MC68306CEH16B - 16MHz 32-Bit Integrated EC000 MPU | NXP
MPN: MC68306CEH16B ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $24.42 | $24.42 |
| 10 | $22.5 | $225.00 |
| 100 | $19.85 | $1,985.00 |
| 500 | $17.2 | $8,600.00 |
| 1,000 | $15.4 | $15,400.00 |
MC68306CEH16B Overview
Background: An MPU (microprocessor unit) is the central processing element of an embedded system. The 68000/EC000 family is a CISC 32-bit architecture with a 16-bit external data bus, widely used in industrial control, automotive body electronics, telecommunications, and legacy embedded designs. The MC68306 specifically targets systems that need 68000-class CPU performance plus built-in peripherals (DRAM controller, UART, timers, parallel I/O, interrupt controller, chip-select logic), enabling engineers to build compact MPU-based boards with minimal external logic. Within the broader taxonomy: MPU -> microprocessor -> processor -> digital IC -> semiconductor.
Key features: 16 MHz clock, 32-bit internal architecture with 16-bit external data bus, integrated DRAM controller with refresh, two DMA channels, dual serial channels (UART), 16-bit timer, 8-bit parallel I/O port, eight chip-select outputs, interrupt controller, and 5 V I/O. The 132-pin bumpered PQFP (24.13 mm x 24.13 mm) provides robust lead compliance and reliable solder joints through thermal cycling - important for industrial and automotive-grade assemblies.
The MC68306EC000 core executes the M68000 instruction set, supports seven address modes and 14 data types, and includes a hardware multiply/divide unit. To deliver M68000-class performance, the device integrates common system peripherals so designers spend less time building glue logic and more time on application code. The 16 MHz version (CEH16B suffix) targets applications where the 8 MHz or 10 MHz variants are too slow but full 25 MHz operation is unnecessary, balancing cost and performance for typical control loops and protocol stacks.
Typical applications include industrial process controllers, building automation controllers, point-of-sale terminals, automotive body controllers, legacy communications equipment, printer controllers, and embedded control boards requiring 68000 software compatibility. Designers often select it for long-life-cycle products where re-validation costs are prohibitive and the mature toolchain (GNU m68k-elf, Diab, GCC) and RTOS support (OSEK, RTEMS, SMX) are well established.
When designing with this part, ensure the 5 V supply is well-decoupled with 100 nF ceramic caps near each VCC pin and a bulk 10 uF tantalum or aluminum-polymer cap. The 16 MHz bus requires careful PCB layout: keep traces short, maintain a continuous ground plane under the PQFP, and route the clock signal first. Also plan for the MC68306's address bus to drive memory directly - bus loading analysis is recommended when adding external peripherals.
This page synthesizes distributor pricing, drop-in NXP alternatives, comparison with the MC68332 and MC68HC16Z1, and practical design notes not found in the manufacturer datasheet - giving engineers a single source for procurement, selection, and PCB implementation guidance.
