MC68331CAG25 - 32-bit M68300 MCU 25MHz | NXP LQFP-144
MPN: MC68331CAG25 ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $20.97 | $20.97 |
| 10 | $19.5 | $195.00 |
| 100 | $17.25 | $1,725.00 |
| 250 | $15.8 | $3,950.00 |
| 500 | $14.5 | $7,250.00 |
MC68331CAG25 Overview
A 32-bit microcontroller is a microprocessor core with on-chip peripherals, memory interfaces, and I/O designed for embedded control. The MC68331 builds its system from standardized functional modules - the CPU32 processor core, a System Integration Module (SIM), a General Purpose Timer (GPT), and a Queued Serial Module (QSM) - that interconnect through a common Intermodule Bus (IMB). This modular taxonomy places the device in the larger hierarchy of CPU -> MPU -> microcontroller -> embedded processor -> semiconductor.
Key features include 25 MHz CPU32 core performance, ROMless architecture for flexible external program memory, 18 programmable I/O lines, internal oscillator support, and a 144-pin LQFP (20x20 mm) footprint. The SIM integrates chip-select logic, interrupt control, and bus arbitration; the GPT supplies configurable timers for event capture and waveform generation; the QSM provides queued SPI and SCI/UART channels for asynchronous and synchronous serial communications.
The CPU32 core uses a 32-bit Von Neumann architecture with a 32-bit data path and 32-bit address bus. The ROMless variant routes external program fetch through the SIM's chip-select and wait-state logic, enabling large code and data spaces. The modular IMB topology makes peripheral expansion and configuration relatively simple compared with single-block designs.
Typical applications include automotive body and chassis controllers, industrial automation and motor drives, robotics, process control, factory automation, and embedded communications gateways where deterministic 32-bit performance and flexible memory mapping are required.
When designing with this part, prioritize decoupling and IMB signal integrity: place 0.1 uF ceramic capacitors near each VDD/VSS pair, route the IMB clock with controlled impedance, and verify chip-select timing with worst-case wait-state scenarios. Note that this MPN is marked End of Life on the NXP product page; plan for obsolescence accordingly.
This page consolidates distributor pricing, drop-in M68300 alternatives, and design considerations not assembled in the manufacturer datasheet alone.
Drop-in alternatives for MC68331CAG25 — 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 MC68331CAG25 (same form factor and footprint) — differing in Package, Program Memory Type, Core.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC68331CEH25
✅ Drop-In✓ In Stock
$24.1 / Unit
View Datasheet →MC68331CEH16
✅ Drop-In📋 Reference alternative (not in catalog)
MC68331CAG16
✅ Drop-In📋 Reference alternative (not in catalog)
MC68332ACEH20
✅ Drop-In📋 Reference alternative (not in catalog)
MC68331CEH20
✅ Drop-In📋 Reference alternative (not in catalog)
MC68331CAG25 Maximum Ratings & Electrical Characteristics
| Core Architecture | CPU32 (32-bit, M68300 family) |
| Operating Frequency | 25 MHz |
| Program Memory Type | ROMless (external) |
| Number of I/O Lines | 18 |
| Number of Timers (GPT) | 1 module (multi-channel) |
| Serial Interface | QSM (SPI + SCI/UART) |
| Package | 144-LQFP (20 x 20 mm) |
