ATSAM4S2AA-AU - Cortex-M4 120MHz MCU 128KB Flash | Microchip
MPN: ATSAM4S2AA-AU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.51 | $5.51 |
| 10 | $4.96 | $49.60 |
| 25 | $4.62 | $115.50 |
| 100 | $4.31 | $431.00 |
| 1,000 | $4.04 | $4,040.00 |
ATSAM4S2AA-AU Overview
An MCU (microcontroller unit) is a single integrated circuit that combines a processor core, memory, and peripherals into one chip, sitting at the heart of embedded systems. Within the hierarchy of computing devices, a microcontroller occupies the space between simple 8-bit controllers and full application processors, and the SAM4S family belongs to Microchip's (formerly Atmel) ARM-based 32-bit SAM portfolio, built around the ARM Cortex-M4 core with Thumb-2 instruction set, DSP instructions, and a Memory Protection Unit (MPU).
Key features of the ATSAM4S2AA include the 120 MHz Cortex-M4 with hardware DSP instructions for signal-processing workloads, 128 KB of embedded Flash with ECC, Security Bit, and Lock Bits for code protection, and 64 KB of SRAM. The supply range spans 1.62V to 3.6V, and typical power consumption is as low as 180 uA in the manufacturer's published low-power operating modes.
Technical depth comes from the SAM4S peripheral set, which historically includes high-speed USB Device, multiple USART/UART channels, SPI, TWI (I2C), PWM channels, a 12-bit ADC, and a real-time timer/clock ecosystem, allowing the device to drive industrial and consumer designs from a single chip. The Cortex-M4 core provides single-cycle MAC and hardware divide, useful for control loops and digital filtering.
Typical applications include industrial control and automation nodes, consumer devices, and embedded systems that previously used the pin-compatible SAM3S/SAM3N/SAM7S families and want a drop-in performance upgrade.
A key design consideration is supply voltage: the 1.62V to 3.6V operating range means 5V-tolerant I/O must not be assumed; use level shifting for legacy 5V signals. The LQFP-48 (7x7) footprint also offers pin-to-pin compatibility across the SAM4S/SAM3S/SAM3N/SAM7S families, simplifying PCB reuse.
This page synthesizes distributor pricing, pin-compatible family alternatives, and practical design guidance not found in the manufacturer datasheet alone.
Drop-in alternatives for ATSAM4S2AA-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 ATSAM4S2AA-AU (same form factor and footprint) β differing in Flash Memory, Operating Temperature.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAM4S4AA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$3.75 / Unit
View Datasheet βATSAM3S2AA-AU
β Drop-Inπ Reference alternative (not in catalog)
ATSAM3S4AA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAM3N4AA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAM7S64-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAM4S2AA-AU Maximum Ratings & Electrical Characteristics
| Core | ARM Cortex-M4 (32-bit) |
| Maximum Clock Frequency | 120 MHz |
| Flash Memory | 128 KB |
| SRAM | 64 KB |
| Instruction Set | Thumb-2 with DSP instructions |
| Memory Protection Unit | Yes (MPU) |
| Supply Voltage Range | 1.62 V to 3.6 V |
| Typical Low-Power Consumption | 180 uA (manufacturer published) |
| Package | 48-LQFP (7x7 mm) |
| Mounting Type | Surface Mount |
| Series | SAM4S |
| Core Width | 32-bit |
| Operating Temperature | Industrial range (GREEN, IND TEMP per distributor data) |
