MC68882CRC20A - 32-bit Floating-Point Coprocessor, 20 MHz | NXP
MPN: MC68882CRC20A ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $54.76 | $54.76 |
| 10 | $49.28 | $492.80 |
| 100 | $43.81 | $4,381.00 |
| 250 | $39.5 | $9,875.00 |
| 500 | $35.2 | $17,600.00 |
MC68882CRC20A Overview
A floating-point coprocessor (FPU) is a specialized processor that offloads IEEE 754 floating-point arithmetic from the main CPU, executing add, subtract, multiply, divide, square root, and transcendental operations in hardware. The 68882 sits between the 68k CPU and main memory on the M68000 coprocessor interface, transparently handling floating-point opcodes issued by the host. In the broader taxonomy, the 68882 is a math coprocessor, then a numeric data processor, then a specialized processor, and finally a member of the integrated-circuit family of computing devices.
Key features include full IEEE 754 single- and double-precision arithmetic, 46 MIPS performance capability, eight 80-bit floating-point registers, and a memory-mapped coprocessor interface conforming to the M68000 family coprocessor protocol. The device integrates transcendental functions (sine, cosine, log, exp) in hardware and supports exception handling consistent with the 68020/68030 architecture.
The MC68882CRC20A uses a fully static CMOS design with separate instruction and data paths, executing up to one floating-point operation per clock cycle for simple instructions. Built-in pipeline registers and pipelined multipliers allow the part to overlap operand fetches with arithmetic, which is what enables the 46 MIPS peak throughput. The device is software-compatible with the earlier MC68881 FPU.
Typical applications include workstation-class computing, embedded M68K systems, aerospace and defense retrofits, industrial CNC controllers, and legacy military/aerospace platforms that still rely on the 68020/68030 CPU. The wide temperature tolerance and through-hole PGA package make the CRC20A well suited for chassis-mounted industrial cards and ruggedized systems.
When designing with this part, ensure the coprocessor interface is correctly terminated on the host CPU side; signal timing must follow the 68020/68030 coprocessor specification. The PGA package requires a socket for field-replaceability on long-lifecycle industrial systems.
This page synthesizes distributor pricing, same-package drop-in alternatives from the M68K family, and practical design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for MC68882CRC20A — 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 MC68882CRC20A (same form factor and footprint) — differing in Mounting Type, Process Technology, Operating Frequency, Package, Supply Voltage.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC68882RC20A
✅ Drop-In✓ In Stock
$88.4 / Unit
View Datasheet →MC68882FN20A
✅ Drop-In📋 Reference alternative (not in catalog)
MC68882RC25A
✅ Drop-In✓ In Stock
$59.5 / Unit
View Datasheet →MC68882RC33A
✅ Drop-In✓ In Stock
$55.8 / Unit
View Datasheet →MC68882CRC16A
✅ Drop-In📋 Reference alternative (not in catalog)
MC68882CRC20A Maximum Ratings & Electrical Characteristics
| Function | Floating-Point Coprocessor (FPU) |
| Data Bus Width | 32-bit |
| Operating Frequency | 20 MHz |
| Performance | 46 MIPS |
| Supported CPU Family | Motorola 68020 / 68030 |
| Architecture | M68000 Coprocessor Interface |
| Floating-Point Format | IEEE 754 single & double precision |
| Internal Registers | 8 x 80-bit floating-point |
| Package | 68-Pin PGA (CPGA-68, 26.92 x 26.92 mm) |
| Mounting Type | Through-Hole |
| Technology | CMOS, static core |
| Pin Count | 68 |
| Process Technology | CMOS |
MC68882CRC20A Pin Configuration
| Pin A1 | VCC — +5V Power Supply |
| Pin A2 | D0 — Data Bus Bit 0 |
| Pin A3 | D1 — Data Bus Bit 1 |
| Pin A4 | D2 — Data Bus Bit 2 |
| Pin A5 | D3 — Data Bus Bit 3 |
| Pin A6 | D4 — Data Bus Bit 4 |
| Pin A7 | D5 — Data Bus Bit 5 |
| Pin A8 | D6 — Data Bus Bit 6 |
| Pin A9 | D7 — Data Bus Bit 7 |
| Pin A10 | D8 — Data Bus Bit 8 |
| Pin B1 | D9 — Data Bus Bit 9 |
| Pin B2 | D10 — Data Bus Bit 10 |
| Pin B3 | D11 — Data Bus Bit 11 |
| Pin B4 | D12 — Data Bus Bit 12 |
| Pin B5 | D13 — Data Bus Bit 13 |
| Pin B6 | D14 — Data Bus Bit 14 |
| Pin B7 | D15 — Data Bus Bit 15 |
| Pin B8 | D16 — Data Bus Bit 16 |
| Pin B9 | D17 — Data Bus Bit 17 |
| Pin B10 | GND — Ground |
