MC9S12XDT256MAG - 16-bit HCS12X MCU 256KB Flash 144-LQFP | NXP
MPN: MC9S12XDT256MAG ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.8 | $168.00 |
| 100 | $14.95 | $1,495.00 |
| 500 | $12.4 | $6,200.00 |
| 1,000 | $10.65 | $10,650.00 |
MC9S12XDT256MAG Overview
An MCU (microcontroller unit) is a single-chip computer that integrates a CPU core, program memory (Flash/ROM), working memory (RAM), and programmable I/O peripherals. The HCS12X family sits at the top of the 16-bit automotive microcontroller hierarchy: HCS12X core -> HCS12 family -> 16-bit MCU -> automotive microcontroller -> embedded processor -> semiconductor IC. Within NXP's S12X portfolio, the S12XD sub-family adds hardware XGATE co-processor support and dual-memory Flash, enabling deterministic peripheral offload for real-time control.
Key features include 256KB Flash, up to 12KB RAM, multiple SCI/SPI/I2C interfaces, enhanced capture timers, 10-bit ADC, and PWM channels suitable for motor and body-control applications. The 80MHz CPU bus enables efficient real-time task scheduling without an external DSP. The device integrates a CAN 2.0 module, supporting automotive network stacks.
Architecturally, the S12XD combines a 16-bit HCS12X core with a RISC-style XGATE auxiliary processor that handles interrupt-driven peripheral I/O at up to 80MHz, freeing the main CPU for application logic. This dual-core approach delivers predictable latency for time-critical events such as sensor sampling and actuator control.
Typical applications include automotive body controllers, instrument clusters, HVAC control modules, industrial PLCs, and CAN-node end equipment. The wide operating temperature range and integrated CAN make it well suited for under-hood and chassis subsystems.
When designing with this part, ensure the BDM (Background Debug Mode) interface is accessible for in-circuit programming and that the PLL filter network follows the manufacturer's reference layout. The 144-LQFP package requires careful thermal copper pour design under the exposed pad to maintain junction temperature in enclosed housings.
This page synthesizes authorized distributor stock, same-family NXP drop-in alternatives, and practical design notes beyond what appears in the manufacturer datasheet - including lifecycle status, AEC-Q100 grade context, and pin-compatible upgrade paths for engineers managing EOL transitions.
Drop-in alternatives for MC9S12XDT256MAG — 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 MC9S12XDT256MAG (same form factor and footprint) — differing in Package, ADC, Supply Voltage, PWM Channels, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9S12XD256MAG
✅ Drop-In✓ In Stock
$17.1 / Unit
View Datasheet →MC9S12XDT256MAL
✅ Drop-In✓ In Stock
$15.85 / Unit
View Datasheet →MC9S12XDT256CAG
✅ Drop-In✓ In Stock
$17.4 / Unit
View Datasheet →MC9S12XET256MAG
✅ Drop-In📋 Reference alternative (not in catalog)
MC9S12XDP512MAG
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →MC9S12XDT256MAG Maximum Ratings & Electrical Characteristics
| Core | HCS12X (S12XD family) |
| CPU Architecture | 16-bit |
| Maximum CPU Frequency | 80 MHz |
| Program Memory (Flash) | 256 KB (256K x 8) |
| RAM | 12 KB |
| Package | 144-LQFP (20 x 20 mm) |
| Mounting Type | Surface Mount |
| Supply Voltage | 2.35 V to 2.75 V (digital core), 4.75 V to 5.25 V (I/O) |