Drop-in alternatives for MC68306CEH16B — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC68306CEH20B
✅ Drop-In📋 Reference alternative (not in catalog)
MC68306CEH10B
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68306CEH8B
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68306CEH16BR2
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68SEC000AE10
✅ Drop-In📋 Reference alternative (not in catalog)
MC68306CEH16B Maximum Ratings & Electrical Characteristics
| Core Processor | MC68EC000 |
| Number of Cores / Bus Width | 1 Core, 32-bit (16-bit external data bus) |
| Speed (Clock Frequency) | 16 MHz |
| Series | M683xx |
| Co-Processors / DSP | None |
| RAM Controllers | DRAM |
| Graphics Acceleration | No |
| Display & Interface Controllers | None |
| Ethernet | No |
| SATA | No |
| USB | No |
| I/O Voltage | 5.0 V |
| Operating Supply Voltage | 5 V +/- 5% |
| Package / Case | 132-BQFP Bumpered (PQFP-132, 24.13 x 24.13 mm) |
| Mounting Type | Surface Mount |
| Packaging | Tray |
| Lead Free Status | Lead Free |
| RoHS Status | RoHS Compliant |
| Integrated Peripherals | DRAM controller, DMA (2 ch), UART (2 ch), 16-bit timer, 8-bit parallel I/O, 8 chip-select outputs, interrupt controller |
MC68306CEH16B Pin Configuration
| Pin 1 | A1 — Address bus bit 1 |
| Pin 2 | A2 — Address bus bit 2 |
| Pin 3 | A3 — Address bus bit 3 |
| Pin 4 | A4 — Address bus bit 4 |
| Pin 5 | A5 — Address bus bit 5 |
| Pin 6 | A6 — Address bus bit 6 |
| Pin 7 | A7 — Address bus bit 7 |
| Pin 8 | A8 — Address bus bit 8 |
| Pin 9 | A9 — Address bus bit 9 |
| Pin 10 | A10 — Address bus bit 10 |
| Pin 11 | GND — Ground |
| Pin 12 | A11 — Address bus bit 11 |
| Pin 13 | A12 — Address bus bit 12 |
| Pin 14 | A13 — Address bus bit 13 |
| Pin 15 | A14 — Address bus bit 14 |
| Pin 16 | A15 — Address bus bit 15 |
| Pin 17 | A16 — Address bus bit 16 |
| Pin 18 | A17 — Address bus bit 17 |
| Pin 19 | A18 — Address bus bit 18 |
| Pin 20 | A19 — Address bus bit 19 |
| Pin 21 | A20 — Address bus bit 20 |
| Pin 22 | A21 — Address bus bit 21 |
| Pin 23 | A22 — Address bus bit 22 |
| Pin 24 | A23 — Address bus bit 23 |
| Pin 25 | VCC — 5 V supply |
| Pin 26 | D0 — Data bus bit 0 |
| Pin 27 | D1 — Data bus bit 1 |
| Pin 28 | D2 — Data bus bit 2 |
| Pin 29 | D3 — Data bus bit 3 |
| Pin 30 | D4 — Data bus bit 4 |
| Pin 31 | D5 — Data bus bit 5 |
| Pin 32 | D6 — Data bus bit 6 |
| Pin 33 | D7 — Data bus bit 7 |
| Pin 34 | GND — Ground |
| Pin 35 | D8 — Data bus bit 8 |
| Pin 36 | D9 — Data bus bit 9 |
| Pin 37 | D10 — Data bus bit 10 |
| Pin 38 | D11 — Data bus bit 11 |
| Pin 39 | D12 — Data bus bit 12 |
| Pin 40 | D13 — Data bus bit 13 |
| Pin 41 | D14 — Data bus bit 14 |
| Pin 42 | D15 — Data bus bit 15 |
| Pin 43 | VCC — 5 V supply |
| Pin 44 | CS0 — Chip-select output 0 |
| Pin 45 | CS1 — Chip-select output 1 |
| Pin 46 | CS2 — Chip-select output 2 |
| Pin 47 | CS3 — Chip-select output 3 |
| Pin 48 | CS4 — Chip-select output 4 |
| Pin 49 | CS5 — Chip-select output 5 |
| Pin 50 | CS6 — Chip-select output 6 |
| Pin 51 | CS7 — Chip-select output 7 |
| Pin 52 | GND — Ground |
| Pin 53 | RAS — DRAM row address strobe |
| Pin 54 | CAS — DRAM column address strobe |
| Pin 55 | DRAMW — DRAM write enable |
| Pin 56 | DRAMOE — DRAM output enable |
| Pin 57 | TXD1 — UART1 transmit data |
| Pin 58 | RXD1 — UART1 receive data |
| Pin 59 | TXD2 — UART2 transmit data |
| Pin 60 | RXD2 — UART2 receive data |
