ATSAM4S2BB-UUR - 120MHz Cortex-M4 MCU, 128KB Flash, 64-WLCSP | Microchip
MPN: ATSAM4S2BB-UUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.67 | $3.67 |
| 10 | $3.32 | $33.20 |
| 100 | $2.95 | $295.00 |
| 500 | $2.65 | $1,325.00 |
| 1,000 | $2.38 | $2,380.00 |
ATSAM4S2BB-UUR Overview
A microcontroller (MCU) is a single-chip embedded computer that integrates a processor core, memory, and peripherals on one die, forming the lowest layer of the embedded systems hierarchy (MCU -> embedded processor -> semiconductor). The SAM4S family is Microchip's (formerly Atmel) mid-range ARM-based flash MCU line, positioned for cost-sensitive applications that still need 32-bit performance and DSP capability.
Key features of the ATSAM4S2BB include the Cortex-M4 core with DSP instructions and Thumb-2 instruction set, a Memory Protection Unit (MPU), embedded Flash with ECC and Security Bit plus Lock Bits, and a supply range of 1.62 V to 3.6 V. Power consumption is approximately 180 uA/MHz class, supporting battery-operated designs.
Technically, the Cortex-M4 pipeline combined with hardware DSP instructions enables efficient fixed-point signal processing (filters, FFTs) without a separate DSP. The ECC-protected Flash improves reliability in industrial environments, and lock bits support IP protection.
Typical applications include wearable and portable devices (the 3.32 x 3.32 mm WLCSP is ideal for ultra-compact PCBs), industrial sensors and control nodes, and IoT edge devices.
Design consideration: WLCSP ball-grid packages require controlled-impedance PCB layout with via-in-pad or escape routing, so verify your fab supports 0.4 mm-pitch-class micro-BGA assembly before committing to the footprint.
This page synthesizes distributor pricing, drop-in family alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATSAM4S2BB-UUR 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 ATSAM4S2BB-UUR (same form factor and footprint) β differing in Flash Memory, Mounting Type, Package, RoHS Status, SRAM.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAM4S4BB-UUR
β Drop-Inπ Reference alternative (not in catalog)
ATSAM4S4BA-UUR
β Drop-Inβ In Stock
$3.65 / Unit
View Datasheet βATSAM4S2BA-UUR
β Drop-Inπ Reference alternative (not in catalog)
ATSAM4S2BB-MUR
β Drop-Inπ Reference alternative (not in catalog)
ATSAM4S8BB-UUR
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$3.05 / Unit
View Datasheet βATSAM4S2BB-UUR Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M4 |
| Core Size | 32-Bit |
| Maximum Clock Speed | 120 MHz |
| Flash Memory | 128 KB (128K x 8) |
| SRAM | 64 KB |
| Supply Voltage Range | 1.62 V to 3.6 V |
| Power Consumption | 180 uA/MHz class |
| DSP Instructions | Yes |
| Instruction Set | Thumb-2 |
| Memory Protection Unit | Yes (MPU) |
| Flash ECC | Yes |
| Security Features | Security Bit, Lock Bits |
| Package | 64-WLCSP (UFBGA), 3.32 x 3.32 mm |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (T&R) |
| RoHS Status | Green / RoHS compliant (per Mouser 'GREEN' marking) |
| Series | SAM4S |
ATSAM4S2BB-UUR 64-wlcsp (ufbga), 3.32 x 3.32 mm Pin Configuration Guide
Pin configuration for ATSAM4S2BB-UUR (64-wlcsp (ufbga), 3.32 x 3.32 mm package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for ATSAM4S2BB-UUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM4S2BB-UUR is suitable for 6 applications: Wearable and Portable Devices, Industrial Sensors and Control Nodes, IoT Edge Devices, Portable Medical Monitoring, Consumer Audio Accessories, Smart Home and Building Control.
Wearable and Portable Devices
The ATSAM4S2BB-UUR fits wearables because its 64-ball WLCSP package measures only 3.32 x 3.32 mm, freeing board area for batteries and sensors in rings, patches, and fitness bands. The 120 MHz Cortex-M4 with DSP instructions processes sensor fusion and filtering locally, while 128 KB Flash and 64 KB SRAM host BLE-stack companions or full applications. Its 1.62 V to 3.6 V supply accepts Li-ion stacks, and 180 uA/MHz-class consumption with low-power modes extends battery life. Designers should budget for WLCSP escape routing and use Microchip's low-power mode architecture to duty-cycle the core aggressively.
Recommended
Industrial Sensors and Control Nodes
In factory automation nodes, the ATSAM4S2BB-UUR's ECC-protected 128 KB Flash guards against bit flips in electrically noisy environments, and lock bits protect firmware IP on fielded units. The 120 MHz Cortex-M4 executes PID loops, MODBUS/UART stacks, and DSP-based vibration analysis without external accelerators. The industrial temperature grade suits control cabinets and motor-adjacent installations. The SAM4S peripheral set (UART, SPI, I2C, ADC, timers) covers typical sensor interfacing. Designers should add TVS protection on field-facing lines and use the MPU to isolate safety-critical code regions from protocol stacks.
