ATSAMC20J18A-AUT - 256KB Flash Cortex-M0+ MCU | Microchip
MPN: ATSAMC20J18A-AUT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.2 | $5.20 |
| 10 | $4.65 | $46.50 |
| 100 | $4.1 | $410.00 |
| 500 | $3.55 | $1,775.00 |
| 1,000 | $3.1 | $3,100.00 |
ATSAMC20J18A-AUT Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, memory (Flash for code, SRAM for data), peripherals, and I/O onto one silicon die. The ARM Cortex-M0+ is the most energy-efficient core in the Cortex-M family, designed for deterministic embedded control with Thumb-2 instruction set, hardware single-cycle multiply, and a Nested Vectored Interrupt Controller (NVIC). The SAM C20 family extends this core with 5V tolerance, CAN-FD support, and Microchip's Peripheral Touch Controller (PTC), making the part a natural fit for industrial automation, appliance control, and automotive body electronics where 5V rails still dominate.
Key features include the Cortex-M0+ core at 48 MHz delivering 38 CoreMark, integrated CAN-FD controller, full-speed USB device, up to six SERCOM serial interfaces, a 12-bit 1 Msps ADC, a 16-bit Sigma-Delta ADC support path, two analog comparators, and a 24-channel PTC for capacitive touch sensing. The 256 KB Flash supports in-application programming via the bootloader ROM, and 32 KB SRAM is sufficient for protocol stacks such as CANopen or Modbus alongside application logic. The device also includes a 32-bit real-time clock, multiple timer/counters (TCC), and a Parallel Capture Controller for signal measurement.
The architecture pairs the Cortex-M0+ core with Microchip's peripheral bus matrix that gives DMA access to every major peripheral, offloading data movement from the CPU. Hardware dividers run at full clock speed, and the 2.7V to 5.5V range is regulated internally to the 1.2V core domain, simplifying external power design to a single bulk rail. The 64-pin TQFP (10x10 mm) package provides 52 GPIO with 5V tolerance, suitable for moderate I/O count systems with mixed analog/digital signal exposure.
Typical applications include industrial sensor transmitters, appliance control boards, CAN node endpoints (especially with CAN-FD upgrade path), USB device peripherals, low-power IoT edge nodes, and motor control complements to a dedicated motor MCU. The AEC-Q100 qualified versions of the family are used in automotive body and chassis modules where 5V tolerance is mandatory.
When designing with this device, allocate 4 KB of Flash for the Atmel/Microchip SAM-BA bootloader if USB firmware updates are needed, and provision a 32.768 kHz crystal on the XIN32/XOUT32 pins for accurate RTC timekeeping. The device's 5V tolerance is a real differentiator versus 3.3V-only Cortex-M0+ parts from competing families.
This page synthesizes distributor pricing, drop-in alternatives from the same SAM C20 family, and practical design notes not found in the manufacturer datasheet, optimized for engineers evaluating the ATSAMC20J18A-AUT for a 5V industrial design.