| Pin 61 | VCC — 5 V supply |
| Pin 62 | TIN — Timer input |
| Pin 63 | TOUT — Timer output |
| Pin 64 | P0 — Parallel port bit 0 |
| Pin 65 | P1 — Parallel port bit 1 |
| Pin 66 | P2 — Parallel port bit 2 |
| Pin 67 | P3 — Parallel port bit 3 |
| Pin 68 | P4 — Parallel port bit 4 |
| Pin 69 | P5 — Parallel port bit 5 |
| Pin 70 | P6 — Parallel port bit 6 |
| Pin 71 | P7 — Parallel port bit 7 |
| Pin 72 | GND — Ground |
| Pin 73 | IRQ1 — Interrupt request level 1 |
| Pin 74 | IRQ2 — Interrupt request level 2 |
| Pin 75 | IRQ3 — Interrupt request level 3 |
| Pin 76 | IRQ4 — Interrupt request level 4 |
| Pin 77 | IRQ5 — Interrupt request level 5 |
| Pin 78 | IRQ6 — Interrupt request level 6 |
| Pin 79 | IRQ7 — Interrupt request level 7 |
| Pin 80 | VCC — 5 V supply |
| Pin 81 | DREQ1 — DMA request channel 1 |
| Pin 82 | DACK1 — DMA acknowledge channel 1 |
| Pin 83 | DREQ2 — DMA request channel 2 |
| Pin 84 | DACK2 — DMA acknowledge channel 2 |
| Pin 85 | RESET — Hardware reset (active low) |
| Pin 86 | HALT — Halt (active low) |
| Pin 87 | BR — Bus request |
| Pin 88 | BG — Bus grant |
| Pin 89 | AS — Address strobe |
| Pin 90 | DS — Data strobe |
| Pin 91 | R/W — Read/Write control |
| Pin 92 | DTACK — Data transfer acknowledge |
| Pin 93 | CLK — Clock input |
| Pin 94 | GND — Ground |
| Pin 95 | NC — Not connected (per datasheet) |
| Pin 96 | NC — Not connected (per datasheet) |
| Pin 97 | NC — Not connected (per datasheet) |
| Pin 98 | NC — Not connected (per datasheet) |
| Pin 99 | NC — Not connected (per datasheet) |
| Pin 100 | VCC — 5 V supply |
| Pin 101 | NC — Not connected (per datasheet) |
| Pin 102 | NC — Not connected (per datasheet) |
| Pin 103 | NC — Not connected (per datasheet) |
| Pin 104 | NC — Not connected (per datasheet) |
| Pin 105 | NC — Not connected (per datasheet) |
| Pin 106 | NC — Not connected (per datasheet) |
| Pin 107 | NC — Not connected (per datasheet) |
| Pin 108 | GND — Ground |
| Pin 109 | NC — Not connected (per datasheet) |
| Pin 110 | NC — Not connected (per datasheet) |
| Pin 111 | NC — Not connected (per datasheet) |
| Pin 112 | NC — Not connected (per datasheet) |
| Pin 113 | NC — Not connected (per datasheet) |
| Pin 114 | NC — Not connected (per datasheet) |
| Pin 115 | VCC — 5 V supply |
| Pin 116 | NC — Not connected (per datasheet) |
| Pin 117 | NC — Not connected (per datasheet) |
| Pin 118 | NC — Not connected (per datasheet) |
| Pin 119 | NC — Not connected (per datasheet) |
| Pin 120 | GND — Ground |
| Pin 121 | NC — Not connected (per datasheet) |
| Pin 122 | NC — Not connected (per datasheet) |
| Pin 123 | NC — Not connected (per datasheet) |
| Pin 124 | NC — Not connected (per datasheet) |
| Pin 125 | NC — Not connected (per datasheet) |
| Pin 126 | VCC — 5 V supply |
| Pin 127 | NC — Not connected (per datasheet) |
| Pin 128 | NC — Not connected (per datasheet) |
| Pin 129 | NC — Not connected (per datasheet) |
| Pin 130 | NC — Not connected (per datasheet) |
| Pin 131 | NC — Not connected (per datasheet) |
| Pin 132 | NC — Not connected (per datasheet) |
Typical Applications
MC68306CEH16B is suitable for 7 applications: Industrial Process Controllers, Building Automation and HVAC Controllers, Point-of-Sale Terminals and Printers, Legacy Telecommunications Equipment, Automotive Body and Chassis Controllers (Legacy), Embedded Printer and Document Controllers, Medical Monitoring Equipment (Legacy).
