MC9S12XA256CAAR - 16-bit 256KB Flash MCU 80MHz | NXP
MPN: MC9S12XA256CAAR ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.2 | $162.00 |
| 100 | $13.85 | $1,385.00 |
| 500 | $11.4 | $5,700.00 |
| 1,000 | $9.95 | $9,950.00 |
MC9S12XA256CAAR Overview
An MCU (microcontroller unit) is a single-chip computer that combines a CPU core, non-volatile program memory (Flash), volatile working memory (RAM), and on-chip peripherals such as ADCs, timers, and communication interfaces. The HCS12X is a 16-bit CISC architecture MCU family used widely in automotive body, chassis, and industrial control. Within the broader taxonomy, MC9S12XA256CAAR belongs to: microcontroller -> 16-bit MCU -> HCS12X family -> automotive/industrial MCU -> embedded system.
Key features of this part include 80 MHz maximum CPU frequency, 8-channel 10-bit ADC, multiple PWM channels for motor and power control, low-voltage detection (LVD), power-on reset (POR), and a window watchdog timer (WDT). The integrated XGATE co-processor offloads interrupt-driven tasks from the main CPU, boosting real-time throughput for CAN/LIN message handling and I/O processing. Operating voltage is 2.5 V core supply.
Technical depth: the HCS12X core uses a 16-bit CISC instruction set with enhanced indexing and page-switching for >64 KB code spaces. The XGATE is an independent RISC-style peripheral co-processor that runs while the main core is halted, enabling deterministic interrupt latencies in the low microsecond range. The 80-QFP (14x14 mm) LQFP package provides ample PCB routing area and supports hand-soldering and rework, preferred for low-to-medium volume automotive ECUs.
Typical applications include automotive body controllers, CAN/LIN gateway nodes, industrial PLC I/O modules, HVAC control boards, sensor fusion front-ends, and small motor-control BLDC drivers. The combination of 256 KB Flash and the XGATE co-processor makes it a workhorse for chassis and body domain ECUs that require deterministic communication.
When designing with this part, observe the 2.5 V core supply requirement and provide adequate decoupling (>=10 uF bulk + 100 nF per VDD pin pair). The XGATE firmware must be linked into the Flash image; designers should consult the S12XD/XB/XA reference manual for the memory map and interrupt vector table before porting code.
This page synthesizes distributor pricing, lifecycle status, drop-in compatible alternatives from the HCS12X family, and practical engineering notes that are not gathered in one place on the manufacturer datasheet.
Drop-in alternatives for MC9S12XA256CAAR — 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 MC9S12XA256CAAR (same form factor and footprint) — differing in Package, Core Processor, Operating Temperature, Supply Voltage, ADC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9S12XA256CAA
✅ Drop-In✓ In Stock
$10.5 / Unit
View Datasheet →MC9S12XDT256VAA
✅ Drop-In✓ In Stock
$9.05 / Unit
View Datasheet →MC9S12XD256MAA
✅ Drop-In✓ In Stock
$11.95 / Unit
View Datasheet →MC9S12XDG128CAA
✅ Drop-In📋 Reference alternative (not in catalog)
MC9S12XEG128MAA
✅ Drop-In✓ In Stock
$8.9 / Unit
View Datasheet →MC9S12XA256CAAR Maximum Ratings & Electrical Characteristics
| Core Processor | HCS12X |
| Core Size | 16-Bit |
| Maximum CPU Frequency | 80 MHz |
| Program Memory Size | 256 KB (256K x 8) Flash |
| RAM Size | 16 KB |
| EEPROM Size | 4 KB |
| Number of I/O | 59 |
| Package | 80-LQFP (14x14 mm) |
| Mounting Type | Surface Mount |
| Connectivity | EBI/EMI, I2C, IrDA, LINbus, SCI, SPI |
| Peripherals | LVD, POR, PWM, WDT |
| ADC | 8-channel 10-bit |
| Co-Processor | XGATE |
| Supply Voltage | 2.5 V |
| RoHS Status | Compliant |
| Part Status | Obsolete |
| Series | HCS12X |
MC9S12XA256CAAR 80-lqfp (14x14 mm) Pin Configuration Guide
Pin configuration for MC9S12XA256CAAR (80-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 MC9S12XA256CAAR.
Refer to the datasheet for full pin configuration.
Typical Applications
MC9S12XA256CAAR is suitable for 6 applications: Automotive Body Control Module (BCM), CAN/LIN Gateway Node, HVAC Control Board, Industrial PLC I/O Module, Small BLDC Motor Controller, Sensor Fusion Front-End.
Automotive Body Control Module (BCM)
The MC9S12XA256CAAR is well matched to automotive body controllers because its 256 KB Flash holds BCM application firmware including door/window/lock logic, lighting sequencing, and RKE handling, while the XGATE co-processor offloads CAN/LIN message processing so the main CPU can service timing-critical tasks. With 59 GPIO, the part can drive LEDs, read switch inputs, and interface to multiple LIN slaves directly. The 80-LQFP package is automotive-proven and supports the reflow profiles required by OEM tier-1 production lines. Compared with newer S12XEP parts, the XA256CAAR remains attractive for service and second-source qualification.
Recommended
CAN/LIN Gateway Node
With multiple CAN and LINbus interfaces integrated, the MC9S12XA256CAAR serves as a gateway between in-vehicle network segments. The XGATE engine handles CAN frame filtering and forwarding at line speed without taxing the main CPU, freeing the S12X core for routing tables and diagnostic services (UDS/KWP2000). The 80 MHz bus supports the throughput required by CAN-FD-like applications, and the 256 KB Flash accommodates ISO 14229 and OEM-specific transport-layer stacks. The LQFP-80 footprint eases two-layer PCB stack-ups typical of gateway modules.
