ATSAM4LC4AA-MU - 48MHz Cortex-M4 MCU 256KB Flash | Microchip
MPN: ATSAM4LC4AA-MU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.97 | $5.97 |
| 10 | $5.55 | $55.50 |
| 100 | $5.15 | $515.00 |
| 500 | $4.8 | $2,400.00 |
| 1,000 | $4.45 | $4,450.00 |
ATSAM4LC4AA-MU Overview
A microcontroller unit (MCU) is a single integrated circuit that combines a processor core, memory, and programmable peripherals into one chip, forming the lowest tier of the embedded-computing hierarchy: MCU -> embedded processor -> system-on-chip -> embedded system. The ATSAM4LC4AA-MU belongs to the low-power SAM4L family of ARM Cortex-M4 microcontrollers, which targets battery-powered and energy-conscious designs.
Key features include the 48 MHz ARM Cortex-M4 core with a 32-bit RISC architecture, 256KB (256K x 8) of flash program memory for code and data storage, and 32KB of SRAM for runtime variables and buffers. The SAM4L series integrates peripherals such as segment LCD controllers, hardware capacitive touch (QTouch), USB device and embedded host, 128-bit AES encryption, and audio interfaces, plus high-speed serial peripherals including USART, SPI, and I2C, according to the Atmel SAM4L datasheet summary.
Technically, the Peripheral Event System and SleepWalking features allow peripherals to communicate directly with each other and wake selectively from low-power sleep states without CPU intervention, a hallmark of the SAM4L low-power design philosophy. Industrial temperature rating supports operation in harsh environments.
Typical applications include battery-powered sensor nodes, consumer and industrial devices with segment LCD displays, capacitive-touch control panels, and secure connected devices leveraging the embedded AES engine.
A key design consideration is that this member of the family carries 256KB flash and 32KB SRAM; if code size grows, the pin-compatible denser variants within the SAM4L family should be evaluated at board design time.
This page synthesizes distributor pricing, drop-in alternatives, comparison data, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATSAM4LC4AA-MU 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 ATSAM4LC4AA-MU (same form factor and footprint) β differing in Core Processor, Package, Connectivity, Flash Memory, Max Clock Speed.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAM4LC4CA-MU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAM4LC2AA-MU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAM4LC4AA-AUR
β Drop-Inπ Reference alternative (not in catalog)
ATSAM4LC4AA-MU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M4 |
| Core Size | 32-Bit |
| Max Clock Speed | 48 MHz |
| Flash Memory | 256KB (256K x 8) |
| SRAM | 32KB |
| Series | SAM4L |
| Number of Pins | 48 |
| Package | 48-QFN (7x7 mm) exposed pad |
| Mounting Type | Surface Mount |
| Connectivity | USB device/embedded host, USART, SPI, I2C |
| Security | 128-bit AES hardware encryption |
| Touch Sensing | Embedded hardware capacitive touch (QTouch) |
| Display Peripheral | Segment LCD controller |
| Low-Power Features | Peripheral Event System, SleepWalking |
| Packaging | Tray |
ATSAM4LC4AA-MU 48-qfn (7x7 mm) exposed pad Pin Configuration Guide
Pin configuration for ATSAM4LC4AA-MU (48-qfn (7x7 mm) exposed pad 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 ATSAM4LC4AA-MU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM4LC4AA-MU is suitable for 6 applications: Battery-Powered LCD Metering Devices, Capacitive Touch Control Panels, Secure Connected Sensor Nodes, Industrial Automation Peripherals, Consumer Audio and USB Accessories, Handheld and Portable Instruments.
Battery-Powered LCD Metering Devices
Utility meters, energy monitors, and industrial gauges need years of battery life plus a readable segment LCD. The ATSAM4LC4AA-MU fits this exactly: its SAM4L low-power architecture combines a segment LCD controller with the SleepWalking mechanism, so the CPU can remain in deep sleep while peripherals autonomously sample and update the display via the Peripheral Event System, waking the 48 MHz Cortex-M4 core only when computation is required. The integrated LCD driver removes an external LCD controller IC, cutting BOM cost and board area in the 7x7 mm 48-QFN footprint. Design trade-off: the segment LCD drive is fixed-function (segments, not pixels), so applications needing graphics should move up the SAM4L or SAM D/E families.
Recommended
Capacitive Touch Control Panels
Home-appliance and industrial control panels benefit from the ATSAM4LC4AA-MU because hardware QTouch capacitive-touch sensing is embedded in the SAM4L die rather than emulated in software. The dedicated touch peripheral acquires channel measurements autonomously and can signal the Cortex-M4 core only on detected touches through the Peripheral Event System, keeping average power low in always-on panel applications. With 256KB flash, there is ample room for touch tuning tables, a USB or UART host interface, and application logic side by side. Layout-wise, touch traces should be routed away from the USB differential pair on the QFN breakout to preserve sensitivity and signal integrity.