| Flash Features | ECC, Security Bit, Lock Bits |
| Packaging | Tray |
ATSAM4S2AA-AU Pin Configuration
| Pin 1 | PA0 β GPIO Port A bit 0 (multiplexed peripheral I/O) |
| Pin 2 | PA1 β GPIO Port A bit 1 (multiplexed peripheral I/O) |
| Pin 3 | PA2 β GPIO Port A bit 2 (multiplexed peripheral I/O) |
| Pin 4 | PA3 β GPIO Port A bit 3 (multiplexed peripheral I/O) |
| Pin 5 | PA4 β GPIO Port A bit 4 (multiplexed peripheral I/O) |
| Pin 6 | PA5 β GPIO Port A bit 5 (multiplexed peripheral I/O) |
| Pin 7 | PA6 β GPIO Port A bit 6 (multiplexed peripheral I/O) |
| Pin 8 | PA7 β GPIO Port A bit 7 (multiplexed peripheral I/O) |
| Pin 9 | PA8 β GPIO Port A bit 8 (multiplexed peripheral I/O) |
| Pin 10 | PA9 β GPIO Port A bit 9 (multiplexed peripheral I/O) |
| Pin 11 | PA10 β GPIO Port A bit 10 (multiplexed peripheral I/O) |
| Pin 12 | PA11 β GPIO Port A bit 11 (multiplexed peripheral I/O) |
| Pin 13 | PA12 β GPIO Port A bit 12 (multiplexed peripheral I/O) |
| Pin 14 | PA13 β GPIO Port A bit 13 (multiplexed peripheral I/O) |
| Pin 15 | PA14 β GPIO Port A bit 14 (multiplexed peripheral I/O) |
| Pin 16 | PA15 β GPIO Port A bit 15 (multiplexed peripheral I/O) |
| Pin 17 | PA16 β GPIO Port A bit 16 (multiplexed peripheral I/O) |
| Pin 18 | PA17 β GPIO Port A bit 17 (multiplexed peripheral I/O) |
| Pin 19 | PA18 β GPIO Port A bit 18 (multiplexed peripheral I/O) |
| Pin 20 | PA19 β GPIO Port A bit 19 (multiplexed peripheral I/O) |
| Pin 21 | PA20 β GPIO Port A bit 20 (multiplexed peripheral I/O) |
| Pin 22 | PA21 β GPIO Port A bit 21 (multiplexed peripheral I/O) |
| Pin 23 | PA22 β GPIO Port A bit 22 (multiplexed peripheral I/O) |
| Pin 24 | GND β Ground |
| Pin 25 | PB0 β GPIO Port B bit 0 (multiplexed peripheral I/O) |
| Pin 26 | PB1 β GPIO Port B bit 1 (multiplexed peripheral I/O) |
| Pin 27 | PB2 β GPIO Port B bit 2 (multiplexed peripheral I/O) |
| Pin 28 | PB3 β GPIO Port B bit 3 (multiplexed peripheral I/O) |
| Pin 29 | PB4 β GPIO Port B bit 4 (multiplexed peripheral I/O) |
| Pin 30 | PB5 β GPIO Port B bit 5 (multiplexed peripheral I/O) |
| Pin 31 | PB6 β GPIO Port B bit 6 (multiplexed peripheral I/O) |
| Pin 32 | PB7 β GPIO Port B bit 7 (multiplexed peripheral I/O) |
| Pin 33 | PB8 β GPIO Port B bit 8 (multiplexed peripheral I/O) |
| Pin 34 | PB9 β GPIO Port B bit 9 (multiplexed peripheral I/O) |
| Pin 35 | PB10 β GPIO Port B bit 10 (multiplexed peripheral I/O) |
| Pin 36 | PB11 β GPIO Port B bit 11 (multiplexed peripheral I/O) |
| Pin 37 | PB12 β GPIO Port B bit 12 (multiplexed peripheral I/O) |
| Pin 38 | PB13 β GPIO Port B bit 13 (multiplexed peripheral I/O) |
| Pin 39 | TCK/Test-related pin β JTAG/debug and test signal (see datasheet pin description) |
| Pin 40 | NRST β Bidirectional reset input/output with internal pull-up |
| Pin 41 | VDDIO β I/O power supply (1.62 V to 3.6 V) |
| Pin 42 | VDDCORE β Core power supply (via regulator output) |
| Pin 43 | VDDIN β Regulator input supply |
| Pin 44 | GND β Ground (core/analog return) |
| Pin 45 | XIN β Main crystal oscillator input |
| Pin 46 | XOUT β Main crystal oscillator output |
| Pin 47 | VDDOUT β 1.2 V regulator output (decouple to GND) |
| Pin 48 | VDDPLL β PLL power supply (filtered) |
Typical Applications
ATSAM4S2AA-AU is suitable for 6 applications: Industrial Control and Automation, Consumer Electronics, Embedded Systems Migration from SAM7S/SAM3S, Motor Control, Battery-Powered Portable Devices, IoT Sensor Nodes and Gateways.