Drop-in alternatives for ATSAMC20J18A-AUT — 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 ATSAMC20J18A-AUT (same form factor and footprint) — differing in ADC, Package, Core Architecture, RoHS Status, DAC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAMC20J17A-AUT
✅ Drop-In✓ In Stock
$3.16 / Unit
View Datasheet →ATSAMC20J16A-AUT
✅ Drop-In✓ In Stock
$1.82 / Unit
View Datasheet →ATSAMC20J16A-MUT
✅ Drop-In✓ In Stock
$2.25 / Unit
View Datasheet →ATSAMC20E18A-AUT
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →ATSAMC20J18A-AUT Maximum Ratings & Electrical Characteristics
| Core | ARM Cortex-M0+ (32-bit, single-core) |
| Maximum Clock Speed | 48 MHz |
| Program Memory (Flash) | 256 KB (256K x 8) |
| SRAM | 32 KB |
| Operating Voltage Range | 2.7 V to 5.5 V |
| I/O Tolerance | 5 V tolerant |
| GPIO Count | 52 (on 64-pin TQFP) |
| ADC | 12-bit, up to 1 Msps |
| Analog Comparators | 2 |
| PTC (Touch Channels) | Up to 24 |
| CAN | CAN-FD controller |
| USB | Full-Speed USB Device |
| SERCOM | Up to 6 configurable serial interfaces |
| Package | 64-pin TQFP (10x10 mm) |
| Operating Temperature (Industrial) | -40 C to +85 C |
| Operating Temperature (Automotive) | -40 C to +125 C (AEC-Q100 grades available in family) |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant (Green) |
ATSAMC20J18A-AUT Pin Configuration
| Pin 1 | PA00 — GPIO / XIN32 (32.768 kHz crystal input) |
| Pin 2 | PA01 — GPIO / XOUT32 (32.768 kHz crystal output) |
| Pin 3 | VDDIO — I/O supply voltage |
| Pin 4 | GND — Ground |
| Pin 5 | PA02 — GPIO / AIN0 (ADC input) |
| Pin 6 | PA03 — GPIO / AIN1 (ADC input) |
| Pin 7 | VDDIO — I/O supply voltage |
| Pin 8 | GND — Ground |
| Pin 9 | PA04 — GPIO / AIN2 / VREFA |
| Pin 10 | PA05 — GPIO / AIN3 |
| Pin 11 | PA06 — GPIO / AIN4 / ACMP0 IN+ |
| Pin 12 | PA07 — GPIO / AIN5 / ACMP0 IN- |
| Pin 13 | VDDIO — I/O supply voltage |
| Pin 14 | GND — Ground |
| Pin 15 | PA08 — GPIO / AIN6 / SERCOM0 PAD0 |
| Pin 16 | PA09 — GPIO / AIN7 / SERCOM0 PAD1 |
| Pin 17 | PA10 — GPIO / AIN8 / SERCOM0 PAD2 |
| Pin 18 | PA11 — GPIO / AIN9 / SERCOM0 PAD3 |
| Pin 19 | PA12 — GPIO / CAN RX |
| Pin 20 | PA13 — GPIO / CAN TX |
| Pin 21 | PA14 — GPIO / XIN (main crystal input) |
| Pin 22 | PA15 — GPIO / XOUT (main crystal output) |
| Pin 23 | PA16 — GPIO / SERCOM1 PAD0 |
| Pin 24 | PA17 — GPIO / SERCOM1 PAD1 |
| Pin 25 | PA18 — GPIO / SERCOM1 PAD2 |
| Pin 26 | PA19 — GPIO / SERCOM1 PAD3 |
| Pin 27 | PA20 — GPIO / SERCOM3 PAD0 |
| Pin 28 | PA21 — GPIO / SERCOM3 PAD1 |
| Pin 29 | PA22 — GPIO / SERCOM3 PAD2 |
| Pin 30 | PA23 — GPIO / SERCOM3 PAD3 |
| Pin 31 | VDDIO — I/O supply voltage |
| Pin 32 | GND — Ground |
| Pin 33 | PA24 — GPIO / USB DP |
| Pin 34 | PA25 — GPIO / USB DM |
| Pin 35 | PA26 — GPIO |
| Pin 36 | PA27 — GPIO |
| Pin 37 | PA28 — GPIO |
| Pin 38 | PA29 — GPIO |
| Pin 39 | PA30 — GPIO / SWCLK (debug clock) |
| Pin 40 | PA31 — GPIO / SWDIO (debug data) |
| Pin 41 | PB00 — GPIO |
| Pin 42 | PB01 — GPIO |
| Pin 43 | PB02 — GPIO / SERCOM5 PAD0 |
| Pin 44 | PB03 — GPIO / SERCOM5 PAD1 |
| Pin 45 | PB04 — GPIO / SERCOM5 PAD2 |
| Pin 46 | PB05 — GPIO / SERCOM5 PAD3 |
| Pin 47 | PB06 — GPIO |
| Pin 48 | PB07 — GPIO |
| Pin 49 | PB08 — GPIO |
| Pin 50 | PB09 — GPIO |
| Pin 51 | PB10 — GPIO |
| Pin 52 | PB11 — GPIO |
| Pin 53 | PB12 — GPIO / PTC Y-line |