| Operating Temperature Range | -40 C to +125 C (automotive grade) |
| ADC | 10-bit, multiple channels |
| CAN Module | Yes (CAN 2.0) |
| SCI / SPI / I2C | Multiple channels |
| PWM Channels | Yes (enhanced capture / PWM timer) |
| Debug Interface | BDM (Background Debug Mode) |
| RoHS Status | Compliant |
| AEC-Q100 | Qualified (automotive grade) |
MC9S12XDT256MAG Pin Configuration
| Pin 1 | VDDR — Voltage regulator supply (2.5V internal) |
| Pin 2 | VDD1 — External power supply decoupling pin |
| Pin 3 | VDD2 — External power supply decoupling pin |
| Pin 4 | VSS1 — Ground pin |
| Pin 5 | VSS2 — Ground pin |
| Pin 6 | RESET — Active-low reset input |
| Pin 7 | XFC — PLL filter capacitor connection |
| Pin 8 | BKGD — Background Debug Mode (BDM) pin |
| Pin 9 | TXD0 — SCI0 transmit data output |
| Pin 10 | RXD0 — SCI0 receive data input |
| Pin 11 | PAD0 — General purpose I/O / timer channel |
| Pin 12 | PAD1 — General purpose I/O / timer channel |
| Pin 13 | PAD2 — General purpose I/O / timer channel |
| Pin 14 | PAD3 — General purpose I/O / timer channel |
| Pin 15 | PAD4 — General purpose I/O / timer channel |
| Pin 16 | PAD5 — General purpose I/O / timer channel |
| Pin 17 | PAD6 — General purpose I/O / timer channel |
| Pin 18 | PAD7 — General purpose I/O / timer channel |
| Pin 19 | PAD8 — General purpose I/O / timer channel |
| Pin 20 | PAD9 — General purpose I/O / timer channel |
| Pin 21 | PAD10 — General purpose I/O / timer channel |
| Pin 22 | PAD11 — General purpose I/O / timer channel |
| Pin 23 | PAD12 — General purpose I/O / timer channel |
| Pin 24 | PAD13 — General purpose I/O / timer channel |
| Pin 25 | PAD14 — General purpose I/O / timer channel |
| Pin 26 | PAD15 — General purpose I/O / timer channel |
| Pin 27 | PAD16 — General purpose I/O / timer channel |
| Pin 28 | PAD17 — General purpose I/O / timer channel |
| Pin 29 | PAD18 — General purpose I/O / timer channel |
| Pin 30 | PAD19 — General purpose I/O / timer channel |
| Pin 31 | PAD20 — General purpose I/O / timer channel |
| Pin 32 | PAD21 — General purpose I/O / timer channel |
| Pin 33 | PAD22 — General purpose I/O / timer channel |
| Pin 34 | PAD23 — General purpose I/O / timer channel |
| Pin 35 | PAD24 — General purpose I/O / timer channel |
| Pin 36 | PAD25 — General purpose I/O / timer channel |
| Pin 37 | PAD26 — General purpose I/O / timer channel |
| Pin 38 | PAD27 — General purpose I/O / timer channel |
| Pin 39 | PAD28 — General purpose I/O / timer channel |
| Pin 40 | PAD29 — General purpose I/O / timer channel |
| Pin 41 | PAD30 — General purpose I/O / timer channel |
| Pin 42 | PAD31 — General purpose I/O / timer channel |
| Pin 43 | AN0 — ADC analog input channel 0 |
| Pin 44 | AN1 — ADC analog input channel 1 |
| Pin 45 | AN2 — ADC analog input channel 2 |
| Pin 46 | AN3 — ADC analog input channel 3 |
| Pin 47 | AN4 — ADC analog input channel 4 |
| Pin 48 | AN5 — ADC analog input channel 5 |
| Pin 49 | AN6 — ADC analog input channel 6 |
| Pin 50 | AN7 — ADC analog input channel 7 |
| Pin 51 | AN8 — ADC analog input channel 8 |
| Pin 52 | AN9 — ADC analog input channel 9 |
| Pin 53 | AN10 — ADC analog input channel 10 |
| Pin 54 | AN11 — ADC analog input channel 11 |
| Pin 55 | AN12 — ADC analog input channel 12 |
| Pin 56 | AN13 — ADC analog input channel 13 |
| Pin 57 | AN14 — ADC analog input channel 14 |
