ATSAM4CMS4CB-AUR - Dual Cortex-M4 120MHz MCU | Microchip
MPN: ATSAM4CMS4CB-AUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.9 | $6.90 |
| 10 | $6.25 | $62.50 |
| 100 | $5.55 | $555.00 |
| 500 | $5.05 | $2,525.00 |
| 1,000 | $4.6 | $4,600.00 |
ATSAM4CMS4CB-AUR Overview
A microcontroller (MCU) is a single-chip computer that integrates a processor core, program memory, data memory, and peripherals onto one die, sitting at the device level of the embedded-systems hierarchy (MCU -> SoC -> embedded system). The SAM4CM family extends Atmel/Microchip's SAM4C family of ARM Cortex-M4 microcontrollers, purpose-built for smart energy metering where computation, communication, and security must coexist on one chip.
Key features include a unique dual-core ARM Cortex-M4/M4F architecture with FPU that lets metrology signal processing run independently from communications and application firmware, metrology-grade front-end support for residential and single-phase metering at up to class 0.2 accuracy over a 3000:1 dynamic range, and hardware cryptographic acceleration for smart-grid security. Connectivity peripherals include EBI/EMI, I2C, IrDA, SPI, and UART/USART, and the EBI/EMI interface allows extension of program and data memory via parallel memories.
Technically, the dual-core partitioning enables the metering engine to sample and compute energy quantities with deterministic timing while the second core handles protocols such as DLMS/COSEM and wireless communication, without mutual interference. The Cortex-M4F hardware FPU accelerates FFT and RMS calculations essential to metrology.
Typical applications include single-phase residential electricity meters, industrial sub-metering, smart-grid gateways, and secure data concentrators.
Design consideration: because the device targets metrology accuracy, PCB layout must separate the analog front-end ground from switching noise sources, and the flash size (256 KB) should be checked against combined application plus bootloader footprint.
This page synthesizes distributor pricing, drop-in family alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATSAM4CMS4CB-AUR 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 ATSAM4CMS4CB-AUR (same form factor and footprint) β differing in Packaging, Temperature Grade, RoHS Status, Core, Core Processor.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAM4CMS4CB-AU
β Drop-Inβ In Stock
Contact for price
View Datasheet βATSAM4C8CB-AU
β Drop-Inπ Reference alternative (not in catalog)
ATSAM4C16CB-AU
β Drop-Inβ In Stock
$5.85 / Unit
View Datasheet βATSAM4CMS4CB-AUR Maximum Ratings & Electrical Characteristics
| Core | 32-bit Dual-Core ARM Cortex-M4/M4F |
| Core Frequency | 120 MHz |
| Flash Program Memory | 256 KB (256K x 8) |
| RAM | 128 KB |
| Connectivity Interfaces | EBI/EMI, I2C, IrDA, SPI, UART/USART |
| Metrology Accuracy | Up to Class 0.2 (single-phase metering) |
| Dynamic Range | 3000:1 |
| Security | Hardware cryptographic acceleration |
| Package | 100-LQFP (14x14 mm) |
| Mounting Type | Surface Mount |
| Terminal Form | Gull Wing |
| Temperature Grade | Industrial |
| Packaging | Tape & Reel (AUR suffix) |
| RoHS Status | Compliant |
ATSAM4CMS4CB-AUR 100-lqfp (14x14 mm) Pin Configuration Guide
Pin configuration for ATSAM4CMS4CB-AUR (100-lqfp (14x14 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 ATSAM4CMS4CB-AUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM4CMS4CB-AUR is suitable for 6 applications: Single-Phase Residential Electricity Meters, Industrial Sub-Metering and Panel Meters, Smart Grid Data Concentrators, Secure AMI Metering Infrastructure, Energy Monitoring Gateways and IoT Meters, Motor and Load Monitoring in Building Automation.
Single-Phase Residential Electricity Meters
The ATSAM4CMS4CB-AUR was designed by Microchip specifically for residential and single-phase metering, achieving class 0.2 metrology accuracy over a 3000:1 dynamic range - a direct fit for utility-grade billing meters. One Cortex-M4F core executes the metrology sampling loop and energy computation with FPU-accelerated RMS and power calculations, while the second core runs the DLMS/COSEM protocol stack and UART/USART or SPI-based communications to the meter display and data concentrator. This partitioning guarantees deterministic metering timing even under heavy communication load. The 100-LQFP 14x14 mm package supports two-sided meter PCBs, and the industrial temperature grade matches outdoor meter enclosures.
Recommended
Industrial Sub-Metering and Panel Meters
In industrial sub-metering, panel builders need billing-class accuracy measurement in compact housings, and the ATSAM4CMS4CB-AUR delivers class 0.2 accuracy over a 3000:1 dynamic range that covers both lightly loaded standby circuits and heavily loaded feeders. The dual-core architecture splits metrology computation from Modbus or proprietary RS-485 links handled via its UART/USART peripherals, so measurement integrity is preserved during polling storms. Hardware cryptographic acceleration protects prepaid-metering and tenant-billing data. The 256 KB FLASH accommodates the metrology engine plus a compact protocol stack, and the EBI/EMI interface allows external flash for logging of interval data when required by utility programs.