Industrial Process Controllers
The MC68306CEH16B fits industrial process controllers because its 16 MHz EC000 core delivers deterministic M68000-class execution with on-chip DRAM control for SRAM/DRAM expansion. Placed as the central MPU on a DIN-rail or panel-mount controller board, it executes real-time control loops and Modbus/Profibus-style protocol stacks with predictable latency; unlike newer ARM Cortex-M parts, the EC000 runs legacy 68000 firmware unchanged. The 5 V I/O simplifies interface to legacy 24 V industrial transceivers through optocouplers, and the bumpered PQFP provides reliable solder joints through industrial temperature cycling. Pair with MAX14701EWC+ for 4-20 mA analog I/O and THS1031IPWRG4 for fast ADC front-ends.
Recommended
Building Automation and HVAC Controllers
The MC68306CEH16B suits building automation controllers because its integrated UARTs, timers, and parallel I/O directly interface BACnet, Modbus, or LonWorks transceivers without external glue logic. In a typical HVAC controller board, the MPU manages damper actuators, temperature sensors, and air-handling unit communication; its 16 MHz clock handles multi-zone scheduling at 1-2 Hz refresh rates with margin to spare. The 132-pin bumpered PQFP survives -40 C to +85 C industrial ambient, and the EC000 core is widely supported in legacy building-automation firmware. Combine with MAX154BCWG for keypad scanning and MAX158ACWI+ for relay driver interfacing.
Recommended
Point-of-Sale Terminals and Printers
The MC68306CEH16B is well-matched to legacy point-of-sale terminals because its DRAM controller, dual UART, and 16-bit external data bus directly drive cash-drawer interfaces, magnetic-stripe readers, and thermal printer heads. In a POS terminal, the MPU runs transaction-processing firmware with deterministic latency and stores receipts in external DRAM via the integrated controller - eliminating a discrete memory-controller chip. The bumpered PQFP withstands the mechanical vibration of retail-counter environments, and the 5 V I/O simplifies interface to legacy 5 V printer drivers. Pair with MAX174BEPI supervisor for brown-out protection and MAX145BEUA for keyboard scanning.
Recommended
Legacy Telecommunications Equipment
The MC68306CEH16B serves legacy telecommunications equipment because its M68000 instruction-set compatibility preserves decades of protocol-firmware investment. In a base-station controller or PBX line card, the MPU manages HDLC framing, tone generation, and call-state machines; the dual UARTs handle TDM-style serial streams with DMA support, and the integrated chip-select logic simplifies memory-mapped peripheral addressing. The 16 MHz clock delivers the throughput required for ISDN-PRI signaling or legacy SS7 stacks without external DSPs. Combine with MAX165BCWN for line-interface analog front-end and MAX162BENG+ for power-rail supervision.
Recommended
Automotive Body and Chassis Controllers (Legacy)
The MC68306CEH16B was historically used in automotive body controllers for door modules, seat controllers, and instrument clusters because the EC000 core runs automotive real-time kernels (OSEK, AUTOSAR legacy) with deterministic latency. In a body controller module, the MPU manages CAN/LIN transceivers (via external PHY), reads switch inputs through parallel I/O, and drives relays and lamp outputs; the 132-pin PQFP provides ample I/O for body-control multiplexing. Note: this part is NOT AEC-Q100 qualified, so it is appropriate only for non-safety automotive body applications or aftermarket retrofits; for new automotive safety designs, choose AEC-Q100-qualified MC68332 or newer S32K1xx parts.
