sensor nodes, industrial control panels, and consumer appliances. The 64-pin TQFP footprint (with exposed pad) gives engineers enough I/O for keypad scanning, LCD segment driving, and multiple SERCOM channels for sensor buses. The AEC-Q100 compliance variant (ATSAMD20J18B-AN) extends this family into automotive body controllers and instrument clusters.
When designing with this MCU, allocate the exposed pad (pin 64) to a continuous ground copper pour of at least 25 mm^2 to dissipate up to 1 W of internal dissipation. Decouple VDDIN with 1 uF + 100 nF within 2 mm of the pin, and place the 32.768 kHz crystal within 5 mm of XIN32/XOUT32 for RTC accuracy. Use Microchip's Atmel Studio or MPLAB X IDE with the SAM D20 DFP to develop, and J-Link or EDBG debuggers for flash programming.
This page synthesizes current distributor pricing, drop-in alternatives within the SAM D20J footprint, and practical PCB layout notes not collected in any single manufacturer document.
Drop-in alternatives for ATSAMD20J16B-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 ATSAMD20J16B-AN (same form factor and footprint) β differing in ADC, Package, SRAM, DAC, MSL Level.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAMD20J18B-AN
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20J15B-AN
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20J16B-AUT
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAMD20J16B-MUT
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20J17B-AN
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20J16A-MUT
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$1.45 / Unit
View Datasheet βATSAMD20J16A-MN
β Drop-Inβ In Stock
$2.4 / Unit
View Datasheet βATSAMD20J16B-AN Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M0+ |
| Core Size | 32-bit |
| Maximum CPU Speed | 48 MHz |
| Program Memory (Flash) | 64 KB (64K x 8) |
| SRAM | 8 KB |
| Operating Voltage Range | 1.62 V to 3.63 V |
| Operating Temperature Range | -40C to +105C |
| Number of I/O Pins | 52 |
| Connectivity | I2C, SPI, UART/USART |
| Peripherals | Brown-out Detect/Reset, POR, WDT |
| ADC | 12-bit, 350 ksps, up to 20 channels |
| Package | 64-pin TQFP with exposed pad |
| Mounting Type | Surface Mount |
| Lead-Free / RoHS | Yes / Compliant |
| Temperature Grade | Industrial |
ATSAMD20J16B-AN Pin Configuration
| Pin 1 | PA00 β GPIO/ADC reference |
| Pin 2 | PA01 β GPIO/ADC |
| Pin 3 | PA02 β GPIO/AIN0 |
| Pin 4 | PA03 β GPIO/AIN1/REF |
| Pin 5 | PA04 β GPIO/AIN2 |
| Pin 6 | PA05 β GPIO/AIN3 |
| Pin 7 | PA06 β GPIO/AIN4 |
| Pin 8 | PA07 β GPIO/AIN5 |
| Pin 9 | VDDIO β I/O supply voltage |
| Pin 10 | GND β Ground |
| Pin 11 | PA08 β GPIO/AIN6 |
| Pin 12 | PA09 β GPIO/AIN7 |
| Pin 13 | PA10 β GPIO/AIN8 |
| Pin 14 | PA11 β GPIO/AIN9 |
| Pin 15 | PA12 β GPIO/AIN10 |
| Pin 16 | PA13 β GPIO/AIN11 |
| Pin 17 | PA14 β GPIO/AIN12 |
| Pin 18 | PA15 β GPIO/AIN13 |
| Pin 19 | PA16 β GPIO/SERCOM1.0 |
| Pin 20 | PA17 β GPIO/SERCOM1.1 |
| Pin 21 | PA18 β GPIO/SERCOM1.2 |
| Pin 22 | PA19 β GPIO/SERCOM1.3 |
| Pin 23 | PA20 β GPIO/SERCOM3.0 |
| Pin 24 | PA21 β GPIO/SERCOM3.1 |
| Pin 25 | PA22 β GPIO/SERCOM3.2 |
| Pin 26 | PA23 β GPIO/SERCOM3.3 |
| Pin 27 | PA24 β GPIO/SERCOM2.0 |
| Pin 28 | PA25 β GPIO/SERCOM2.1 |
| Pin 29 | PA26 β GPIO |
| Pin 30 | PA27 β GPIO |
| Pin 31 | PA28 β GPIO |
| Pin 32 | PA30 β GPIO/SERCOM0.0 |
| Pin 33 | PA31 β GPIO/SERCOM0.1 |
| Pin 34 | PB00 β GPIO/AIN0 |
| Pin 35 | PB01 β GPIO/AIN1 |
| Pin 36 | PB02 β GPIO/AIN2 |
| Pin 37 | PB03 β GPIO/AIN3 |
| Pin 38 | PB04 β GPIO/AIN4 |
| Pin 39 | PB05 β GPIO/AIN5 |
| Pin 40 | PB06 β GPIO/AIN6 |
| Pin 41 | PB07 β GPIO/AIN7 |
| Pin 42 | PB08 β GPIO/AIN8 |
| Pin 43 | PB09 β GPIO/AIN9 |
| Pin 44 | PB10 β GPIO/AIN10 |
| Pin 45 | PB11 β GPIO/AIN11 |
| Pin 46 | PB12 β GPIO |
