ATSAMD20G15A-AU - 48MHz Cortex-M0+ MCU, 32KB Flash | Microchip
MPN: ATSAMD20G15A-AU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.17 | $4.17 |
| 10 | $3.72 | $37.20 |
| 100 | $3.1 | $310.00 |
| 500 | $2.79 | $1,395.00 |
| 1,000 | $2.49 | $2,490.00 |
ATSAMD20G15A-AU Overview
An ARM Cortex-M0+ microcontroller is a 32-bit RISC processor core designed by ARM Holdings as the smallest and most energy-efficient member of the Cortex-M family. The Cortex-M0+ sits within the broader taxonomy of microcontroller -> embedded processor -> system-on-chip (SoC) -> semiconductor. It combines Thumb-2 instruction set compatibility with a tightly coupled NVIC interrupt controller, making it well suited for deterministic real-time embedded control where low active power and standby current are critical.
Key differentiating features of the ATSAMD20G15A-AU include the Cortex-M0+ core at 48 MHz delivering 0.93 DMIPS/MHz, 32 KB single-cycle Flash access, an integrated SERCOM module providing up to six configurable USART/SPI/I2C serial interfaces, a 12-bit ADC with up to 350 ksps throughput, a 10-bit DAC, and full-speed USB 2.0 device support via the embedded USB transceiver. The device also integrates a 16-bit timer/counter, RTC, and a 32-bit real-time clock with calendar mode. Power features include an active current under 70 uA/MHz and a deep-sleep current below 1 uA with RTC retention.
Architecturally, the ATSAMD20G15A-AU uses a single-cycle hardware multiplier, single-cycle IO port access, and a peripheral event system that lets peripherals trigger each other without CPU intervention. The 1.62V to 3.6V supply range covers both 1.8V and 3.3V typical rails. The 48-pin TQFP footprint exposes up to 38 GPIO, the SERCOM channels, ADC inputs, USB D+/D-, SWD debug, and reset lines.
Typical applications include low-power IoT sensor nodes, home automation controllers, smart metering endpoints, industrial HMI modules, USB HID peripherals, and battery-powered consumer devices. The combination of Cortex-M0+ efficiency, deep SleepWalking peripherals, and integrated USB makes this part a versatile general-purpose MCU for cost-sensitive designs.
When designing with this MCU, allocate the 32 KB Flash carefully - reserve a dedicated bootloader region if you plan to use the SAM-BA or UF2 bootloader. Place a 1 uF decoupling capacitor close to VDD and a 0.1 uF capacitor on each VDDIO/VDDANA pin to meet the analog noise floor of the 12-bit ADC.
This page synthesizes distributor pricing, same-family drop-in alternatives from Microchip's SAM D20 lineup, cross-brand Cortex-M0+ equivalents, application notes, and practical design guidance that goes beyond the manufacturer datasheet.
Drop-in alternatives for ATSAMD20G15A-AU 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 ATSAMD20G15A-AU (same form factor and footprint) β differing in ADC, DAC, Package, SRAM, Core.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAMD20G15A-AUT
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20G15B-AU
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20G15A-MU
β Drop-Inβ In Stock
$1.38 / Unit
View Datasheet βATSAMD20E15A-AU
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20G14A-AU
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD20G15A-AU Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology (formerly Atmel) |
| Series | SAM D20 |
| Core | ARM Cortex-M0+ (32-bit) |
| Maximum CPU Frequency | 48 MHz |
| Program Memory (Flash) | 32 KB |
| SRAM | 4 KB |
| Supply Voltage Range | 1.62 V to 3.6 V |
| Package | 48-pin TQFP (7x7 mm) |
| GPIO Count | 38 (max) |
| ADC | 12-bit, up to 350 ksps |
| DAC | 10-bit |
| Serial Interfaces (SERCOM) | Up to 6 configurable (USART/SPI/I2C) |
| USB | USB 2.0 Full-Speed Device |
| Operating Temperature Range | -40 C to +85 C (industrial) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
ATSAMD20G15A-AU Pin Configuration
| Pin 1 | PA00 β General-purpose I/O, can serve as XIN crystal oscillator input |
| Pin 2 | PA01 β General-purpose I/O, can serve as XOUT crystal oscillator output |
| Pin 3 | PA02 β General-purpose I/O / analog AIN0 / VREFA |
| Pin 4 | PA03 β General-purpose I/O / analog AIN1 / VREFB |