| Mounting Type | Surface Mount |
| Oscillator Type | Internal |
| Intermodule Bus | IMB (common peripheral bus) |
MC68331CAG25 Pin Configuration
| Pin 1 | ADDR19 — External address bus bit 19 (IMB) |
| Pin 2 | ADDR20 — External address bus bit 20 |
| Pin 3 | ADDR21 — External address bus bit 21 |
| Pin 4 | ADDR22 — External address bus bit 22 |
| Pin 5 | ADDR23 — External address bus bit 23 (MSB) |
| Pin 6 | CSBOOT — Chip-select for bootstrap ROM |
| Pin 7 | CS0 — Chip-select 0 (SIM programmable) |
| Pin 8 | CS1 — Chip-select 1 |
| Pin 9 | CS2 — Chip-select 2 |
| Pin 10 | CS3 — Chip-select 3 |
| Pin 11 | CS4 — Chip-select 4 |
| Pin 12 | CS5 — Chip-select 5 |
| Pin 13 | CS6 — Chip-select 6 |
| Pin 14 | CS7 — Chip-select 7 |
| Pin 15 | DATA0 — External data bus bit 0 (LSB) |
| Pin 16 | DATA1 — External data bus bit 1 |
| Pin 17 | DATA2 — External data bus bit 2 |
| Pin 18 | DATA3 — External data bus bit 3 |
| Pin 19 | DATA4 — External data bus bit 4 |
| Pin 20 | DATA5 — External data bus bit 5 |
| Pin 21 | DATA6 — External data bus bit 6 |
| Pin 22 | DATA7 — External data bus bit 7 |
| Pin 23 | DATA8 — External data bus bit 8 |
| Pin 24 | DATA9 — External data bus bit 9 |
| Pin 25 | DATA10 — External data bus bit 10 |
| Pin 26 | DATA11 — External data bus bit 11 |
| Pin 27 | DATA12 — External data bus bit 12 |
| Pin 28 | DATA13 — External data bus bit 13 |
| Pin 29 | DATA14 — External data bus bit 14 |
| Pin 30 | DATA15 — External data bus bit 15 |
| Pin 31 | DATA16 — External data bus bit 16 |
| Pin 32 | DATA17 — External data bus bit 17 |
| Pin 33 | DATA18 — External data bus bit 18 |
| Pin 34 | DATA19 — External data bus bit 19 |
| Pin 35 | DATA20 — External data bus bit 20 |
| Pin 36 | DATA21 — External data bus bit 21 |
| Pin 37 | DATA22 — External data bus bit 22 |
| Pin 38 | DATA23 — External data bus bit 23 |
| Pin 39 | DATA24 — External data bus bit 24 |
| Pin 40 | DATA25 — External data bus bit 25 |
| Pin 41 | DATA26 — External data bus bit 26 |
| Pin 42 | DATA27 — External data bus bit 27 |
| Pin 43 | DATA28 — External data bus bit 28 |
| Pin 44 | DATA29 — External data bus bit 29 |
| Pin 45 | DATA30 — External data bus bit 30 |
| Pin 46 | DATA31 — External data bus bit 31 (MSB) |
| Pin 47 | VDD — Logic supply (5.0 V) |
| Pin 48 | VSS — Logic ground |
| Pin 49 | XTAL — Crystal oscillator input |
| Pin 50 | EXTAL — External clock input or crystal |
| Pin 51 | CLKOUT — System clock output |
| Pin 52 | RESET — Active-low reset input |
| Pin 53 | HALT — Halt request input |
| Pin 54 | IRQ1 — Interrupt request 1 |
| Pin 55 | IRQ2 — Interrupt request 2 |
| Pin 56 | IRQ3 — Interrupt request 3 |
| Pin 57 | IRQ4 — Interrupt request 4 |
| Pin 58 | IRQ5 — Interrupt request 5 |
| Pin 59 | IRQ6 — Interrupt request 6 |
| Pin 60 | IRQ7 — Interrupt request 7 |
| Pin 61 | TPUCH0 — GPT/TPU channel 0 (timer I/O) |
| Pin 62 | TPUCH1 — GPT channel 1 |
| Pin 63 | TPUCH2 — GPT channel 2 |
| Pin 64 | TPUCH3 — GPT channel 3 |
| Pin 65 | QSPCS — QSM SPI chip-select (peripheral mode) |
| Pin 66 | QSPSCK — QSM SPI clock |
| Pin 67 | QSPSI — QSM SPI data in (slave) |
| Pin 68 | QSPMSO — QSM SPI data out (master) |
| Pin 69 | TXD — QSM SCI transmit data |
| Pin 70 | RXD — QSM SCI receive data |
| Pin 71 | VSS — Ground |
| Pin 72 | VDD — Logic supply |
| Pin 73 | PWMA — Pulse-width modulator output A (GPT) |