Recommended
Smart Grid Data Concentrators
Data concentrators aggregate readings from many meters and relay them over wide-area networks, requiring both computation throughput and secure communications - strengths of the ATSAM4CMS4CB-AUR. Its 120 MHz dual-core Cortex-M4 handles protocol translation and buffer management concurrently, while the integrated CRYPTO accelerator authenticates upstream sessions and secures collected metering payloads. The EBI/EMI external bus interface attaches parallel SRAM/flash to buffer large message queues, and multiple UART/USART channels serve local meter buses. Choosing the flash-denser ATSAM4C16CB-AU sibling is common when concentrator firmware includes multiple protocol stacks; the shared 100-LQFP footprint keeps PCBs common across product tiers.
Recommended
Secure AMI Metering Infrastructure
Advanced Metering Infrastructure (AMI) deployments demand tamper-resistant billing data, and the ATSAM4CMS4CB-AUR addresses this with its hardware cryptographic accelerator plus dual-core firmware partitioning, where security-critical metrology code runs isolated from the exposed communication stack. The 128 KB RAM allows generous key handling and session buffers, and the class 0.2 / 3000:1 dynamic-range metrology ensures measurements remain trustworthy at the source rather than being corrected downstream. Industrial temperature rating suits pole-mounted and pedestal installations. The I2C and SPI buses interface tamper switches and secure element peripherals, rounding out a defense-in-depth architecture for utility-grade devices.
Recommended
Energy Monitoring Gateways and IoT Meters
IoT energy gateways benefit from the ATSAM4CMS4CB-AUR's combination of 120 MHz dual-core processing, rich connectivity (I2C, SPI, UART/USART, IrDA), and hardware crypto, enabling local analytics at the edge before data upload. One core runs sampling and aggregation while the other manages uplink firmware, and the FPU accelerates power-quality computations such as harmonics. The EBI/EMI bus extends memory for local buffering during network outages. The 100-LQFP package is available from stock at DigiKey (ships today as of 2026-09-20), simplifying prototyping, and the shared SAM4C footprint lets gateway SKUs migrate to 512 KB or 1 MB flash variants without PCB respins as feature sets grow.
Recommended
Motor and Load Monitoring in Building Automation
Building automation systems increasingly embed per-circuit energy metering, and the ATSAM4CMS4CB-AUR's metrology-grade sampling engine measures voltage, current, and power with class 0.2 accuracy over a 3000:1 dynamic range - sufficient to capture both standby loads of a few watts and HVAC loads of several kilowatts on the same channel. The dual Cortex-M4 cores split the measurement task from BACnet/Modbus communications over USART links, and the hardware FPU computes RMS and power factors efficiently. The 100-LQFP 14x14 mm industrial-grade package fits DIN-rail and panel-mounted monitoring boards, while the EBI/EMI interface supports external memory for long-interval trend logging demanded by energy dashboards.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM4CMS4CB-AUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM4CMS4CB-AU | ATSAM4C8CB-AU | ATSAM4C16CB-AU |
|---|---|---|---|---|
| Package | 100-LQFP (14x14) | 100-LQFP (14x14) - same | 100-LQFP (14x14) - same | 100-LQFP (14x14) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | Dual-Core ARM Cortex-M4/M4F, 120 MHz | Dual-Core ARM Cortex-M4/M4F, 120 MHz | ARM Cortex-M4, 120 MHz | ARM Cortex-M4, 120 MHz |
| FLASH Program Memory | 256 KB | 256 KB | 512 KB | 1024 KB |
| Packaging / Supply Form | Tape & Reel (AUR) | Tray (AU) | Tray (AU) | Tray (AU) |
Key Differentiators
- Dedicated metrology front-end with class 0.2 accuracy (vs ATSAM4C8CB-AU)
- Dual-core isolation of metrology and communications (vs ATSAM4C8CB-AU)
- Cost-optimized flash density for metering firmware (vs ATSAM4C16CB-AU)
Design Notes
For metrology class 0.2 accuracy, partition the PCB into analog front-end, digital, and power domains. Route the metering sampling lines away from switching regulators and UART/SPI buses; use a single-point star ground connecting analog and digital returns at the ADC reference. The 100-LQFP 14x14 mm footprint permits generous guard traces around the voltage and current channels. Decouple each VDD pin with 100 nF ceramic capacitors placed within 2 mm of the pin, plus one bulk 10 uF per power domain.
Plan the 256 KB FLASH budget early: the combined metrology engine, security/crypto stack, and communication protocol (DLMS/COSEM or proprietary) can approach the limit. If firmware growth is expected, design the PCB around the common SAM4C 100-LQFP footprint and qualify the ATSAM4C8CB-AU (512 KB) or ATSAM4C16CB-AU as the second source - pin-compatible family migration avoids respins. Verify dual-core firmware partitioning does not race on shared RAM regions; use the family inter-core communication primitives.
Estimated: a 120 MHz dual-core Cortex-M4 typically draws on the order of tens of milliamps at nominal supply; confirm exact figures in the SAM4CM datasheet power section before sizing the meter's power supply, since metering products are often powered from the measured line with very tight budgets. Use the device low-power modes for the communication core between polling intervals while keeping the metrology core sampling continuously - this asymmetry is precisely what the dual-core architecture enables.
The EBI/EMI external bus can run at significant parallel-bus speeds when extending program or data memory. Keep address/data lines length-matched within a few centimeters, add series termination resistors (22-33 ohm) on fast edges to limit ringing, and route the external memory bus away from the metrology analog front-end to prevent coupled noise from degrading the 3000:1 dynamic-range measurement floor.
Compliance Information
RoHS compliance indicated by DigiKey listing for ATSAM4CMS4CB-AUR. Industrial temperature grade per distributor data. REACH and halogen-free status not stated in provided data.