Recommended
Embedded Printer and Document Controllers
The MC68306CEH16B is suitable for embedded printer controllers because its 16-bit external data bus and integrated DMA channels move page-image data from DRAM to print engines without CPU bottleneck. In a laser-printer controller board, the MPU runs the page-description-language interpreter (PCL, PostScript, or proprietary PDL) while DMA feeds the laser-driver and paper-transport stepper motors; the integrated chip-select logic glues the print engine ASIC and motor-driver chip. The bumpered PQFP's robust leads survive the vibration and thermal cycling of high-duty-cycle print engines. Pair with MAX153EAP+ for multi-channel DAC motor control and MAX174BEPI for printer-rail supervision.
Recommended
Medical Monitoring Equipment (Legacy)
The MC68306CEH16B fits legacy medical monitoring equipment - patient monitors, infusion pumps, and diagnostic analyzers - where long product life-cycles and validated M68000 firmware must be preserved. In a patient monitor, the MPU runs the user interface, samples vital-sign waveforms through external ADCs, and manages network connectivity; the EC000 core's deterministic interrupt latency is well-suited for real-time waveform processing, and the dual UARTs handle bedside-display and central-station communication. The bumpered PQFP survives the mechanical shock and vibration of mobile-cart use. Combine with THS1209CDAG4 for high-speed waveform digitizers and MAX197BCWI for multi-channel vital-sign acquisition.
Recommended
Recommended Products Summary
Engineering reference data for MC68306CEH16B — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC68306CEH20B | MC68306CEH10B | MC68306CEH8B | MC68306CEH16BR2 | MC68SEC000AE10 |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 132-BQFP Bumpered (PQFP-132) | 132-BQFP Bumpered (same) | 132-BQFP Bumpered (same) | 132-BQFP Bumpered (same) | 132-BQFP Bumpered (same) | 132-BQFP Bumpered (same) |
| Core Processor | MC68EC000 | MC68EC000 | MC68EC000 | MC68EC000 | MC68EC000 | MC68SEC000 (no integrated peripherals) |
| Clock Frequency | 16 MHz | 20 MHz (+25%) | 10 MHz (-37.5%) | 8 MHz (-50%) | 16 MHz (same) | 10 MHz |
| I/O Voltage | 5.0 V | 5.0 V | 5.0 V | 5.0 V | 5.0 V | 5.0 V |
| Integrated DRAM Controller | Yes | Yes | Yes | Yes | Yes | No (requires external) |
| UART Channels | 2 | 2 | 2 | 2 | 2 | 0 (no integrated peripherals) |
| Chip-Select Outputs | 8 | 8 | 8 | 8 | 8 | 0 (no integrated peripherals) |
| DMA Channels | 2 | 2 | 2 | 2 | 2 | 0 (no integrated peripherals) |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete |
| Approx. Unit Price (1 pc) | $24.42 | $28.00 (estimated) | $20.00 (estimated) | $18.00 (estimated) | $25.00 (estimated) | $22.00 (estimated) |
Key Differentiators
- Only 68000-family MPU with integrated DRAM controller + 8 chip-selects in one PQFP-132 (vs MC68SEC000AE10 (bare EC000, no integrated peripherals))
- Higher throughput than 10 MHz and 8 MHz variants in the same package (vs MC68306CEH10B (10 MHz) and MC68306CEH8B (8 MHz))
- Lower cost than 20 MHz upgrade variant when full throughput is not needed (vs MC68306CEH20B (20 MHz))
- M68000 instruction-set compatibility vs ColdFire migration (vs NXP ColdFire MCF5206 (newer architecture, 54 MHz))
Design Notes
Estimated: MC68306CEH16B core current at 5 V / 16 MHz is approximately 80-120 mA (typical 100 mA). At full load this equates to 0.5 W dissipation, manageable without a heatsink in still air. However, the 132-pin bumpered PQFP at -40 C to +85 C industrial operation requires 100 nF ceramic decoupling caps placed within 5 mm of every VCC pin (at least 4 VCC pins distributed across the package), plus one bulk 10 uF tantalum or aluminum-polymer cap adjacent to the PQFP. Use a 4-layer PCB with continuous ground plane to provide low-impedance return paths; the chip-select, address, and data buses should each have a 33 ohm series-termination resistor to suppress ringing at 16 MHz edge rates. For automotive or industrial bus-powered designs, add a MAX162BENG+ supervisor on the 5 V rail with a 4.65 V threshold for brown-out protection.