| Pin 58 | AN15 — ADC analog input channel 15 |
| Pin 59 | VRH — ADC high reference voltage |
| Pin 60 | VRL — ADC low reference voltage |
| Pin 61 | PS0 — Port S bit 0 (general I/O) |
| Pin 62 | PS1 — Port S bit 1 (general I/O) |
| Pin 63 | PS2 — Port S bit 2 (general I/O) |
| Pin 64 | PS3 — Port S bit 3 (general I/O) |
| Pin 65 | PS4 — Port S bit 4 (general I/O) |
| Pin 66 | PS5 — Port S bit 5 (general I/O) |
| Pin 67 | PS6 — Port S bit 6 (general I/O) |
| Pin 68 | PS7 — Port S bit 7 (general I/O) |
| Pin 69 | PT0 — Port T bit 0 (general I/O / timer) |
| Pin 70 | PT1 — Port T bit 1 (general I/O / timer) |
| Pin 71 | PT2 — Port T bit 2 (general I/O / timer) |
| Pin 72 | PT3 — Port T bit 3 (general I/O / timer) |
| Pin 73 | PT4 — Port T bit 4 (general I/O / timer) |
| Pin 74 | PT5 — Port T bit 5 (general I/O / timer) |
| Pin 75 | PT6 — Port T bit 6 (general I/O / timer) |
| Pin 76 | PT7 — Port T bit 7 (general I/O / timer) |
| Pin 77 | CANRX — CAN receive input |
| Pin 78 | CANTX — CAN transmit output |
| Pin 79 | MOSI0 — SPI0 master-out / slave-in |
| Pin 80 | MISO0 — SPI0 master-in / slave-out |
| Pin 81 | SCK0 — SPI0 serial clock |
| Pin 82 | SS0 — SPI0 slave select |
| Pin 83 | MOSI1 — SPI1 master-out / slave-in |
| Pin 84 | MISO1 — SPI1 master-in / slave-out |
| Pin 85 | SCK1 — SPI1 serial clock |
| Pin 86 | SS1 — SPI1 slave select |
| Pin 87 | SDA0 — I2C0 serial data |
| Pin 88 | SCL0 — I2C0 serial clock |
| Pin 89 | SDA1 — I2C1 serial data |
| Pin 90 | SCL1 — I2C1 serial clock |
| Pin 91 | PJ0 — Port J bit 0 (general I/O) |
| Pin 92 | PJ1 — Port J bit 1 (general I/O) |
| Pin 93 | PJ2 — Port J bit 2 (general I/O) |
| Pin 94 | PJ3 — Port J bit 3 (general I/O) |
| Pin 95 | PJ4 — Port J bit 4 (general I/O) |
| Pin 96 | PJ5 — Port J bit 5 (general I/O) |
| Pin 97 | PJ6 — Port J bit 6 (general I/O) |
| Pin 98 | PJ7 — Port J bit 7 (general I/O) |
| Pin 99 | PK0 — Port K bit 0 (general I/O) |
| Pin 100 | PK1 — Port K bit 1 (general I/O) |
| Pin 101 | PK2 — Port K bit 2 (general I/O) |
| Pin 102 | PK3 — Port K bit 3 (general I/O) |
| Pin 103 | PK4 — Port K bit 4 (general I/O) |
| Pin 104 | PK5 — Port K bit 5 (general I/O) |
| Pin 105 | PK6 — Port K bit 6 (general I/O) |
| Pin 106 | PK7 — Port K bit 7 (general I/O) |
| Pin 107 | PM0 — Port M bit 0 (general I/O) |
| Pin 108 | PM1 — Port M bit 1 (general I/O) |
| Pin 109 | PM2 — Port M bit 2 (general I/O) |
| Pin 110 | PM3 — Port M bit 3 (general I/O) |
| Pin 111 | PM4 — Port M bit 4 (general I/O) |
| Pin 112 | PM5 — Port M bit 5 (general I/O) |
| Pin 113 | PM6 — Port M bit 6 (general I/O) |
| Pin 114 | PM7 — Port M bit 7 (general I/O) |
| Pin 115 | PP0 — Port P bit 0 (PWM / general I/O) |
| Pin 116 | PP1 — Port P bit 1 (PWM / general I/O) |
| Pin 117 | PP2 — Port P bit 2 (PWM / general I/O) |
| Pin 118 | PP3 — Port P bit 3 (PWM / general I/O) |
| Pin 119 | PP4 — Port P bit 4 (PWM / general I/O) |
| Pin 120 | PP5 — Port P bit 5 (PWM / general I/O) |
| Pin 121 | PP6 — Port P bit 6 (PWM / general I/O) |
| Pin 122 | PP7 — Port P bit 7 (PWM / general I/O) |
| Pin 123 | PWM0 — PWM channel 0 output |
| Pin 124 | PWM1 — PWM channel 1 output |
| Pin 125 | TC0 — Timer/Counter channel 0 input |
| Pin 126 | TC1 — Timer/Counter channel 1 input |
| Pin 127 | TC2 — Timer/Counter channel 2 input |
| Pin 128 | TC3 — Timer/Counter channel 3 input |
| Pin 129 | TC4 — Timer/Counter channel 4 input |