| Pin 54 | PB13 — GPIO / PTC X-line |
| Pin 55 | PB14 — GPIO / PTC X-line |
| Pin 56 | PB15 — GPIO / PTC Y-line |
| Pin 57 | PB16 — GPIO / PTC X-line |
| Pin 58 | PB17 — GPIO / PTC Y-line |
| Pin 59 | VDDIO — I/O supply voltage |
| Pin 60 | GND — Ground |
| Pin 61 | VDDCORE — Internal core voltage (decoupling) |
| Pin 62 | VDDIN — Main voltage regulator input |
| Pin 63 | NRST — Reset input (active low) |
| Pin 64 | GND — Ground |
Typical Applications
ATSAMC20J18A-AUT is suitable for 6 applications: Industrial Sensor Transmitter, Appliance Control Board, CAN-FD Automotive Body Module, USB Device Peripheral, Capacitive Touch User Interface, Battery-Powered IoT Edge Node.
Industrial Sensor Transmitter
The ATSAMC20J18A-AUT's 5V-tolerant GPIO and CAN-FD controller make it well-suited for industrial 4-20 mA loop-powered sensor transmitters and CAN nodes. The 12-bit 1 Msps ADC digitizes bridge sensors directly without external amplifier chains, while 32 KB SRAM holds CANopen or Modbus RTU protocol buffers alongside calibration coefficients. Operated from a single 5V rail with no level-shifters required, the device reduces BOM complexity and PCB area. The 48 MHz Cortex-M0+ core runs one-step digital filtering, linearization, and HART-style burst modulation within tight loop-update deadlines under 10 ms.
Recommended
Appliance Control Board
The ATSAMC20J18A-AUT is an ideal main controller for washing machines, dishwashers, and HVAC appliances where 5V triac drivers and 5V display interfaces dominate the BOM. With up to 52 GPIO in the 64-pin TQFP, the MCU can directly drive relay coils, encoder wheels, and 7-segment LED displays without external logic. The 24-channel Peripheral Touch Controller (PTC) supports capacitive user interfaces for waterproof button panels. 256 KB Flash fits motor-control state machines plus safety watchdog logic, and the Cortex-M0+ deterministic interrupt latency ensures reliable control-loop timing on a 5V industrial rail.
Recommended
CAN-FD Automotive Body Module
The ATSAMC20J18A-AUT's CAN-FD controller and 5V I/O tolerance match the requirements of automotive body controllers including body control modules, door modules, and seat controllers that still use 5V sensors. The 256 KB Flash hosts CAN stack, diagnostics (UDS), and signal-processing firmware; the 32 KB SRAM keeps CAN-FD message buffers without external RAM. The Cortex-M0+ at 48 MHz executes 38 CoreMark, sufficient for body-control message routing. For AEC-Q100 applications, the same die is available in the family under different temperature-grade suffixes, making this an upgrade path for automotive-grade designs.
Recommended
USB Device Peripheral
The ATSAMC20J18A-AUT integrates full-speed USB 2.0 device capability with on-chip PHY, eliminating external transceivers for HID, CDC, or vendor-class USB peripherals. The 256 KB Flash easily accommodates USB stacks plus application firmware, and the 32 KB SRAM holds USB endpoint buffers alongside protocol state machines. Operated at 48 MHz, the Cortex-M0+ core services USB polling, descriptor handling, and interrupt-driven data transfer with deterministic latency. 5V-tolerant GPIO simplifies ruggedized industrial USB dongles and POS-terminal accessories that must survive 5V bus-powered environments without protective level-shifters.