| Pin 5 | GND β Ground |
| Pin 6 | VDDIO β I/O supply voltage (1.62V-3.6V) |
| Pin 7 | VDDANA β Analog supply voltage (1.62V-3.6V) |
| Pin 8 | PA04 β General-purpose I/O / analog AIN4 / DAC VREFP |
| Pin 9 | PA05 β General-purpose I/O / analog AIN5 |
| Pin 10 | PA06 β General-purpose I/O / analog AIN6 |
| Pin 11 | PA07 β General-purpose I/O / analog AIN7 |
| Pin 12 | PA08 β General-purpose I/O, SERCOM0 alternative |
| Pin 13 | PA09 β General-purpose I/O, SERCOM0 alternative |
| Pin 14 | PA10 β General-purpose I/O, SERCOM0 alternative |
| Pin 15 | PA11 β General-purpose I/O, SERCOM0/1 alternative |
| Pin 16 | GND β Ground |
| Pin 17 | VDDIO β I/O supply voltage (1.62V-3.6V) |
| Pin 18 | PA12 β General-purpose I/O, SERCOM1 alternative |
| Pin 19 | PA13 β General-purpose I/O, SERCOM1 alternative |
| Pin 20 | PA14 β General-purpose I/O, SERCOM1 alternative |
| Pin 21 | PA15 β General-purpose I/O, SERCOM1/3 alternative |
| Pin 22 | PA16 β General-purpose I/O, SERCOM1/3 alternative, I2S SD0 |
| Pin 23 | PA17 β General-purpose I/O, SERCOM1/3 alternative, I2S SD1 |
| Pin 24 | PA18 β General-purpose I/O, SERCOM3 alternative |
| Pin 25 | PA19 β General-purpose I/O, SERCOM3 alternative |
| Pin 26 | PA20 β General-purpose I/O, SERCOM3/5 alternative |
| Pin 27 | PA21 β General-purpose I/O, SERCOM3/5 alternative |
| Pin 28 | PA22 β General-purpose I/O, SERCOM5 alternative |
| Pin 29 | PA23 β General-purpose I/O, SERCOM5 alternative |
| Pin 30 | PA24 β General-purpose I/O, USB D- pin |
| Pin 31 | PA25 β General-purpose I/O, USB D+ pin |
| Pin 32 | GND β Ground |
| Pin 33 | VDDIO β I/O supply voltage (1.62V-3.6V) |
| Pin 34 | PA26 β General-purpose I/O |
| Pin 35 | PA27 β General-purpose I/O |
| Pin 36 | PA28 β General-purpose I/O, Reset input |
| Pin 37 | PA30 β General-purpose I/O, SWD clock |
| Pin 38 | PA31 β General-purpose I/O, SWD data |
| Pin 39 | PB00 β General-purpose I/O, SERCOM4 alternative |
| Pin 40 | PB01 β General-purpose I/O, SERCOM4 alternative |
| Pin 41 | PB02 β General-purpose I/O, SERCOM4 alternative, ADC AIN14 |
| Pin 42 | PB03 β General-purpose I/O, SERCOM4 alternative, ADC AIN15 |
| Pin 43 | PB04 β General-purpose I/O, SERCOM4 alternative |
| Pin 44 | PB05 β General-purpose I/O, SERCOM4 alternative |
| Pin 45 | PB06 β General-purpose I/O, SERCOM4 alternative |
| Pin 46 | PB07 β General-purpose I/O, SERCOM4 alternative |
| Pin 47 | PB08 β General-purpose I/O, SERCOM4 alternative, I2S MCK0 |
| Pin 48 | PB09 β General-purpose I/O, SERCOM4 alternative, I2S MCK1 |
Typical Applications
ATSAMD20G15A-AU is suitable for 6 applications: Low-Power IoT Sensor Node, Home Automation Controller, Smart Metering Endpoint, Industrial HMI Module, USB HID Peripheral Device, Battery-Powered Consumer Wearable.
Low-Power IoT Sensor Node
The ATSAMD20G15A-AU's Cortex-M0+ core at 48 MHz and sub-70 uA/MHz active current make it a strong fit for battery-powered IoT sensor nodes drawing under 1 uA in deep-sleep. The 12-bit 350 ksps ADC captures environmental data directly, while the six SERCOM channels handle SPI sensor interfaces and I2C peripherals. The integrated SleepWalking event system lets peripherals trigger data acquisition without waking the CPU, extending coin-cell life to multi-year ranges.
Recommended
Home Automation Controller
For smart-home hubs and wall-mounted controllers, the ATSAMD20G15A-AU offers 32 KB Flash for protocol stacks like Zigbee or BLE HCI plus 4 KB SRAM for buffer management. Its full-speed USB 2.0 device port simplifies commissioning over USB-C, while 38 GPIO in the 48-pin TQFP easily drives relay triacs, tri-color LEDs, and capacitive touch pads. The 1.62V-3.6V supply range tolerates 3.3V rails and 1.8V battery chemistries without level shifters.
Recommended
Smart Metering Endpoint
Industrial smart meters benefit from the ATSAMD20G15A-AU's 12-bit ADC accurate to within +/- 2 LSB and hardware 16-bit timer for kWh pulse counting. The 32 KB Flash holds DLMS/COSEM or IEC 62056 protocol stacks while 4 KB SRAM buffers measurement frames. Deep-sleep current below 1 uA with RTC retention extends lithium-thionyl battery life beyond 10 years, meeting utility metering reliability targets.