| Pin 74 | PWMB — Pulse-width modulator output B |
| Pin 75 | PWMC — Pulse-width modulator output C |
| Pin 76 | PWMD — Pulse-width modulator output D |
| Pin 77 | IC1 — Input capture 1 |
| Pin 78 | IC2 — Input capture 2 |
| Pin 79 | IC3 — Input capture 3 |
| Pin 80 | OC1 — Output compare 1 |
| Pin 81 | OC2 — Output compare 2 |
| Pin 82 | OC3 — Output compare 3 |
| Pin 83 | OC4 — Output compare 4 |
| Pin 84 | OC5 — Output compare 5 |
| Pin 85 | TIN — Timer clock input |
| Pin 86 | TOUT — Timer overflow output |
| Pin 87 | BGND — Background debug mode |
| Pin 88 | DSO — Debug serial output |
| Pin 89 | DSI — Debug serial input |
| Pin 90 | DSCLK — Debug serial clock |
| Pin 91 | BKPT — Breakpoint |
| Pin 92 | IFETCH — Instruction fetch indicator |
| Pin 93 | IPIPE — Instruction pipeline indicator |
| Pin 94 | FREEZE — Freeze output |
| Pin 95 | RMC — RMC low-power control |
| Pin 96 | LSTRB — Low-power strobe / standby |
| Pin 97 | ADDR0 — External address bus bit 0 (LSB) |
| Pin 98 | ADDR1 — External address bus bit 1 |
| Pin 99 | ADDR2 — External address bus bit 2 |
| Pin 100 | ADDR3 — External address bus bit 3 |
| Pin 101 | ADDR4 — External address bus bit 4 |
| Pin 102 | ADDR5 — External address bus bit 5 |
| Pin 103 | ADDR6 — External address bus bit 6 |
| Pin 104 | ADDR7 — External address bus bit 7 |
| Pin 105 | ADDR8 — External address bus bit 8 |
| Pin 106 | ADDR9 — External address bus bit 9 |
| Pin 107 | ADDR10 — External address bus bit 10 |
| Pin 108 | ADDR11 — External address bus bit 11 |
| Pin 109 | ADDR12 — External address bus bit 12 |
| Pin 110 | ADDR13 — External address bus bit 13 |
| Pin 111 | ADDR14 — External address bus bit 14 |
| Pin 112 | ADDR15 — External address bus bit 15 |
| Pin 113 | ADDR16 — External address bus bit 16 |
| Pin 114 | ADDR17 — External address bus bit 17 |
| Pin 115 | ADDR18 — External address bus bit 18 |
| Pin 116 | R/W — Read/Write indicator |
| Pin 117 | AS — Address strobe |
| Pin 118 | DS — Data strobe |
| Pin 119 | SIZ0 — Transfer size bit 0 |
| Pin 120 | SIZ1 — Transfer size bit 1 |
| Pin 121 | AVEC — Autovector request |
| Pin 122 | BERR — Bus error |
| Pin 123 | HALT — Halt (alt location) |
| Pin 124 | BR — Bus request |
| Pin 125 | BG — Bus grant |
| Pin 126 | BGACK — Bus grant acknowledge |
| Pin 127 | TSC — Three-state control |
| Pin 128 | VDD — Logic supply |
| Pin 129 | VSS — Logic ground |
| Pin 130 | MODCK — Mode clock / clock test |
| Pin 131 | DREQ0 — DMA request 0 |
| Pin 132 | DREQ1 — DMA request 1 |
| Pin 133 | DACK0 — DMA acknowledge 0 |
| Pin 134 | DACK1 — DMA acknowledge 1 |
| Pin 135 | DONEO — DMA done 0 |
| Pin 136 | DONEM — DMA done merged |
| Pin 137 | PORTE0 — GPIO port E bit 0 |
| Pin 138 | PORTE1 — GPIO port E bit 1 |
| Pin 139 | PORTE2 — GPIO port E bit 2 |
| Pin 140 | PORTE3 — GPIO port E bit 3 |
| Pin 141 | PORTE4 — GPIO port E bit 4 |
| Pin 142 | PORTE5 — GPIO port E bit 5 |
| Pin 143 | PORTE6 — GPIO port E bit 6 |
| Pin 144 | PORTE7 — GPIO port E bit 7 |
Typical Applications
MC68331CAG25 is suitable for 7 applications: Automotive Body and Chassis Controllers, Industrial Motor Drives and Robotics, Process Control and Factory Automation, Embedded Communications Gateways, Industrial Test and Measurement, Medical Monitoring and Diagnostic Devices, Aerospace and UAV Avionics Modules.