Recommended
Capacitive Touch User Interface
The ATSAMC20J18A-AUT integrates Microchip's 24-channel Peripheral Touch Controller (PTC) for capacitive touch buttons, sliders, and proximity sensors, supporting wake-on-touch functionality to extend battery life in portable appliances. The Cortex-M0+ at 48 MHz handles PTC acquisition, gesture recognition, and backlight control while the touch controller autonomously wakes the MCU from sleep. The 12-bit ADC can simultaneously monitor other analog signals such as battery voltage or temperature. The 256 KB Flash fits touch-gesture libraries plus application firmware, and the 5V-tolerant GPIO drives 5V LED drivers directly.
Recommended
Battery-Powered IoT Edge Node
The ATSAMC20J18A-AUT supports multiple low-power sleep modes with sub-microamp quiescent current when peripheral clocks are gated, making it suitable for battery-powered edge nodes reporting over CAN, UART, or USB. The 32.768 kHz RTC runs from an external crystal and provides real-time wake-up scheduling. The 12-bit ADC samples environmental sensors at low duty cycle while the Cortex-M0+ core sleeps. With 256 KB Flash and 32 KB SRAM, the device fits IoT protocol stacks such as MQTT-SN or LoRaWAN plus sensor-processing algorithms. Industrial temperature grade supports outdoor enclosure operation.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMC20J18A-AUT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMC20J17A-AUT | ATSAMC20J16A-AUT | ATSAMC20J16A-MUT |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-pin TQFP (10x10 mm) | 64-pin TQFP (10x10 mm) - same | 64-pin TQFP (10x10 mm) - same | 64-pin TQFP (10x10 mm) - same |
| Core | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ | ARM Cortex-M0+ |
| Clock Speed | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Flash Memory | 256 KB | 128 KB (-50%) | 64 KB (-75%) | 64 KB (-75%) |
| SRAM | 32 KB | 32 KB | 16 KB (-50%) | 16 KB (-50%) |
| Operating Voltage | 2.7 V to 5.5 V (5V tolerant I/O) | 2.7 V to 5.5 V (5V tolerant) | 2.7 V to 5.5 V (5V tolerant) | 2.7 V to 5.5 V (5V tolerant) |
| CAN-FD | Yes | Yes | Yes | Yes |
Key Differentiators
- Native 5V I/O tolerance (vs ATSAMD20J18A-AU)
- Largest Flash in SAM C20 64-pin TQFP family (vs ATSAMC20J17A-AUT)
- Integrated CAN-FD controller (vs ATSAMC21J18A-ANT)
Design Notes
Decouple every VDDIO pin with a 100 nF X7R ceramic placed within 2 mm of the pad; add a single 4.7 uF bulk capacitor on VDDIN. The internal LDO regulates the core voltage from VDDIN, so VDDIN should be tied directly to the 5V (or 3.3V) rail. Estimated: at full 48 MHz activity the device draws around 15 mA active; in standby with RTC running it drops below 5 uA, enabling battery-backed designs without an external supervisor.
Keep the 32.768 kHz crystal traces on XIN32/XOUT32 short and symmetric, with a ground guard ring to minimize noise injection into the RTC oscillator. If USB is used, route the DP/DM pair as a 90-ohm differential with length matching under 2 mm and avoid splits in the reference plane. Place the SWD header (SWCLK, SWDIO, NRST, GND) on a debug-friendly board edge for programming access during bring-up.
Do not assume the SERCOM pads default to GPIO - they require explicit pin-mux configuration via the PORT and PMUX registers or your ASF/MPLAB HAL code. The PTC channels share pins with GPIO and SERCOM; selecting touch functionality disables those peripheral pins. Always issue a fresh chip-erase or bootloader-driven update when switching between bank-A and bank-B Flash to avoid a corrupted-image state.
Compliance Information
RoHS compliant (Green) per Microchip product page. AEC-Q100 qualified versions of the same die are available in the SAM C20 family under different temperature-grade suffixes (e.g., -ANT, -MNT). -AUT is industrial temperature grade (-40C to +85C), not automotive grade.
