MC68302AG25C - 25MHz M683xx Integrated Comm Processor | NXP
MPN: MC68302AG25C ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $28.5 | $28.50 |
| 10 | $25.2 | $252.00 |
| 100 | $22 | $2,200.00 |
| 500 | $18.8 | $9,400.00 |
| 1,000 | $16.4 | $16,400.00 |
MC68302AG25C Overview
An integrated communications processor (ICP) is a category of embedded microprocessor that tightly couples a CPU core with dedicated serial-channel and DMA hardware on the same silicon die. In the system hierarchy, the MC68302 sits above generic microcontrollers (which typically lack multi-protocol serial engines) and below full network processors (NPUs) that integrate dedicated MAC-layer offload. This integration reduces external component count in embedded networking designs by replacing discrete UART, DMA, and interrupt controller chips with on-die logic.
Key features of the MC68302AG25C include a 25 MHz maximum internal clock, 8/16-bit external data bus width, separate 32-bit M68000 internal architecture, programmable chip-select outputs, dual-port RAM for descriptor management, and a watchdog timer. The device operates from a single 5 V supply and is rated for the commercial temperature range of 0C to 70C.
Architecturally, the MC68302 separates control-plane and data-plane tasks by offloading DMA and serial-protocol handling to the CPM block. Each SCC supports protocols such as HDLC, UART, BISYNC, and transparent mode, while the IDMA controller supports linked-list descriptor operation. This dual-engine partitioning enables sustained serial throughput even when the CPU is servicing application-layer logic.
Typical applications include ISDN terminal adapters, low-end routers and bridges, industrial serial concentrators, factory automation gateways, and legacy telecom line cards. Its wide protocol support makes it especially suited to multi-protocol serial multiplexing in industrial and telecom systems.
When designing with the MC68302AG25C, ensure that the host PCB provides a 25 MHz oscillator with adequate stability, and that the system memory map is configured via the base address registers before any peripheral initialization. Improper bus-cycle termination can cause intermittent DMA underruns under heavy SCC load.
This page synthesizes distributor availability, drop-in alternatives within the M68302 family, and practical design considerations not consolidated in the original Motorola/Freescale datasheet.
Drop-in alternatives for MC68302AG25C — 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 MC68302AG25C (same form factor and footprint) — differing in Core Architecture, Address Bus Width, DMA Channels, Data Bus Width, Maximum Clock Frequency.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC68302FC25C
✅ Drop-In📋 Reference alternative (not in catalog)
MC68302CFC25C
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68302AG16C
✅ Drop-In✓ In Stock
$13.55 / Unit
View Datasheet →MC68302FC20C
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68302AG20C
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$54.1 / Unit
View Datasheet →MC68302AG25C Maximum Ratings & Electrical Characteristics
| Core Processor | M68000 |
| Core Architecture | M683xx |
| Number of Cores | 1 |
| Data Bus Width | 8/16 bit |
| Maximum Clock Frequency | 25 MHz |
| Internal Architecture | 32-bit |
| Supply Voltage | 5 V |
| Operating Temperature | 0C to 70C |
| Package / Case | 144-LQFP (20x20 mm) |
| Mounting Type | Surface Mount |
| Serial Communication Controllers (SCC) | 3 |
| Serial Management Controllers (SMC) | 2 |
| DMA Channels (IDMA) | 2 |
| Timers | 2 x 16-bit |
| Watchdog Timer | Yes |
| Programmable Chip Selects | Yes |
| Dual-Port RAM | Yes (for descriptors) |
| RoHS Status | Compliant (factory statement) |
MC68302AG25C 144-lqfp (20x20 mm) Pin Configuration Guide
Pin configuration for MC68302AG25C (144-lqfp (20x20 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 MC68302AG25C.
Refer to the datasheet for full pin configuration.
Typical Applications
MC68302AG25C is suitable for 6 applications: ISDN Terminal Adapter, Low-End Router/Bridge, Industrial Serial Concentrator, Factory Automation Gateway, Legacy Telecom Line Card, POS Terminal / Embedded Controller.
ISDN Terminal Adapter
The MC68302AG25C fits ISDN terminal adapters because its three SCCs support HDLC/SDLC framing at sustained bit rates well above ISDN BRI's 144 kbps per B-channel. With 25 MHz core clock and on-chip IDMA, the CPM block can offload framing and DMA tasks so the CPU handles only the application layer. The 144-LQFP package supports the small form factor typical of desktop ISDN adapters.
Recommended
Low-End Router/Bridge
The MC68302AG25C fits low-end router/bridge designs because its three SCCs map naturally to LAN/WAN/modem ports and the IDMA engine handles packet transfer to/from external buffer memory without CPU intervention. At 25 MHz the M68000 core can route small frames at wire rate on low-speed serial links. The 5 V single supply and 144-LQFP package suit industrial router hardware where reliability matters more than absolute throughput.