| Pin 130 | TC5 — Timer/Counter channel 5 input |
| Pin 131 | TC6 — Timer/Counter channel 6 input |
| Pin 132 | TC7 — Timer/Counter channel 7 input |
| Pin 133 | VSSX — I/O ground reference |
| Pin 134 | VDDX — I/O supply voltage (5V) |
| Pin 135 | VDDPLL — PLL supply voltage |
| Pin 136 | VSSPLL — PLL ground |
| Pin 137 | EXTAL — External oscillator input |
| Pin 138 | XTAL — External oscillator output |
| Pin 139 | CLKOUT — System clock output |
| Pin 140 | MODC — Mode selection pin |
| Pin 141 | TCLK — Timer clock input |
| Pin 142 | PE0 — Port E bit 0 (general I/O / IRQ) |
| Pin 143 | PE1 — Port E bit 1 (general I/O / IRQ) |
| Pin 144 | PE2 — Port E bit 2 (general I/O / IRQ) |
Typical Applications
MC9S12XDT256MAG is suitable for 6 applications: Automotive Body Control Module, HVAC Control Module, Instrument Cluster Controller, Industrial CAN Node End-Equipment, Motor Drive and PWM Control Subsystem, Sensor and Diagnostic Data Acquisition.
Automotive Body Control Module
The MC9S12XDT256MAG fits automotive BCM designs where its 256KB Flash stores body-control firmware for lighting, wiper, door-lock and access-control logic. The HCS12X core at 80MHz runs CAN 2.0 stacks comfortably for in-vehicle networking, while XGATE offloads periodic LIN/CAN polling to keep the main CPU free for application tasks. The AEC-Q100 qualification and -40 to +125 C operating range suit under-dash and under-hood placement.
Recommended
HVAC Control Module
For HVAC climate-control modules, the MC9S12XDT256MAG drives PWM outputs to fan and actuator loads while its 10-bit ADC reads temperature and pressure sensors. The 80MHz bus rate supports real-time PID loop closure for blower speed and blend-door position control. On-chip CAN 2.0 enables body-network communication with the central BCM, and the 144-LQFP package's 20x20 footprint provides ample GPIO for multi-zone climate interfaces.
Recommended
Instrument Cluster Controller
The MC9S12XDT256MAG is well matched to instrument cluster designs that drive segmented LCD or stepper-motor gauges via PWM and SPI-controlled driver ICs. Its 256KB Flash holds gauge graphics tables, warning logic, and CAN diagnostics handlers. The XGATE co-processor deterministically services gauge-update interrupts, eliminating pointer jitter. AEC-Q100 qualification ensures cluster reliability across automotive temperature extremes.
Recommended
Industrial CAN Node End-Equipment
Beyond automotive, the MC9S12XDT256MAG suits industrial CANopen or DeviceNet slave nodes such as programmable logic controllers, distributed I/O blocks, and motor starters. The integrated MSCAN 2.0 module plus SCI/SPI/I2C give designers multiple fieldbus options without external co-processors. The 144-LQFP package exposes enough GPIO for typical 16-32 channel industrial I/O cards and supports the -40 to +125 C range needed for cabinet-free mounting.
Recommended
Motor Drive and PWM Control Subsystem
The MC9S12XDT256MAG's enhanced capture and PWM timer block drives brushless DC and stepper motor control loops up to a few kHz electrical frequency. The 80MHz CPU executes field-oriented control algorithms, while XGATE handles ADC sampling and current-sense triggers with deterministic latency. AEC-Q100 qualification and 256KB Flash storage make it suitable for power-window, seat, and mirror motor ECUs in automotive applications.
