ATSAM4LS8BA-UUR - Cortex-M4 48MHz 512KB Flash WLCSP-64 | Microchip
MPN: ATSAM4LS8BA-UUR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.52 | $2.52 |
| 10 | $2.4 | $24.00 |
| 100 | $2.27 | $227.00 |
| 500 | $2.15 | $1,075.00 |
| 1,000 | $2.03 | $2,030.00 |
ATSAM4LS8BA-UUR Overview
A microcontroller (MCU) integrates a processor core, memory, and peripherals on a single chip, sitting at the top of the hierarchy: MCU -> embedded processor -> semiconductor device. The SAM4L family belongs to Microchip's (formerly Atmel's) ARM-based flash MCU portfolio, targeting ultra-low-power embedded systems that still require 32-bit DSP-class performance from the Cortex-M4 core.
Key features include the lowest active-mode consumption in its class (90 uA/MHz per the manufacturer product page), 1.5 uA sleep-mode current, and wake-up times down to 1.5 us - the shortest among Cortex-M4 devices at introduction. The chip integrates a USB device controller, a peripheral event system that lets peripherals communicate without CPU intervention, and the SleepWalking feature that allows peripherals to operate while the CPU core is asleep, dramatically reducing average power in duty-cycled systems.
Technically, the SAM4L uses the ARM Cortex-M4 RISC architecture with single-cycle multiply and hardware divide, a multi-layer bus matrix, and flexible supply operation around 1.8V to 3.3V (FindIC lists 1.8V/2V/2.3V/3.3V nominal rails). The 512KB Flash supports in-system programming, and industrial temperature grade operation (-40C to +85C) suits harsh environments.
Typical applications include battery-powered wearable and portable devices, sensor nodes and IoT endpoints, low-power data loggers, and space-constrained medical monitoring products where the 4.31 x 4.43 mm WLCSP-64 footprint and low sleep current are decisive.
Design consideration: WLCSP packages require precise PCB land-pattern design and solder-mask-defined pads; verify the manufacturer's ball-map document before layout and budget rework difficulty accordingly.
This page adds value beyond the datasheet by consolidating verified distributor pricing, drop-in alternative analysis within the SAM4L family, design notes, and AEO-optimized answers to common engineering questions.
Drop-in alternatives for ATSAM4LS8BA-UUR — 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 ATSAM4LS8BA-UUR (same form factor and footprint) — differing in Core Size, Package, Packaging, ADC Resolution, Flash Memory.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAM4LC8BA-UUR
✅ Drop-In✓ In Stock
$3.95 / Unit
View Datasheet →ATSAM4LS8BA-UUR Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M4 |
| Core Size | 32-Bit Single-Core |
| Maximum Clock Frequency | 48 MHz |
| Flash Memory | 512KB (512K x 8) |
| Supply Voltage (Nominal) | 1.8V / 2V / 2.3V / 3.3V |
| Package | 64-WLCSP (4.31 x 4.43 mm) |
| Mounting Type | Surface Mount |
| Peripherals | USB device, peripheral event system, SleepWalking |
| Active Mode Current | 90 uA/MHz |
| Sleep Mode Current | 1.5 uA |
| Wake-up Time | Down to 1.5 us |
| Packaging | Tape & Reel (T/R) |
ATSAM4LS8BA-UUR 64-wlcsp (4.31 x 4.43 mm) Pin Configuration Guide
Pin configuration for ATSAM4LS8BA-UUR (64-wlcsp (4.31 x 4.43 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 ATSAM4LS8BA-UUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM4LS8BA-UUR is suitable for 6 applications: Wearable and Portable Devices, Battery-Powered IoT Sensor Nodes, Medical Monitoring Products, Low-Power Data Loggers, Industrial Sensor Interfaces, USB-Connected Embedded Products.
Wearable and Portable Devices
The ATSAM4LS8BA-UUR fits wearable electronics because it combines a 48 MHz Cortex-M4 core with 1.5 uA sleep current and a 4.31 x 4.43 mm WLCSP-64 footprint, letting designers place substantial processing in fitness bands, smart rings, and biomedical patches. The 90 uA/MHz active efficiency means burst workloads (sensor fusion, BLE stack processing) consume minimal charge, while SleepWalking peripherals continue sampling sensors with the core asleep. With 512KB Flash, a full BLE-less sensor-logging application plus OTA-updatable firmware image fits without external memory. The main trade-off is WLCSP assembly cost - it requires precision land patterns and reflow profiling that hand assembly cannot achieve.
Recommended
Battery-Powered IoT Sensor Nodes
For IoT endpoints that wake, sample, transmit, and sleep, the SAM4L's wake-up time of down to 1.5 us minimizes the energy cost of frequent duty cycling - the dominant energy drain in such systems. The peripheral event system routes ADC results or timer events to peripherals without waking the Cortex-M4 core, so a node can filter and threshold sensor data at microampere levels. The USB device controller simplifies factory configuration and field diagnostics without adding a second interface chip. Designers should pair the MCU with a low-quiescent-current LDO or buck converter and budget the 1.8V/3.3V rail tolerance across battery discharge curves for the full cell life.