Recommended
Industrial Serial Concentrator
The MC68302AG25C fits industrial serial concentrators that aggregate multiple RS-232/RS-485 links because each SCC independently supports UART framing and the IDMA engine links descriptors for back-to-back reception. At 25 MHz the device can manage five simultaneous serial channels (3 SCC + 2 SMC) with low CPU overhead. The commercial 0-70C range suits factory-floor cabinets; the 5 V supply simplifies power design.
Recommended
Factory Automation Gateway
The MC68302AG25C fits factory automation gateways that bridge fieldbus protocols (Profibus, Modbus, etc.) to Ethernet or higher-speed backbones because its multi-protocol SCCs can be configured to support the framing of each fieldbus variant. The on-chip watchdog timer and programmable chip selects simplify interface logic to glue peripherals. Designers favor the 144-LQFP package for its industrial-grade assembly compatibility.
Recommended
Legacy Telecom Line Card
The MC68302AG25C fits legacy telecom line cards where HDLC channels terminate T1/E1 spans because each SCC handles full HDLC bit stuffing and CRC generation in hardware at 1.544/2.048 Mbps. The 25 MHz core can supervise per-channel maintenance without taxing CPU bandwidth. Its 5 V supply aligns with legacy backplane power designs still deployed in central-office line-card shelves.
Recommended
POS Terminal / Embedded Controller
The MC68302AG25C fits point-of-sale terminals and embedded controllers that require multiple UART peripherals (printer, scanner, EFT modem) because its five independent serial channels (3 SCC + 2 SMC) eliminate the need for an external UART-expansion chip. The M68000 core executes terminal-control firmware comfortably at 25 MHz. The 144-LQFP package meets surface-mount manufacturing cost targets.
Recommended
Recommended Products Summary
Engineering reference data for MC68302AG25C — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC68302FC25C | MC68302CFC25C | MC68302AG16C | MC68302FC20C | MC68302AG20C |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors (formerly Freescale) | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 144-LQFP (20x20) | 144-LQFP (20x20) - same | 144-LQFP (20x20) - same | 144-LQFP (20x20) - same | 144-LQFP (20x20) - same | 144-LQFP (20x20) - same |
| Maximum Clock Frequency | 25 MHz | 25 MHz | 25 MHz | 16 MHz (-36%) | 20 MHz (-20%) | 20 MHz (-20%) |
| Core Architecture | M68000 | M68000 | M68000 | M68000 | M68000 | M68000 |
| Data Bus Width | 8/16 bit | 8/16 bit | 8/16 bit | 8/16 bit | 8/16 bit | 8/16 bit |
| Operating Temperature | 0C to 70C (commercial) | 0C to 70C | -40C to 85C (industrial CF grade) | 0C to 70C | 0C to 70C | 0C to 70C |
| SCC Count | 3 | 3 | 3 | 3 | 3 | 3 |
| Supply Voltage | 5 V | 5 V | 5 V | 5 V | 5 V | 5 V |
Key Differentiators
- Faster clock than 16 MHz / 20 MHz M68302 grades (vs MC68302AG16C)
- Industrial temperature variant available in same package (vs MC68302CFC25C)
- Three independent SCCs vs MC68332's QSM (vs MC68332ACAG25)
Design Notes
Estimated: The MC68302AG25C draws approximately 200-300 mA from a single 5 V supply at 25 MHz. Provide a 10 uF tantalum bulk capacitor near the VCC pins and 0.1 uF ceramic decoupling on each VCC pin pair. Unlike low-voltage ARM/ColdFire parts, no separate core or PLL rail is required.
Estimated: At continuous 25 MHz with all SCCs active, power dissipation is roughly 1.0-1.5 W. The 144-LQFP package thermal resistance theta_JA is approximately 35 C/W on a standard 4-layer JEDEC test board, yielding a junction temperature rise of 35-50C above ambient. For continuous full-load operation in cabinets exceeding 50C ambient, ensure adequate airflow or attach a small heatsink.
Do not exceed 5.5 V on any VCC pin or 6.5 V absolute maximum on input pins - the M68000 core is a 5 V part and lacks modern ESD tolerance. Ensure the external 25 MHz oscillator meets the datasheet AC electrical characteristics (rise/fall time under 5 ns). Improper bus-cycle termination can cause intermittent DMA underruns under heavy SCC load - terminate bus signals per the application note recommendations.
The external data bus operates at 8/16-bit width with synchronous clocking at 25 MHz. Trace lengths on the address/data bus should be matched to within 25 mm to avoid bus contention during read/write cycles. Add 33 ohm series termination on the bus signals if routing exceeds 50 mm, especially on backplane designs where multiple loads are present.
Compliance Information
RoHS compliance per NXP factory statements. Not AEC-Q100 qualified (this is a telecom/networking MPU, not automotive). For automotive-grade networking processors, consider MCF52235 or similar ColdFire automotive parts.