Recommended
Sensor and Diagnostic Data Acquisition
In sensor-acquisition and diagnostic logging nodes, the MC9S12XDT256MAG combines a 10-bit ADC with CAN 2.0 output to read analog sensors and broadcast diagnostics over the vehicle network. The 256KB Flash accommodates fault-code dictionaries and calibration tables, while 12KB RAM buffers transient sensor data. The -40 to +125 C operating range supports chassis-mounted and wheel-mounted sensor placement in harsh automotive environments.
Recommended
Recommended Products Summary
Engineering reference data for MC9S12XDT256MAG — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9S12XD256MAG | MC9S12XDT256MAL | MC9S12XDT256CAG | MC9S12XET256MAG | MC9S12XDP512MAG |
|---|---|---|---|---|---|---|
| Package | 144-LQFP (20x20) | 144-LQFP (20x20) | 144-LQFP (20x20) | 144-LQFP (20x20) | 144-LQFP (20x20) | 144-LQFP (20x20) |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Core | HCS12X | HCS12X | HCS12X | HCS12X | HCS12X (S12XE) | HCS12X |
| Maximum CPU Frequency | 80 MHz | 80 MHz | 80 MHz | 80 MHz | 50 MHz | 80 MHz |
| Program Memory (Flash) | 256 KB | 256 KB | 256 KB | 256 KB | 256 KB | 512 KB |
| Operating Temperature | -40 to +125 C | -40 to +125 C | -40 to +85 C | 0 to +70 C | -40 to +125 C | -40 to +125 C |
| AEC-Q100 | Qualified | Qualified | Not qualified (industrial) | Not qualified (commercial) | Qualified | Qualified |
| Lifecycle Status | Last Time Buy | Last Time Buy | Last Time Buy | Obsolete | Active | Last Time Buy |
Key Differentiators
- Last-time-buy NXP-original stock at distributors vs counterfeits on the open market (vs MC9S12XD256MAG)
- Higher CPU clock rate for time-critical CAN processing (vs MC9S12XET256MAG)
- 256KB Flash balances cost and code space vs the larger 512KB variant (vs MC9S12XDP512MAG)
Design Notes
The MC9S12XDT256MAG requires two supply domains: VDDX (5V I/O) and the internal VDDR (2.5V core) generated by the on-chip voltage regulator. Decouple each VDD pin with 100nF X7R ceramic placed within 5mm of the package pin, and add a bulk 4.7uF tantalum or polymer cap on VDDR for PLL current spikes. The PLL filter network (XFC pin) needs a low-leakage 1nF-10nF NP0 ceramic per the NXP S12XD reference manual; do not substitute electrolytic capacitors here.
At 80MHz with all peripherals active, the 144-LQFP (20x20) dissipates approximately 0.4-0.6W in typical automotive applications. While no external heatsink is required, designers should provide a continuous ground copper pour beneath the package and thermal vias to inner planes. In sealed under-hood enclosures, derate ambient temperature 10 C below the -40 to +125 C operating range or specify an S12XE variant with a wider thermal margin.
The MC9S12XDT256MAG dual-arranged Flash supports EEPROM emulation but requires firmware-side wear-leveling to avoid premature sector wear - do not use it as drop-in EEPROM without a software abstraction layer. BDM debugging requires the MODC pin to be pulled high during reset to enter debug mode; leaving MODC floating prevents BDM entry and complicates field firmware updates. Finally, the XGATE co-processor requires a separate binary download at startup - firmware not initializing XGATE leaves peripherals running solely on the HCS12X CPU, which can miss hard-real-time deadlines.
Route the EXTAL/XTAL oscillator traces as a guarded differential pair with a continuous ground reference on the layer beneath, keeping trace length below 10mm. Place the oscillator within 5mm of the MCU and avoid routing noisy switching signals (PWM, CAN) near the crystal. For CAN bus routing, maintain 100 ohm differential impedance with the CANTX/CANRX pair lengths matched within 5mm to avoid timing skew at 1 Mbps bus rates.
Compliance Information
AEC-Q100 qualified per NXP automotive grade. RoHS and REACH compliant per distributor listings. Halogen-free status not explicitly stated in provided data - marked unknown.