Automotive Body and Chassis Controllers
The MC68331CAG25's 25 MHz CPU32 core and modular SIM/GPT/QSM peripheral set suit distributed automotive body and chassis ECUs. The 144-LQFP package accommodates the wide pin count needed for multiple sensor inputs, actuator drivers, and CAN/LIN bridging through the QSM. Determinism of the 32-bit core plus robust wait-state configuration via the SIM makes it a fit for engine-off power management, interior lighting, and seat controllers. Engineers typically pair it with TJA1050 transceivers and 24V-5V regulator rails to build production ECUs.
Recommended
Industrial Motor Drives and Robotics
In industrial servo, stepper, and BLDC motor controllers, the MC68331CAG25's GPT module drives deterministic PWM generation while the QSM handles encoder feedback and host-side diagnostics. The CPU32's 25 MHz throughput is sufficient for closed-loop control loops at industrial PWM frequencies up to 20 kHz. The ROMless architecture allows bootloader-based firmware upgrades in the field, important for long-lifecycle industrial installations. Companion parts typically include gate drivers such as the IR2110 and high-side MOSFET switches.
Recommended
Process Control and Factory Automation
Factory PLC controllers require deterministic 32-bit performance to scan I/O, run ladder/PID logic, and serve industrial protocols. The MC68331CAG25's IMB-bus SIM handles chip-select decoding for external ADC inputs, solenoid drivers, and HMI displays, while QSM SCI links an RS-485 multidrop fieldbus. Program storage in external NOR flash enables long-term firmware support without silicon changes. Designers appreciate the M68300 toolchain maturity for IEC 61131-3 soft-PLC implementations and device replacement.
Recommended
Embedded Communications Gateways
Building protocol-conversion gateways (e.g., CAN-to-Ethernet or Modbus-RTU bridges) is a classic MC68331CAG25 use case. The IMB allows the QSM SCI/UART to drive multiple RS-232/RS-485 trunks while chip-selects feed an external Ethernet controller. The 25 MHz CPU32 instruction budget comfortably supports packet routing at low-to-moderate rates. In production gateways, designers typically combine it with ENC28J60 or similar Ethernet MAC plus an external watchdog such as the SP706S.
Recommended
Industrial Test and Measurement
Test stands and bench instruments require deterministic data acquisition with reliable serial logging. The MC68331CAG25's 18 programmable I/O lines drive front-panel switches and indicator LEDs while QSM streams measurement results to a host PC. ROMless external program memory supports custom calibration tables and in-field firmware updates. The CPU32's orthogonal register set simplifies assembly-level signal processing routines for sensor linearization.
Recommended
Medical Monitoring and Diagnostic Devices
Long-lifecycle medical instrumentation such as patient monitors and infusion pump controllers value the MC68331CAG25's documented history and stable M68300 toolchain. The 25 MHz CPU32 executes RTOS-based scheduling reliably, while the IMB's QSM handles isolated serial links to sensor boards. Note that medical-grade designs require IEC 60601-1 certification paths and may favor newer parts; nonetheless the MC68331CAG25 remains in service in many certified legacy systems.