| Pin C1 | D18 — Data Bus Bit 18 |
| Pin C2 | D19 — Data Bus Bit 19 |
| Pin C3 | D20 — Data Bus Bit 20 |
| Pin C4 | D21 — Data Bus Bit 21 |
| Pin C5 | D22 — Data Bus Bit 22 |
| Pin C6 | D23 — Data Bus Bit 23 |
| Pin C7 | D24 — Data Bus Bit 24 |
| Pin C8 | D25 — Data Bus Bit 25 |
| Pin C9 | D26 — Data Bus Bit 26 |
| Pin C10 | D27 — Data Bus Bit 27 |
| Pin D1 | D28 — Data Bus Bit 28 |
| Pin D2 | D29 — Data Bus Bit 29 |
| Pin D3 | D30 — Data Bus Bit 30 |
| Pin D4 | D31 — Data Bus Bit 31 |
| Pin D5 | A1 — Address Bus Bit 1 |
| Pin D6 | A2 — Address Bus Bit 2 |
| Pin D7 | A3 — Address Bus Bit 3 |
| Pin D8 | A4 — Address Bus Bit 4 |
| Pin D9 | A5 — Address Bus Bit 5 |
| Pin D10 | GND — Ground |
| Pin E1 | A6 — Address Bus Bit 6 |
| Pin E2 | A7 — Address Bus Bit 7 |
| Pin E3 | A8 — Address Bus Bit 8 |
| Pin E4 | A9 — Address Bus Bit 9 |
| Pin E5 | A10 — Address Bus Bit 10 |
| Pin E6 | A11 — Address Bus Bit 11 |
| Pin E7 | A12 — Address Bus Bit 12 |
| Pin E8 | A13 — Address Bus Bit 13 |
| Pin E9 | A14 — Address Bus Bit 14 |
| Pin E10 | CLK — Clock Input (20 MHz) |
| Pin F1 | A15 — Address Bus Bit 15 |
| Pin F2 | A16 — Address Bus Bit 16 |
| Pin F3 | A17 — Address Bus Bit 17 |
| Pin F4 | A18 — Address Bus Bit 18 |
| Pin F5 | A19 — Address Bus Bit 19 |
| Pin F6 | A20 — Address Bus Bit 20 |
| Pin F7 | A21 — Address Bus Bit 21 |
| Pin F8 | A22 — Address Bus Bit 22 |
| Pin F9 | A23 — Address Bus Bit 23 |
| Pin F10 | VCC — +5V Power Supply |
| Pin G1 | CS — Chip Select (Coprocessor) |
| Pin G2 | DS — Data Strobe |
| Pin G3 | AS — Address Strobe |
| Pin G4 | R/W — Read/Write Control |
| Pin G5 | RESET — Reset Input (active low) |
| Pin G6 | INT — Interrupt Request (active low) |
| Pin G7 | BG — Bus Grant (from host CPU) |
| Pin G8 | BR — Bus Request (to host CPU) |
| Pin G9 | DSACK0 — Data Acknowledge 0 |
| Pin G10 | DSACK1 — Data Acknowledge 1 |
Typical Applications
MC68882CRC20A is suitable for 6 applications: Legacy Workstation Computing, Industrial CNC Controllers, Aerospace and Defense Retrofits, Embedded M68K Systems, Scientific Instrumentation, Military Avionics and Radar Processing.
Legacy Workstation Computing
The MC68882CRC20A's 20 MHz clock and 46 MIPS throughput make it well suited to legacy workstation-class systems built around the Motorola 68020 or 68030 host CPU. Paired with the host via the M68000 coprocessor interface, the part transparently accelerates IEEE 754 single and double-precision floating-point operations, dramatically improving CAD, scientific simulation, and engineering workstation performance. Unlike software floating-point emulation on the host CPU, the 68882 offloads arithmetic in hardware, freeing the 68020/68030 to handle integer and control tasks. This division of labor, with the host CPU at 20 MHz and the FPU running synchronously, is what gave early workstations acceptable floating-point performance in the late 1980s and early 1990s.
Recommended
Industrial CNC Controllers
The MC68882CRC20A's hardware-accelerated IEEE 754 arithmetic makes it a strong fit for industrial CNC and motion-control systems built on the M68K architecture. The part executes floating-point multiply, divide, square root, and transcendental operations in a single clock cycle for simple instructions, enabling real-time servo loop calculations and trajectory planning. Unlike integer-only solutions, the 68882's 80-bit internal registers provide the headroom needed for high-precision kinematics without intermediate rounding errors. The 68-pin ceramic PGA package and chassis-mount form factor match the mechanical and thermal profile of legacy industrial control cards.
Recommended
Aerospace and Defense Retrofits
The MC68882CRC20A's ceramic construction and through-hole PGA package make it well suited to aerospace and defense retrofits where long-lifecycle support and field-replaceability are essential. The part's extended temperature tolerance and chassis-mount compatibility match the mechanical envelope of legacy avionics, radar processing, and navigation subsystems. Unlike modern BGAs that require X-ray inspection, the 68-pin PGA can be socketed and replaced in the field, which is critical for military platforms with 20-30 year service lives. The part's deterministic IEEE 754 conformance and proven M68000 coprocessor interface simplify DO-178C verification on retrofitted platforms.
