MC68302CEH16C - 16MHz M68300 Multiprotocol Comm Processor | NXP
MPN: MC68302CEH16C ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $90.76 | $90.76 |
| 10 | $81.5 | $815.00 |
| 100 | $68.25 | $6,825.00 |
| 500 | $58.4 | $29,200.00 |
| 1,000 | $49.9 | $49,900.00 |
MC68302CEH16C Overview
An M68300 (formerly 683xx) multiprotocol communications processor is a highly integrated System-on-Chip that merges the M68k CPU core with serial channel hardware, timers, and DMA to offload protocol handling from external logic. The MC68302 family sits in the M68000 product hierarchy between simpler 68k microcontrollers (MC68332) and higher-performance 68k networking parts (MC68360), making it a sweet spot for cost-sensitive voice/data routing and terminal equipment. This background explains the part's continued presence in legacy telecommunication, ISDN, and industrial control designs even decades after introduction.
The MC68302CEH16C runs at 16MHz with a 16-bit data bus, integrates up to three independent serial communication controllers supporting HDLC, UART, BISYNC, and transparent modes, plus a 7-channel DMA controller, three parallel I/O ports, and two independent timers. The 132-pin PQFP-132 (46x46 mm) package is a plastic quad flat pack designed for surface-mount assembly on telecom backplanes and VME-based hardware. Operating voltage spans 4.5V to 5.5V and the device is rated for the industrial temperature range of 0C to +70C.
This part was originally designed to reduce component count in routers, bridges, X.25 PADs, frame relay access devices, and ISDN terminal adapters by collapsing what was previously a CPU plus separate serial controller chip plus DMA chip into one silicon die. The architecture closely couples the 68000 core to the on-chip peripheral modules via dedicated interrupt and bus-arbiter logic so that protocol engines can move bytes with minimal CPU intervention. Because the Serial Communication Controllers (SCCs) handle framing in hardware, the core is free to execute higher-layer stacks.
Typical applications include remote access concentrators, industrial serial gateways, X.25 packet assemblers/disassemblers, ISDN terminal adapters, and legacy telecom line cards. Engineers also deploy this part in long-life industrial control and metering platforms where it is favored for its deterministic behavior and extensive firmware ecosystem built over decades.
When designing with the MC68302CEH16C, ensure a robust 5V rail (the device is intolerant of 3.3V supply) and provide bulk decoupling on each VDD/VSS pair. The 132-pin PQFP-132 footprint demands a 4-layer board with via-in-pad escape for clean signal integrity on the parallel port lines; allocate adequate cooling area since the 16MHz core dissipates measurable power under continuous bus activity.
This page synthesizes cross-reference alternatives, distributor pricing, and form-fit-function design notes for engineers seeking to source or replace the MC68302CEH16C in legacy and long-lifecycle platforms.
Drop-in alternatives for MC68302CEH16C — 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 MC68302CEH16C (same form factor and footprint) — differing in Data Bus Width, Mounting Type, Maximum Clock Frequency, Package, Core.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC68302EH16C
✅ Drop-In✓ In Stock
$17.1 / Unit
View Datasheet →MC68302CEH20C
✅ Drop-In📋 Reference alternative (not in catalog)
MC68302CFC16C
✅ Drop-In📋 Reference alternative (not in catalog)
MC68302CRC20C
✅ Drop-In✓ In Stock
$47.8 / Unit
View Datasheet →MC68302EH20C
✅ Drop-In✓ In Stock
$19.85 / Unit
View Datasheet →MC68302CEH16C Maximum Ratings & Electrical Characteristics
| Core Architecture | M68000 / M683xx |
| Core Count | 1 |
| Data Bus Width | 8/16-Bit |
| Maximum Clock Frequency | 16 MHz |
| Operating Supply Voltage | 4.5 V to 5.5 V |
| Package | 132-PQFP (46 x 46 mm) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | 0 C to +70 C |
| On-Chip Serial Communication Controllers | 3 SCC channels |
| On-Chip DMA Channels | 7 |
| On-Chip Timers | 2 |
| Parallel I/O Ports | 3 |
| Series | M683xx |
| Instruction Set | M68k (MC68000/MC68008 compatible) |
| RoHS Status | unknown |
| Lead-Free | unknown |
| MSL Level | 3 (168 hours) |
MC68302CEH16C 132-pqfp (46 x 46 mm) Pin Configuration Guide
Pin configuration for MC68302CEH16C (132-pqfp (46 x 46 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 MC68302CEH16C.
Refer to the datasheet for full pin configuration.
Typical Applications
MC68302CEH16C is suitable for 6 applications: X.25 Packet Assembler/Disassembler (PAD), ISDN Terminal Adapter, Industrial Serial Gateway, LAN-to-WAN Router Line Card, Frame Relay Access Device (FRAD), Legacy Telecom Line Card.
X.25 Packet Assembler/Disassembler (PAD)
The MC68302CEH16C's three hardware SCCs directly support HDLC framing for X.25 packet assembly, while the integrated DMA offloads buffer management from the 68000 core. Designers typically place this part on a 5V serial line card with 256-512KB SRAM and a single EPROM/Flash; the 16MHz clock processes X.25 layer-2/3 at full V.24 rates with minimal CPU overhead, keeping BOM cost low versus discrete CPU plus SCC plus DMA implementations.