Recommended
Aerospace and UAV Avionics Modules
Sub-system avionics in UAVs and light aircraft include IMU conditioning and flight data recorders. The MC68331CAG25's compact LQFP-144 and 25 MHz performance are sufficient for sensor-fusion pre-processing and SD-card data logging through QSM SPI. The wide operating temperature range of industrial-grade silicon suits airborne thermal environments. Designers often pair it with external magnetometer and barometric ICs to keep the MCU duty cycle manageable.
Recommended
Recommended Products Summary
Engineering reference data for MC68331CAG25 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC68331CEH25 | MC68331CEH16 | MC68331CAG16 | MC68332ACEH20 | MC68331CEH20 |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 144-LQFP (20x20 mm) | 144-LQFP (20x20) | 144-LQFP (20x20) | 144-LQFP (20x20) | QFP-132 (EH) | 144-LQFP (20x20) |
| Operating Frequency | 25 MHz | 25 MHz | 16 MHz | 16 MHz | 20 MHz | 20 MHz |
| Core | CPU32 | CPU32 | CPU32 | CPU32 | CPU32 | CPU32 |
| Timer Module | GPT | GPT | GPT | GPT | TPU | GPT |
| Serial Interface | QSM (SPI + SCI) | QSM | QSM | QSM | QSM | QSM |
| Program Memory | ROMless | ROMless | ROMless | ROMless | ROMless | ROMless |
| I/O Lines | 18 | 18 | 18 | 18 | 13 | 18 |
| Lifecycle Status | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy |
Key Differentiators
- 25 MHz CPU32 is the highest frequency grade in the standard LQFP-144 M68300 family (vs MC68331CEH20)
- GPT module is more flexible than the TPU for simple PWM tasks (vs MC68332ACEH20)
- LQFP-144 package is the most pin-rich variant of the M68300 family (vs MC68332ACEH20 (QFP-132 EH))
Design Notes
The MC68331CAG25 requires clean 5.0 V power with low-impedance decoupling on every VDD/VSS pair. Place 0.1 uF X7R ceramic capacitors within 5 mm of each supply pin, supplemented by at least one bulk 10 uF tantalum per quadrant. Use a ferrite bead plus 10 uF capacitor on the analog VDDSYN rail that feeds the internal PLL/oscillator; supply noise above 50 mVpp on VDD can cause runaway of the internal state machine and clock glitches.
The 144-LQFP package has 0.5 mm pitch leads, requiring 4-layer PCB design with controlled-impedance routing for the IMB address/data bus and clock. Match trace lengths within 25 mm on CLKOUT to ADDR/DS strobes to avoid skew-induced bus errors. Provide a continuous ground plane under the LQFP to minimize inductance on the chip-to-bypass return path.
Estimated: at 25 MHz with all peripherals active the MC68331CAG25 dissipates approximately 0.8 W in a typical 5.0 V application. The 144-LQFP has theta_JA around 35 C/W on a 4-layer JEDEC test board, resulting in a 28 C rise above 70 C ambient. For sealed enclosures, verify with the manufacturer's thermal model before locking the mechanical layout.
Do not program the chip-select registers with overlapping regions or write-only bit definitions in the SIM - both cause bus contention. Always precede PLLON with a stable crystal oscillator and 10 ms reset delay. The BGND/BKPT/DSI/DSO/DSCLK debug pins must be tied to known states (typically pulled high) in production to keep the JTAG/BDM interface from spuriously halting the CPU.
Use series damping resistors (22-33 ohm) on the CLKOUT signal near the MPU to limit first-incident overshoot. Stretch out the high-current data bus edge rates with 4.7 kohm pull-ups on the SIZ0/SIZ1/RW lines if long bus stubs are present. Run the QSM SPI lines away from the IMB address bus to avoid crosstalk to sensitive serial data.
Compliance Information
Compliance certifications are not explicitly stated in the verified distributor or NXP page data; declare unknown as no source is provided. AEC-Q100 is not_applicable for this industrial part.