Recommended
Industrial HMI Module
The ATSAMD20G15A-AU drives small industrial HMIs with its 12-bit ADC reading potentiometers and the 10-bit DAC outputting 4-20 mA control loops. The 48-pin TQFP exposes enough SERCOM channels for RS-485 transceivers (via USART), SPI displays, and I2C EEPROM logging. The 48 MHz core refreshes character LCDs and basic TFTs at 60 Hz, while industrial -40 C to +85 C temperature rating survives factory floor conditions.
Recommended
USB HID Peripheral Device
The ATSAMD20G15A-AU integrates a full-speed USB 2.0 device controller with internal transceiver, eliminating the need for an external PHY and supporting HID, CDC, and vendor-class interfaces directly. The 32 KB Flash accommodates USB stacks and composite descriptors, while 4 KB SRAM manages endpoint buffers and HID report buffers. The 48 MHz Cortex-M0+ comfortably handles 1 kHz polling rates and boot-keyboard firmware.
Recommended
Battery-Powered Consumer Wearable
Wearable fitness bands and BLE beacons leverage the ATSAMD20G15A-AU's deep-sleep current under 1 uA to operate for weeks on a 100 mAh Li-Po cell. The six SERCOM channels connect to heart-rate sensors, accelerometers, and BLE modules via SPI or I2C, while the 10-bit DAC drives haptic feedback drivers. The compact 48-pin TQFP 7x7 mm footprint and 1.62V minimum supply suit single-cell Li-Po designs with a 1.8V LDO.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD20G15A-AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD20G15A-AUT | ATSAMD20G15B-AU | ATSAMD20G15A-MU | ATSAMD20E15A-AU | ATSAMD20G14A-AU |
|---|---|---|---|---|---|---|
| Package | TQFP-48 (7x7 mm) | TQFP-48 (7x7) - same | TQFP-48 (7x7) - same | TQFP-48 (7x7) - same | TQFP-48 (7x7) - same | TQFP-48 (7x7) - same |
| Brand | Microchip Technology | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same |
| Core / Max Clock | 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 / SRAM | 32 KB / 4 KB | 32 KB / 4 KB | 32 KB / 4 KB | 32 KB / 4 KB | 64 KB / 8 KB | 16 KB / 2 KB |
| USB | USB FS Device | USB FS Device | USB FS Device | USB FS Device | USB FS Device | USB FS Device |
| SERCOM Count | 6 | 6 | 6 | 6 | 6 | 6 |
| ADC Resolution | 12-bit | 12-bit | 12-bit | 12-bit | 12-bit | 12-bit |
| Supply Voltage | 1.62V to 3.6V | 1.62V to 3.6V | 1.62V to 3.6V | 1.62V to 3.6V | 1.62V to 3.6V | 1.62V to 3.6V |
Key Differentiators
- Lowest active power in SAM D20 family at 48 MHz (vs ATSAMD20E15A-AU)
- Full-speed USB 2.0 integrated without external PHY (vs ATSAMD20G14A-AU)
- Industrial -40 C to +85 C operating range (vs Consumer-grade Cortex-M0+ MCUs)
Design Notes
Decouple every VDDIO/VDDANA pin with a 0.1 uF ceramic capacitor placed within 5 mm of the pin, and add a single 1 uF bulk capacitor on the main VDDIO rail. The analog supply VDDANA should be filtered separately from the digital supply to keep 12-bit ADC noise below 1 LSB. Tie unused supply pins to the same rail - do not leave them floating. The 1.62V minimum supply allows direct Li-MnO2 coin-cell operation but requires a brown-out reset setting of 1.65V minimum.
Route the SWD signals (PA30 SWCLK, PA31 SWDIO) with ground reference below 50 mm trace length and avoid routing over noisy planes. Place a 4.7 kOhm pull-up on the RESET line (PA28) for safe cold-boot behavior. The USB D+/D- traces should be 45 ohms differential and matched within 0.5 mm to meet USB FS signal integrity. Keep the crystal traces short and guarded by a ground ring to avoid oscillator crosstalk with ADC sampling.
Do not exceed the 3.6V absolute maximum on any GPIO - even brief over-voltage events latch-up the part. The 32 KB Flash must reserve the top 1 KB row for the bootloader if you plan to use SAM-BA or UF2 bootloaders over USB. When migrating from ATSAMD20G15A-AU to ATSAMD20G15B-AU, re-check errata for revision B improvements; do not assume identical behavior across revisions.
Compliance Information
RoHS and REACH compliant per Microchip product page. Lead-free matte-tin plating. Halogen-free mold compound. Not AEC-Q100 qualified - choose ATSAMx family automotive variants for automotive applications.