Recommended
Secure Connected Sensor Nodes
IoT sensor nodes that transmit over USB or serial links to a gateway need authentication and data confidentiality. The ATSAM4LC4AA-MU includes a 128-bit AES hardware engine, offloading encryption from the CPU so the 48 MHz Cortex-M4 spends cycles on application logic rather than cryptography software loops. USB device mode lets the node connect directly to hosts, while USART/SPI/I2C link to radios and sensors. The 32KB SRAM comfortably buffers sensor frames and crypto state. SleepWalking allows periodic wake-sample-transmit duty cycles that stretch battery life in field-deployed nodes. Evaluate key-management requirements early, since the AES engine handles symmetric encryption but asymmetric authentication must run in software.
Recommended
Industrial Automation Peripherals
Factory sensors, actuators, and operator interfaces demand industrial temperature tolerance and robust serial connectivity, both of which the ATSAM4LC4AA-MU provides: industrial temperature grade per distributor data, plus multiple USART, SPI, and I2C peripherals for PLC backplanes and sensor buses. The 48 MHz Cortex-M4 core with hardware multiplier handles PID loops and protocol parsing (Modbus-style UART framing) with margin, while 256KB flash stores firmware plus multiple configuration sets. The exposed-pad 48-QFN package conducts heat to the PCB, supporting reliable operation near cabinet temperature extremes when the thermal pad is well soldered to a ground pour.
Recommended
Consumer Audio and USB Accessories
The SAM4L series integrates audio interfaces and a USB device/embedded host controller, making the ATSAM4LC4AA-MU a fit for USB-connected consumer accessories such as control heads, small display modules, and interface pods. USB device mode enumerates directly to PCs and phones-with-OTG, while the embedded-host mode can read USB flash media without an external host controller. The 48 MHz Cortex-M4 processes USB interrupt traffic and audio-format framing with headroom, and the segment LCD can show status or track metadata at negligible power. Firmware size for a USB class stack plus LCD logic fits comfortably in 256KB flash.
Recommended
Handheld and Portable Instruments
Portable test and measurement tools, medical monitors, and handheld scanners combine battery operation, a display, and responsive user interaction. The ATSAM4LC4AA-MU addresses all three: SleepWalking keeps standby current low between measurements, the segment LCD controller drives the display without a dedicated driver IC, and hardware QTouch supports button-free sealed enclosures important for cleaning in medical contexts. The 32-bit Cortex-M4 core performs signal math such as RMS or threshold detection at 48 MHz, and the 128-bit AES engine protects stored patient or calibration data. Its 7x7 mm QFN keeps the PCB small enough for pen-style form factors.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM4LC4AA-MU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM4LC4CA-MU | ATSAM4LC2AA-MU | ATSAM4LC4AA-AUR |
|---|---|---|---|---|
| Package | 48-QFN (7x7 mm) exposed pad | 48-QFN (7x7 mm) exposed pad - same | 48-QFN (7x7 mm) exposed pad - same | 48-QFN (7x7 mm) exposed pad - same |
| Brand | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) |
| Core | ARM Cortex-M4, 48 MHz, 32-bit | ARM Cortex-M4, 48 MHz, 32-bit | ARM Cortex-M4, 48 MHz, 32-bit | ARM Cortex-M4, 48 MHz, 32-bit |
| Flash Memory | 256KB | 512KB | 128KB | 256KB |
| SRAM | 32KB | 64KB | 16KB | 32KB |
| USB Device/Host | Yes | Yes | Yes | Yes |
| AES Security | 128-bit AES | 128-bit AES | 128-bit AES | 128-bit AES |
Key Differentiators
- Balanced 256KB/32KB memory configuration at lowest family cost-per-need (vs ATSAM4LC4CA-MU)
- SleepWalking autonomous peripheral operation (vs ATSAM4LC2AA-MU)
- Industrial-grade standard part for broad availability (vs ATSAM4LC4AA-AUR)
Design Notes
The 48-QFN (7x7 mm) package has an exposed pad on the underside that serves as the main ground and thermal path. Design the PCB land pattern with a matching center thermal via array (typ. 4-9 vias) connected to a solid ground plane, and verify solder paste segmentation on the pad to avoid voiding and floating of the QFN body during reflow. Follow the Microchip SAM4L hardware design guidelines for stencil aperture ratio on no-lead packages.
Decouple each VDD pin of the ATSAM4LC4AA-MU with 100 nF ceramic capacitors placed within 2 mm of the pin, plus one bulk capacitor (4.7-10 uF) near the supply entry. SAM4L low-power operation depends on clean supplies - place the part into its low-power sleep modes only after confirming that brown-out and supply-ramp behavior meet the datasheet startup requirements, since SleepWalking wake timing can expose marginal supply designs.
Plan memory headroom before locking the BOM: 256KB flash and 32KB SRAM are generous for LCD + touch + USB stacks, but adding TLS-style crypto or OTA update staging can overflow. Because ATSAM4LC4CA-MU (512KB) is pin-compatible, you can footprint the board for it and select the exact density at final test - a common strategy to hedge against firmware growth without respinning the PCB.
Compliance Information
Mouser listing describes the part as GREEN (halogen-free/lead-free) industrial temperature with MRL A rating. Formal RoHS/REACH certificates should be requested from Microchip.