Recommended
Medical Monitoring Products
Portable medical monitors - pulse oximeters, ECG patch recorders, glucose loggers - benefit from the ATSAM4LS8BA-UUR's combination of DSP-class Cortex-M4 arithmetic (single-cycle MAC) for filtering algorithms and microampere sleep currents that enable multi-day to multi-week battery life. The 512KB Flash stores calibration tables, patient logs, and firmware with headroom for updates. Industrial temperature operation and the tiny WLCSP die allow integration directly on flexible or rigid-flex PCBs inside patch form factors. Compliance teams should verify the manufacturer's medical-grade quality documentation and plan for supply continuity given the single-distributor availability of this WLCSP ordering code.
Recommended
Low-Power Data Loggers
Standalone data loggers for cold chain, environmental, and asset tracking spend most of their life asleep; the SAM4L's 1.5 uA sleep current and SleepWalking timers let the RTC and ADC operate autonomously, waking the 48 MHz Cortex-M4 only when thresholds are crossed. 512KB Flash can buffer thousands of timestamped records internally, reducing writes to external memory - or the device can stream via USB to a host for extraction. The 1.5 us wake-up keeps event capture latency negligible for transient signals. Designers should size a decoupling network per the datasheet and reserve a debug UART/SWD footprint despite the small WLCSP ball-out.
Recommended
Industrial Sensor Interfaces
In industrial condition-monitoring nodes measuring vibration, temperature, or current, the Cortex-M4 core executes FFT and RMS computations locally, and the peripheral event system chains ADC sampling to DMA-class transfers without CPU intervention, keeping average consumption low even in continuously powered installations. The industrial temperature grade and 3.3V supply compatibility suit 24V systems with a local regulator. The WLCSP-64 package saves board area on dense sensor boards; if reflow capability is limited, the same silicon is offered in QFP packages within the SAM4L family. Confirm GPIO count and peripheral mapping against the datasheet ball map early in design.
Recommended
USB-Connected Embedded Products
The integrated USB device controller lets the ATSAM4LS8BA-UUR enumerate as a HID, CDC, or mass-storage device without an external USB interface chip - valuable for compact dongles, calibration tools, and programming pods. USB sessions are naturally bursty, so the 90 uA/MHz active efficiency and fast wake-up keep idle current near the 1.5 uA floor between transactions, which matters for bus-powered designs where suspend current is budgeted in microamps. The 4.31 x 4.43 mm WLCSP footprint fits USB-stick-sized PCBs. Firmware must implement suspend/resume handling correctly to realize the low-power benefit in certified USB products.
Recommended
Engineering reference data for ATSAM4LS8BA-UUR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM4LC8BA-UUR |
|---|---|---|
| Package | 64-WLCSP (4.31 x 4.43 mm) | 64-WLCSP - same footprint |
| Brand | Microchip Technology | Microchip Technology |
| Core | ARM Cortex-M4, 48 MHz | ARM Cortex-M4, 48 MHz |
| Flash Memory | 512KB | 512KB |
| Cache Controller | No | Yes (Cache Flash Controller) |
| Active Current | 90 uA/MHz | 90 uA/MHz (family figure) |
| Sleep Current | 1.5 uA | 1.5 uA (family figure) |
| USB Device | Yes | Yes |
Key Differentiators
- Lowest-power Cortex-M4 of its generation (vs Generic Cortex-M4 MCUs in larger packages)
- Extremely compact footprint (vs ATSAM4LS8BA-AUR (TFQFP-64))
- Autonomous peripheral operation (vs ATSAM4LC8BA-UUR)
Design Notes
The 64-ball WLCSP land pattern must follow Microchip's recommended drawing exactly: solder-mask-defined or non-solder-mask-defined pads per the datasheet, with aperture control to prevent bridging at the fine ball pitch. Place the package away from board edges and mounting holes - the bare die follows PCB flexure, and board bending is the leading cause of WLCSP solder-joint failure. Add an X-ray or magnified inspection step to the assembly checklist because joints under the die cannot be visually verified after reflow.
The device operates from nominal 1.8V/2V/2.3V/3.3V rails. Decouple each supply ball with low-ESR ceramics placed within a few millimeters of the ball, using via-in-pad or short escape routing given the package size. To exploit the 1.5 uA sleep current, audit every rail in the system - regulators, pull-ups, and level shifters often leak more than the MCU itself. Estimated: a 200 mAh cell powering a node that sleeps 99% of the time at 1.5 uA plus 5 uA of system leakage loses roughly 32 uAh/day, yielding years of shelf life.
Supply continuity is a project risk: Octopart reports only one primary stocking distributor for this exact WLCSP ordering code. Qualify the ATSAM4LC8BA-UUR (same package, same flash, cache-equipped) as a second source during initial design rather than after a shortage. Also verify the ball map revision - SAM4L datasheets cover multiple packages, and copying a QFP pinout into a WLCSP layout is a classic, expensive error. Budget programming/debug access (SWD) on two balls during layout; retrofitting is impossible under a WLCSP.
Compliance Information
Compliance attributes were not stated in the verified web data retrieved for this part; verify on the official Microchip product page or distributor compliance documentation.