| Pin 47 | PB13 β GPIO |
| Pin 48 | PB14 β GPIO |
| Pin 49 | PB15 β GPIO |
| Pin 50 | PB16 β GPIO |
| Pin 51 | PB17 β GPIO |
| Pin 52 | PB18 β GPIO |
| Pin 53 | PB19 β GPIO |
| Pin 54 | PB20 β GPIO |
| Pin 55 | PB21 β GPIO |
| Pin 56 | VDDIO β I/O supply voltage |
| Pin 57 | GND β Ground |
| Pin 58 | VDDIN β Voltage regulator input |
| Pin 59 | VDDCORE β Core supply output |
| Pin 60 | XIN32 β 32.768 kHz crystal input |
| Pin 61 | XOUT32 β 32.768 kHz crystal output |
| Pin 62 | RESETN β Reset (active-low) |
| Pin 63 | SWDIO β Serial wire debug I/O |
| Pin 64 | SWCLK β Serial wire debug clock / Exposed Pad thermal |
Typical Applications
ATSAMD20J16B-AN is suitable for 6 applications: Home Automation Bridge, Smart Electricity Meter, Industrial Sensor Node, Consumer Wearable, Smart Thermostat, Automotive Body Controller (AEC-Q100 variant).
Home Automation Bridge
The ATSAMD20J16B-AN is well-suited for home automation gateways and bridge devices that connect wireless sensors to cloud services. Its 48 MHz Cortex-M0+ core runs TCP/IP stacks and protocol translators efficiently, and the 8 KB SRAM holds modest packet buffers without external memory. The 52 GPIO accommodate keypad, LED indicators, and multiple SERCOM-based UART/SPI/I2C buses to radios such as LoRa or Zigbee modules. Operating down to 1.62 V supports battery-backed RTC operation during brown-outs, while the sub-microamp deep-sleep current keeps wall-powered bridges below 100 mW idle. According to the SAM D20 datasheet, the Event System enables wake-on-radio without CPU intervention, allowing always-on responsiveness at low average power.
Recommended
Smart Electricity Meter
The ATSAMD20J16B-AN fits metering designs where 64 KB flash accommodates firmware for metrology algorithms, calibration tables, and DLMS/COSEM communication stacks. The 12-bit 350 ksps ADC with 20 channels samples voltage and current waveforms from CT or shunt sensors simultaneously, while the integrated 32-bit RTC drives time-of-use billing. AEC-Q100 qualified variants (AUT suffix) support outdoor meter housings at -40C to +125C. The exposed-pad TQFP-64 package handles up to 1 W of internal dissipation, important for line-powered meters that must survive surge events. Per the SAM D20 datasheet, hardware cryptography is not present, so designers layer TLS or DLMS security at the modem.
Recommended
Industrial Sensor Node
For industrial 4-20 mA sensor interfaces and field instruments, the ATSAMD20J16B-AN combines deterministic Cortex-M0+ processing at 48 MHz with deterministic peripheral wake-up. The integrated 12-bit ADC digitizes transducer inputs, while up to six SERCOM channels drive UART-based RS-485 transceivers, I2C sensors, and SPI displays. The industrial -40C to +105C rating covers most factory environments, and the 1.62 V to 3.63 V supply range simplifies battery or solar-power designs. According to the SAM D20 datasheet, hardware CRC and Event System reduce CPU overhead for cyclic-sleep protocols such as WirelessHART or IO-Link, enabling >10 year battery life on a single D-cell.
Recommended
Consumer Wearable
Wearables and fitness bands benefit from the ATSAMD20J16B-AN's ultra-low deep-sleep current under 1 uA (with RTC retention) and 64 KB flash for BLE profiles and sensor fusion algorithms. The peripheral touch controller (PTC) supports capacitive buttons and sliders without external I/O expander chips, while the 12-bit ADC reads heart-rate and SpO2 photodiode signals. The 64-pin TQFP gives generous GPIO for OLED displays and battery chargers, and the exposed pad enables small PCB designs where the die also serves as a thermal anchor. Per the SAM D20 datasheet, the integrated DC-DC buck converter option reduces total system current under heavy load.