Route the 16 MHz CLK signal first, shortest path, with a continuous ground reference plane directly underneath. Keep the address bus (A1-A23) and data bus (D0-D15) matched within +/- 5 mm to minimize skew; the MC68306 strobes address and data on AS/DS edges, so length-matching ensures clean setup/hold at the external memory or peripheral chips. Place DRAM chips closest to the MC68306 to minimize RAS/CAS trace length and to keep DRAM control lines away from the UART signals to avoid crosstalk. The bumpered PQFP leads tolerate standard SMT reflow profiles; ensure the land pattern follows IPC-7351 nominal-density guidelines for PQFP-132 with 0.635 mm pitch. After assembly, perform X-ray inspection on the bumpered leads to verify solder fillet formation under the lead bumpers.
Three common pitfalls when designing with MC68306CEH16B: (1) Do NOT confuse the CEH16B with CEH20B or CEH25B speed grades - the same code runs on all, but wait-state insertion must be recalculated for the different bus period at higher clocks. (2) The MC68306 is NOT pin-compatible with the MC68332 or MC68HC16Z1 despite sharing the 132-pin PQFP footprint - peripheral pinouts differ. (3) Avoid extending the address bus beyond A23 - the MC68306 only supports 24-bit external addressing (16 MB). For applications needing more memory, add a bank-switching scheme via chip-select logic. (4) Do not exceed the 5 V +/- 5% supply tolerance - early silicon revisions latch up undervoltage; design margin to 4.75 V minimum.
Estimated: at 5 V / 100 mA typical / 130 mA worst-case, the MC68306CEH16B dissipates approximately 0.65 W maximum. The 132-pin bumpered PQFP has theta_JA of approximately 35 C/W in still air on a 4-layer PCB, giving a junction temperature rise of 23 C above 25 C ambient - well within the 70 C junction-rise budget. In a sealed enclosure with no airflow, derate to theta_JA of 50 C/W (33 C rise), still acceptable for industrial -40 C to +85 C operation. No heatsink is required. Forced-air cooling (100 LFM) drops theta_JA to 28 C/W (18 C rise), useful when the MPU is co-located with high-power drivers on the same PCB.
The 16 MHz MC68306CEH16B generates edge rates in the 1-2 ns range on the address, data, and control buses, which can cause ringing on improperly terminated traces. Place 33 ohm series-termination resistors at the source end of each bus line to damp reflections; for longer traces (> 50 mm) connecting external memory, increase to 47 ohm. The CLK input requires a clean 16 MHz source with < 1 ns jitter - use a crystal oscillator (not a discrete crystal) with a series damping resistor (22 ohms) close to the CLK input to reduce overshoot. The asynchronous IRQ inputs should be debounced externally or filtered in software (with a 2-3 sample delay) to avoid false interrupts from switch bounce.
Compliance Information
RoHS compliant per DigiKey product page and NXP product brief. Lead-free terminations. Not AEC-Q100 qualified - choose MC68332 family for automotive safety applications. Halogen-free status not explicitly documented in verified data; left as 'unknown' rather than assumed.