Recommended
HVAC Control Board
The MC9S12XA256CAAR fits HVAC control boards requiring moderate Flash (256 KB), PWM channels for blower/actuator drive, and ADC inputs for temperature/sensor reading. The 8-channel 10-bit ADC can scan mixed NTC thermistor and pressure-sensor inputs, while the PWM channels drive BLDC blower motors through external FET bridges. Operating from a 2.5 V core with 5 V-tolerant I/O, the device interfaces to legacy HVAC front-panel switches and displays without level shifters.
Recommended
Industrial PLC I/O Module
For industrial PLC digital and analog I/O modules, the MC9S12XA256CAAR provides 59 GPIO, multiple SCI/UART channels for module-to-bus communication, and PWM outputs for valve/actuator control. The XGATE co-processor handles fast I/O scanning while the main CPU executes IEC 61131 application logic. The wide operating temperature range and LQFP-80 package suit DIN-rail-mounted industrial enclosures. The integrated WDT and LVD/POR functions are critical for fail-safe industrial operation.
Recommended
Small BLDC Motor Controller
The MC9S12XA256CAAR can drive small BLDC motors using its PWM channels and ADC inputs for back-EMF sensing. The XGATE co-processor offloads PWM timing-critical tasks (commutation, FOC math helpers), and 256 KB Flash fits sensored or sensorless BLDC algorithms including startup, ramp, and fault handling. With SCI/SPI ports, the controller interfaces to higher-level ECUs over CAN or LIN. The 80-LQFP package supports the heat dissipation needed for moderate-current applications with external FETs.
Recommended
Sensor Fusion Front-End
As a sensor-hub MCU, the MC9S12XA256CAAR aggregates data from SPI/I2C-connected accelerometers, gyros, and pressure sensors, performs basic fusion math, and outputs the result via CAN. The XGATE co-processor services high-rate SPI/I2C bursts without interrupt saturation, while the 16 KB RAM buffers sensor frames between fusion cycles. The 256 KB Flash accommodates manufacturer-specific calibration tables and is sufficient for production-grade automotive sensor nodes.
Recommended
Recommended Products Summary
Engineering reference data for MC9S12XA256CAAR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9S12XA256CAA | MC9S12XDT256VAA | MC9S12XD256MAA | MC9S12XDG128CAA | MC9S12XEG128MAA |
|---|---|---|---|---|---|---|
| Package | 80-LQFP (14x14 mm) | 80-LQFP (14x14 mm) - same | 80-LQFP (14x14 mm) - same | 80-LQFP - same | 80-LQFP (14x14 mm) - same | 80-LQFP - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Core Processor | HCS12X | HCS12X | HCS12X | HCS12X | HCS12X | HCS12X |
| Maximum CPU Frequency | 80 MHz | 80 MHz | 80 MHz | 80 MHz | 40 MHz | 50 MHz |
| Program Memory Size | 256 KB Flash | 256 KB Flash | 256 KB Flash | 256 KB Flash | 128 KB Flash | 128 KB Flash |
| RAM Size | 16 KB | 16 KB | 16 KB | 16 KB | 12 KB | 12 KB |
| EEPROM Size | 4 KB | 4 KB | 4 KB | 4 KB | 2 KB | 2 KB |
| Co-Processor | XGATE | XGATE | XGATE + ETPU | XGATE | XGATE | XGATE |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Active (limited) |
Key Differentiators
- Integrated XGATE co-processor for peripheral offload (vs MC9S12XDT256VAA)
- 256 KB Flash matches standard body-controller code density (vs MC9S12XDG128CAA)
- 80 MHz bus vs newer 50 MHz S12XE variants (vs MC9S12XEG128MAA)
Design Notes
Supply the MC9S12XA256CAAR from a regulated 2.5 V rail (VDDR/VSSX pair) capable of delivering at least 80 mA peak. Place a 10 uF tantalum or ceramic bulk capacitor close to the VDDR pin and a 100 nF decoupling capacitor at every adjacent VDD/VSS pair. For automotive modules, add reverse-battery and load-dump protection (TVS diode + series inductance) ahead of the regulator; the on-chip POR and LVD do not substitute for external supply supervision.
Do not confuse the MC9S12XA256CAAR (S12XA sub-family, 256 KB Flash, 80 MHz) with the visually similar MC9S12XEP100 (S12XE sub-family, 1 MB Flash, 50 MHz). Their Flash sizes, peripheral sets, and reference manuals differ, so firmware built for one will not run on the other without rework. Always confirm the full MPN before programming or sourcing. The 'R' suffix on CAAR denotes tape-and-reel packaging only - same die, same part.
Route the EXTAL/XTAL oscillator traces short and symmetric, with the crystal placed within 5 mm of the MCU. Keep PLL-filter components (capacitor to VDDPLL/SSPLL) close to their respective pins and isolated from noisy digital traces. For EMC-sensitive designs, place a ground guard ring around the oscillator cell and use a 4-layer PCB with a continuous ground plane beneath the MCU.
Compliance Information
RoHS compliance and lead-free confirmed via distributor listings. AEC-Q100 status not explicitly stated in the verified web data; HCS12X family is widely used in automotive but the CAAR suffix is industrial-grade - confirm with NXP for AEC-Q100 qualified alternatives if required.