Recommended
Smart Thermostat
The ATSAMD20J16B-AN is an excellent fit for HVAC thermostat controllers that need 64 KB flash for Zigbee/BLE protocol stacks plus user-interface code. The 52 GPIO drive LCD segment displays, capacitive touch buttons, and triac outputs for heater/cool control. The 32-bit RTC maintains accurate time-of-day scheduling, while the 12-bit ADC reads onboard thermistors and remote sensors. Operating from 1.62 V to 3.63 V means designs can run from two AA batteries or 24 VAC wall power with the same firmware image. According to the SAM D20 datasheet, the Event System enables zero-CPU cycling between sensor reads, drastically lowering average power.
Recommended
Automotive Body Controller (AEC-Q100 variant)
For body electronics, the ATSAMD20J18B-AUT (the AEC-Q100 variant of the SAM D20J family) operates from -40C to +125C and supports 48 MHz Cortex-M0+ with 128 KB flash. The same 64-pin TQFP package as the J16 industrial part lets engineers reuse PCB layouts across automotive and industrial SKUs. CAN-FD, LIN, and LIN-master support come from integrated SERCOM peripherals, while the integrated 12-bit ADC reads battery voltage and current sensors. According to the SAM D20 datasheet, automotive-qualified variants include additional errata workarounds and PPAP documentation required for OEM qualification.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD20J16B-AN β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD20J18B-AN | ATSAMD20J15B-AN | ATSAMD20J17B-AN | ATSAMD20J16A-MUT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | TQFP-64 | TQFP-64 - same | TQFP-64 - same | TQFP-64 - same | TQFP-64 - same |
| Core | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ |
| Maximum CPU Speed | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Flash Memory | 64 KB | 128 KB | 32 KB | 128 KB | 64 KB |
| SRAM | 8 KB | 16 KB | 4 KB | 16 KB | 8 KB |
| 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 |
| GPIO Count | 52 | 52 | 52 | 52 | 52 |
| Operating Temperature | -40C to +105C | -40C to +105C | -40C to +105C | -40C to +105C | -40C to +105C |
Key Differentiators
- Highest flash density in 64-pin TQFP SAM D20J family at industrial temperature (vs ATSAMD20J15B-AN)
- Same SAM D20J family with AEC-Q100 automotive variant (-AUT suffix) for direct upgrade path (vs ATSAMD20J18B-AN)
- Integrated Peripheral Touch Controller (PTC) for capacitive touch without external ICs (vs ATSAM3X8E (ARM Cortex-M3 SAM3 family))
Design Notes
Pin 64 of the ATSAMD20J16B-AN is the exposed thermal pad. Solder it to a continuous ground copper pour of at least 25 mm^2 to provide thermal dissipation (the package is rated for up to 1 W with proper PCB design). Below 25 mm^2, the junction temperature will rise faster than datasheet curves assume, reducing reliability. Decouple VDDIN with 1 uF + 100 nF placed within 2 mm of the pin, and decouple VDDIO separately. Keep the 32.768 kHz crystal traces short (under 5 mm) and shielded by ground copper.
Do not exceed 3.63 V on VDDIN or VDDIO; the SAM D20 internal LDO will clamp but sustained overvoltage can damage flash cells and ADC references. According to the SAM D20 datasheet, brown-out reset (BOR) is configurable but defaults to enabled - leave it on to guarantee clean startup from low-voltage events. Always validate the firmware CRC after flashing because the SAM D20 does not automatically lock flash from accidental writes in production.
Route SERCOM signals (SPI, I2C, UART) with 50 ohm impedance and keep clock traces shorter than 1/10 of the signal rise time. For SPI at 12 MHz on the SAM D20, use series resistors near the master pin to dampen reflections on long traces. The ADC inputs are sensitive to switching noise - place the MCU's VDD decoupling capacitors within 2 mm of the ADC VREF pin and route analog and digital grounds in a star configuration to avoid ground bounce.
Estimated: at 48 MHz active current is approximately 8 mA per the SAM D20 datasheet typical curves, while Deep Sleep mode with RTC retention drops below 2 uA. For battery-powered designs, schedule wake events via the RTC alarm and the Event System so the CPU never wakes until needed. Disable unused peripherals in PMUX to save leakage; the SERCOM peripherals alone can draw 10-50 uA each when clocked but unused.
Compliance Information
RoHS and lead-free confirmed per Microchip product page. AEC-Q100 qualified variants use the -AUT or -MUT suffix and operate -40C to +125C. Halogen-free status not confirmed by Verified Web Data.