Recommended
IoT Edge Devices
For IoT edge nodes, the ATSAM4S2BB-UUR provides local compute at 120 MHz for pre-processing sensor streams before radio transmission, reducing airtime and energy per message. The Thumb-2 instruction set keeps code density high within 128 KB Flash, and 64 KB SRAM buffers packets and TLS session state when paired with a network coprocessor. Its WLCSP footprint suits small PCB antennas and compact module layouts. Pair with Microchip's Wi-Fi or LoRa radios over SPI/UART; use the hardware DSP instructions for FFT-based anomaly detection at the edge before cloud offload.
Recommended
Portable Medical Monitoring
Battery-powered medical monitors benefit from the ATSAM4S2BB-UUR's combination of DSP capability and low power: the Cortex-M4 executes digital filtering of biopotential signals (ECG, PPG) in fixed point, while 180 uA/MHz-class consumption supports multi-day battery targets. The ECC Flash protects patient-data logging integrity, and the Memory Protection Unit supports isolated firmware partitions for regulated designs. The tiny 3.32 x 3.32 mm WLCSP enables patch-style form factors. Note that medical designs should verify the part's qualification level and plan redundant sensing for safety-critical functions, since this is an industrial-grade, not medical-certified, MCU.
Recommended
Consumer Audio Accessories
The ATSAM4S2BB-UUR's Cortex-M4 DSP instructions make it suitable for consumer audio accessories such as ANC helper processing, volume/ EQ control, and button/touch interface management alongside a dedicated Bluetooth audio SoC. The 120 MHz core runs fixed-point biquad filters comfortably, and the small WLCSP fits earbud-class PCBs. Its SPI/I2C peripherals bridge to audio codecs and power-management ICs. Designers should place the MCU's crystal away from the audio codec's analog section and use its low-power modes between processing bursts to preserve battery life in true-wireless form factors.
Recommended
Smart Home and Building Control
In smart-home nodes (lighting controllers, thermostats, access panels), the ATSAM4S2BB-UUR handles touch sensing, motor control loops, and protocol stacks within its 128 KB Flash at 120 MHz. Its 1.62 V to 3.6 V range works with mains-derived supplies, and ECC Flash plus lock bits improve field reliability and protect OEM firmware. The SAM4S timer system supports PWM dimming and triac-phase control. Its small WLCSP allows placement inside wall-plate and bulb form factors. Use the MPU to separate wireless-stack code from safety-related control logic, and follow Microchip's SAM4S low-power application notes for always-on standby targets.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM4S2BB-UUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM4S4BB-UUR | ATSAM4S4BA-UUR | ATSAM4S2BA-UUR | ATSAM4S8BB-UUR |
|---|---|---|---|---|---|
| Package | 64-WLCSP (3.32 x 3.32 mm) | 64-WLCSP - same | 64-WLCSP - same | 64-WLCSP - same | 64-WLCSP - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core / Clock | Cortex-M4, 120 MHz | Cortex-M4, 120 MHz | Cortex-M4, 120 MHz | Cortex-M4, 120 MHz | Cortex-M4, 120 MHz |
| Flash Memory | 128 KB | 256 KB | 256 KB | 128 KB | 512 KB |
| 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 | 1.62 V to 3.6 V |
| Flash ECC / Security | Yes (ECC, Security Bit, Lock Bits) | Yes | Yes | Yes | Yes |
Key Differentiators
- Lowest cost point in the 64-WLCSP SAM4S family (vs ATSAM4S4BB-UUR)
- Pin-compatible Flash upgrade path (vs ATSAM4S8BB-UUR)
- Ultra-compact 3.32 x 3.32 mm Cortex-M4 (vs ATSAM4S2BB-MUR)
Design Notes
The 64-ball WLCSP (3.32 x 3.32 mm) requires microvia PCB technology: plan for via-in-pad or dog-bone escape routing with 0.1 mm-class vias and 4-layer stackup recommended. Verify your fabricator supports the HDI capability before locking the footprint, and follow Microchip's SAM4S package outgassing and reflow profile guidance in the datasheet (60001419B). Keep the ball map pinout document (family datasheet 64-ball section) as the single source of truth for routing.
Decouple each VDD ball with 100 nF ceramic capacitors placed within 1-2 mm of the ball, plus one bulk 4.7-10 uF capacitor near the package. The 1.62 V to 3.6 V range tolerates Li-ion stacks via an LDO; Estimated: at 120 MHz active mode with roughly 180 uA/MHz-class consumption (~22 mA class), an LDO dropping 3.7 V to 3.3 V dissipates under 10 mW, negligible for thermal design but relevant for battery budgeting.
Do not confuse the U (WLCSP) and M (other package) suffixes - they are not footprint-compatible despite identical silicon, per Findchips part-attribute comparison. Also confirm Flash sizing early: 128 KB fills quickly with a full RTOS plus TLS stack; qualify the pin-compatible ATSAM4S4BB-UUR (256 KB) as a second-source option on the same PCB so a memory upgrade needs no re-layout.
Compliance Information
Mouser listing describes the part as GREEN, industrial temperature, MRL B, T&R, indicating RoHS-compliant lead-free green packaging. Formal REACH and conflict-minerals declarations should be requested from Microchip for the exact ordering code.