Recommended
ISDN Terminal Adapter
The MC68302CEH16C's hardware HDLC channels handle the D-channel signaling and B-channel data streams of an ISDN BRI link (2B+D) without CPU intervention. The 16MHz 68000 core executes the upper-layer LAPD state machine and rate adaptation logic while SCCs frame the bit streams and DMA moves bytes between memory and the transceivers, per the NXP reference design. The result is a compact 5V card that fits in a basic-rate terminal with a small external flash footprint.
Recommended
Industrial Serial Gateway
For factory-floor RS-232/RS-485 to Ethernet gateways, the MC68302CEH16C delivers deterministic serial-channel handling through three independent SCCs and seven DMA channels, allowing each UART port to run at full line rate without frame loss. The 16MHz 68000 executes the protocol conversion stack while hardware handles framing, keeping latency under 1ms per byte. Its 0C to +70C commercial temperature range suits indoor control cabinets; for harsher environments, pair with an industrial-screened -40C-to-+85C qualified lot.
Recommended
LAN-to-WAN Router Line Card
Legacy routers and bridges in VME-based chassis use the MC68302CEH16C to terminate WAN serial links via its HDLC-capable SCCs while the 68000 core runs IP routing tables and the management interface. The 16MHz clock balances throughput against cost on T1/E1 or sub-T1 link aggregation cards; its 132-PQFP footprint fits comfortably on Eurocard-sized PCBs with on-board bus transceivers. Five-volt operation simplifies the power tree in telecom backplane designs.
Recommended
Frame Relay Access Device (FRAD)
The MC68302CEH16C is a classic FRAD-on-a-chip, with each SCC terminating one or more frame relay PVCs using hardware HDLC and direct DMA into packet buffers. The 68000 core handles PVC management, LMI, and encapsulation (FRF.12) while the DMA engine keeps the serial channel rings full. A 5V linear regulator and discrete RS-232 transceivers complete a board layout of roughly 100x100 mm including the 132-PQFP footprint and standard SRAM/Flash subsystem.
Recommended
Legacy Telecom Line Card
Central-office voice and data line cards historically used the MC68302CEH16C as a per-channel control processor, leveraging its hardware HDLC for signaling and its timers for pulse metering. The 16MHz 68k core runs the per-line state machine while the DMA channels steer DSP/RTP buffers to external DSPs or codecs. Its mature firmware ecosystem and long-life availability through authorized distributors make it a long-tail preferred part for telecom refresh projects.
Recommended
Recommended Products Summary
Engineering reference data for MC68302CEH16C — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC68302EH16C | MC68302CEH20C | MC68302CFC16C | MC68302CRC20C | MC68302EH20C |
|---|---|---|---|---|---|---|
| Package | 132-PQFP (46x46 mm) | 132-PQFP (46x46 mm) | 132-PQFP (46x46 mm) | 132-PQFP (46x46 mm) | 132-PQFP (46x46 mm) | 132-PQFP (46x46 mm) |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Maximum Clock Frequency | 16 MHz | 16 MHz (0%) | 20 MHz (+25%) | 16 MHz (0%) | 20 MHz (+25%) | 20 MHz (+25%) |
| Operating Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| Serial Communication Controllers | 3 | 3 | 3 | 3 | 3 | 3 |
| DMA Channels | 7 | 7 | 7 | 7 | 7 | 7 |
| Core | M68000/M68k | M68000/M68k | M68000/M68k | M68000/M68k | M68000/M68k | M68000/M68k |
| Series | M683xx | M683xx | M683xx | M683xx | M683xx | M683xx |
| Lifecycle Status | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy |
Key Differentiators
- Last Time Buy status calls for sourcing strategy (vs MC68302EH16C)
- 20MHz speed-grade upgrade path on same footprint (vs MC68302CEH20C)
- Higher-end QUICC successor for UTOPIA/ATM workloads (vs MC68360CAI25L)
Design Notes
The MC68302CEH16C requires a robust 5V rail because the device is not 3.3V-tolerant on any VDD pin; use an LDO or DC-DC regulator that delivers at least 200 mA continuous per the NXP datasheet, with bulk decoupling (10uF + 100uF) on each VDD/VSS pair. Per the hardware design guide, place the regulator within 25 mm of the MPU's VDD pins to minimize input voltage transient excursions during DMA peak load.
The 132-PQFP (46x46 mm) package has a 0.635 mm lead pitch and demands a 4-layer PCB with via-in-pad escape for the parallel port bus lines, per NXP reference designs. Maintain a continuous ground plane beneath the part and route all high-speed address lines over the unbroken ground reference; this prevents bus contention and signal-integrity issues when reading external memory at full 16MHz.
Do not assume the Watchdog Timer is enabled by default - confirm the WD pin configuration during board bring-up, otherwise bus-locks will not be recovered. Also, ensure the RESET pin is held low for at least 100 master clock cycles after VDD reaches the 4.5V minimum, since premature exit from reset can lock the M68k pipeline. These pitfalls are documented in the NXP MC68302 errata sheet.
Estimated: at 16MHz with all three SCCs and seven DMA channels active, the MC68302CEH16C dissipates roughly 600-800 mW into the 132-PQFP package. Since the PQFP-132 has no exposed thermal pad, mount the part with at least 25 cm^2 of 1 oz copper pour directly under and around the package on top and bottom layers to keep junction rise below 15 C at ambient 25 C.
Compliance Information
RoHS/REACH/lead-free status was not present in the available datasheet extract; verify on the specific lot's certificate of conformance before placing into a RoHS-restricted assembly. AEC-Q100 not applicable for this commercial-temperature MPU.