Industrial Control and Automation
The ATSAM4S2AA-AU fits industrial control nodes because its 120 MHz Cortex-M4 core with DSP instructions handles PID loops, protocol parsing (Modbus over USART), and digital filtering that overload slower Cortex-M3 parts. With 128 KB Flash and 64 KB SRAM, it can hold a full control firmware plus communication stack, and the industrial temperature range per distributor data suits factory-floor enclosures. Its 1.62V to 3.6V supply operates from standard 3.3V industrial rails. Per the SAM4S datasheet, the peripheral set (USART, SPI, TWI, PWM) interfaces directly with PLC I/O, sensors, and motor drivers, while Flash lock bits protect proprietary control algorithms on deployed equipment.
Recommended
Consumer Electronics
In consumer devices such as small appliances, toys, and handheld gadgets, the ATSAM4S2AA-AU provides ARM Cortex-M4 performance at a sub-$6 price point (about $5.04 as of 2026-09-20 at LCSC). The 120 MHz core accelerates UI rendering, capacitive-touch scanning, and audio effects using DSP instructions, while 128 KB Flash and 64 KB SRAM are sufficient for typical consumer feature sets. The 48-pin LQFP (7x7 mm) keeps board area small for cost-sensitive layouts, and pin-to-pin compatibility with the wider SAM4S/SAM3S families lets one PCB serve multiple product tiers - populating the 128 KB part for base models and the 256 KB ATSAM4S4AA-AU for premium variants without respinning the board.
Recommended
Embedded Systems Migration from SAM7S/SAM3S
The ATSAM4S2AA-AU is the natural migration target for legacy designs built on SAM7S, SAM3S, or SAM3N microcontrollers. According to the Microchip SAM4S datasheet (60001419B), the SAM4S series offers pin-to-pin compatibility with these families, so an existing 48-LQFP PCB accepts the ATSAM4S2AA-AU without layout changes. The gain is substantial: from an ARM7TDMI at 55 MHz to a Cortex-M4 at 120 MHz with DSP instructions and an MPU, while retaining familiar Atmel/Microchip peripherals and the same software ecosystem (ASF/HAL). Typical benefit is 2-4x real-time headroom for the same firmware structure, easing addition of USB, richer communications, or control algorithms to older products.
Recommended
Motor Control
The ATSAM4S2AA-AU suits small motor-control applications - fans, pumps, and light industrial drives - because its Cortex-M4 core provides single-cycle MAC and DSP instructions at 120 MHz, enough for field-oriented control or sensored trapezoidal loops at typical PWM frequencies. The SAM4S peripheral set includes PWM timers and a 12-bit ADC for current-sense sampling, enabling closed-loop current control from a single chip. With 128 KB Flash, the full control, protection, and communication firmware fits without banking. Designers should budget ADC sampling latency and verify PWM resolution from the datasheet peripheral sections; the industrial temperature grade supports enclosed motor-driver environments operating from 3.3V logic rails.
Recommended
Battery-Powered Portable Devices
The ATSAM4S2AA-AU fits battery-powered products because Microchip publishes 180 uA-class power consumption for the SAM4S2A in low-power operating conditions, within a 1.62V to 3.6V supply window that accepts a single lithium cell via a small LDO. At 120 MHz, the Cortex-M4 completes burst workloads quickly and returns to sleep, so average current stays low; DSP instructions shorten sensor-fusion and filtering execution versus a Cortex-M0. The 48-pin LQFP (7x7 mm) balances I/O count and footprint for compact handheld boards. For deep-sleep duty-cycle designs, verify exact current figures per power mode in the SAM4S datasheet electrical characteristics and budget regulator quiescent current accordingly.
Recommended
IoT Sensor Nodes and Gateways
For IoT nodes, the ATSAM4S2AA-AU offers the connectivity peripherals (USART, SPI, TWI) needed to attach Wi-Fi, BLE, or LoRa modules over UART/SPI, while its 64 KB SRAM buffers sensor data and protocol stacks comfortably. The Cortex-M4's DSP instructions accelerate FFT-based vibration or acoustic sensing at the edge, reducing transmitted data volume. Flash security features - Security Bit and Lock Bits per the datasheet - protect firmware and credentials in the field, an important consideration for deployed IoT hardware. The 3.3V operation and industrial temperature grade support both indoor gateways and outdoor sensor enclosures; pin-to-pin SAM4S family compatibility allows Flash-size tuning per product SKU without PCB changes.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM4S2AA-AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM4S4AA-AU | ATSAM3S2AA-AU | ATSAM3N4AA-AU | ATSAM7S64-AU |
|---|---|---|---|---|---|
| Package | 48-LQFP (7x7 mm) | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core / Max Frequency | Cortex-M4, 120 MHz | Cortex-M4, 120 MHz | Cortex-M3, 64 MHz | Cortex-M3, 96 MHz | ARM7TDMI, 55 MHz |
| Flash Memory | 128 KB | 256 KB | 128 KB | 256 KB | 64 KB |
| SRAM | 64 KB | 64 KB | 32 KB | 24 KB | 16 KB |
| DSP Instructions / MPU | Yes / Yes | Yes / Yes | No / Yes | No / Yes | No / No |
| Supply Voltage | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 3.0 V to 3.6 V |
| Pin Compatibility | SAM4S/SAM3S/SAM3N/SAM7S pin-to-pin family | Drop-in compatible | Drop-in compatible | Drop-in compatible | Drop-in compatible (verify peripheral mapping) |
Key Differentiators
- Cortex-M4 with DSP instructions at 120 MHz (vs ATSAM3S2AA-AU)
- Balanced 128 KB Flash / 64 KB SRAM (vs ATSAM3N4AA-AU)
- Modern low-voltage operation with ECC Flash (vs ATSAM7S64-AU)
- Cost-optimal memory tier in a shared footprint (vs ATSAM4S4AA-AU)
Design Notes
The SAM4S2A uses an on-chip 1.2 V core regulator: VDDIN is the regulator input, VDDOUT is the 1.2 V regulator output, and VDDCORE must be connected to VDDOUT with a suitable decoupling capacitor (typically 1.1 uF to 2.2 uF per datasheet recommendations, verify exact value in the SAM4S datasheet power section). VDDPLL needs an RC filter for clean PLL supply. Do not drive VDDCORE from an external supply unless the internal regulator is configured accordingly - incorrect core supply handling is a common first-revision failure on SAM4S boards.
Decouple every VDDIO pin with 100 nF ceramic capacitors placed within 2 mm of the pin, plus one bulk 4.7 uF to 10 uF capacitor near the supply entry. The crystal (XIN/XOUT) loop should be kept short with a ground guard ring; typical main crystals are in the 4 MHz to 12 MHz range, multiplied by the PLL to 120 MHz. The NRST pin has an internal pull-up but benefits from an external 100 nF capacitor for power-on reset filtering. Per the SAM4S datasheet, pin-to-pin SAM family compatibility lets one layout serve SAM4S/SAM3S variants - keep all footprints consistent.
Three frequent pitfalls: (1) Assuming 5V-tolerant I/O - the supply range is 1.62 V to 3.6 V, so 5 V signals need level shifting. (2) Migrating firmware from SAM7S/SAM3S without updating the flash programming and clock configuration - the Cortex-M4 PLL setup differs from ARM7/SAM3N. (3) Ignoring the peripheral multiplexer: most GPIO pins serve multiple peripheral functions, so pin assignments must be cross-checked against the datasheet multiplexing tables before layout freeze. Estimated: budget roughly 30 percent Flash headroom in the 128 KB device for future OTA or feature growth, or use the drop-in 256 KB ATSAM4S4AA-AU.
Compliance Information
Distributor data (Mouser) lists the part as 'GREEN IND TEMP MRL A', corresponding to Microchip's green (RoHS-compliant, lead-free) industrial-temperature packaging. REACH, halogen-free, and conflict-minerals declarations should be confirmed on Microchip's official product page.