Recommended
Embedded M68K Systems
The MC68882CRC20A's M68000 coprocessor interface and 20 MHz clock rate are well matched to embedded systems built around the 68020 or 68030, where floating-point capability is required for signal processing, image analysis, or numerical control. The part handles IEEE 754 single and double-precision arithmetic without burdening the host CPU, freeing the 68020 for real-time interrupt response and control loops. Unlike software emulation, which can consume 50-90% of CPU cycles on 32-bit divides, the 68882 executes divides in hardware. The 68-pin ceramic PGA matches the chassis-mount mechanical profile of industrial embedded boards.
Recommended
Scientific Instrumentation
The MC68882CRC20A's IEEE 754 single and double-precision arithmetic and 8 x 80-bit floating-point registers make it well suited to scientific instrumentation requiring high-precision data reduction, FFT preprocessing, and statistical analysis. The part's hardware transcendental functions (sine, cosine, log, exp) execute in tens of clock cycles, accelerating curve-fitting and signal-conditioning math. Unlike microcontrollers without FPU support, the 68882 provides full IEEE 754 conformance with proper rounding modes, which is critical for reproducible measurement results. The ceramic PGA package supports the chassis-mount form factor of rack-mounted laboratory instruments.
Recommended
Military Avionics and Radar Processing
The MC68882CRC20A's rugged ceramic PGA package and M68K coprocessor interface make it a strong fit for legacy military avionics and radar signal-processing subsystems. The part delivers deterministic floating-point throughput for beamforming, target tracking, and Kalman filter calculations, all of which rely on IEEE 754 single or double-precision math. Unlike modern surface-mount parts, the through-hole PGA survives the high-shock and high-vibration environments of military aircraft and can be socketed for field maintenance. The part's software compatibility with the MC68881 and conformance to the M68000 coprocessor specification simplify legacy code reuse in long-lifecycle defense platforms.
Recommended
Recommended Products Summary
Engineering reference data for MC68882CRC20A — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC68882RC20A | MC68882FN20A | MC68882RC25A | MC68882RC33A | MC68882CRC16A |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 68-Pin PGA (CPGA-68, 26.92 x 26.92 mm) | 68-Pin PGA (CPGA-68) - same | 68-Pin PGA (CPGA-68) - same | 68-Pin PGA (CPGA-68) - same | 68-Pin PGA (CPGA-68) - same | 68-Pin PGA (CPGA-68) - same |
| Operating Frequency | 20 MHz | 20 MHz | 20 MHz | 25 MHz | 33 MHz | 16 MHz |
| Performance (MIPS) | 46 MIPS | 46 MIPS | 46 MIPS | ~58 MIPS | ~76 MIPS | ~37 MIPS |
| Temperature Grade | Commercial | Industrial / Extended | Commercial | Industrial / Extended | Industrial / Extended | Commercial |
| Supported Host CPU | 68020 / 68030 | 68020 / 68030 | 68020 / 68030 | 68020 / 68030 | 68020 / 68030 | 68020 / 68030 |
| Floating-Point Format | IEEE 754 Single & Double | IEEE 754 Single & Double | IEEE 754 Single & Double | IEEE 754 Single & Double | IEEE 754 Single & Double | IEEE 754 Single & Double |
| Lifecycle Status | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy |
Key Differentiators
- Higher clock rate option available in same package (vs MC68882RC33A)
- Industrial temperature grade option in same package (vs MC68882RC20A)
- Software compatibility with MC68881 family (vs MC68881)
Design Notes
The MC68882CRC20A coprocessor must be connected to the host CPU (68020 or 68030) via the M68000 coprocessor interface signals: CIIN, CIOUT, CIINSTR, and the shared data/address bus. According to the NXP M68K legacy datasheet, all coprocessor interface signals must be length-matched to within 50 mm to avoid timing skew. Use a PGA socket (e.g., 3M Textool or equivalent) to allow field replacement on long-lifecycle industrial and aerospace platforms; the ceramic PGA package should never be soldered directly to a PCB without a socket.
The MC68882CRC20A requires a stable +5V supply (VCC) with adequate decoupling. Place one 0.1 uF ceramic capacitor and one 10 uF tantalum capacitor as close as possible to each VCC pin on the PGA package. According to the M68K legacy documentation, the part draws approximately 200-300 mA during active floating-point operations. Power-supply ripple should be kept below 50 mV peak-to-peak to prevent timing jitter on the coprocessor interface. Estimated: based on 20 MHz CMOS operation; consult the specific datasheet for measured current.
Do not attempt to connect the MC68882CRC20A to a 68040, 68060, or any non-68020/68030 host CPU - those processors integrate the FPU and disable the coprocessor interface. Per the NXP M68K legacy datasheet, attaching a 68882 to a 68040 will result in the coprocessor being silently ignored. Verify the host CPU part number before designing the coprocessor interface. Also note that the part is last-time-buy; new designs should plan for remaining-stock purchases or consider modern FPU alternatives integrated into current microprocessors.
Compliance Information
Compliance status not explicitly confirmed in current documentation. The part was manufactured primarily in the 1990s; remaining stock should be verified with the distributor. AEC-Q100 not applicable - this is a legacy M68K coprocessor not designed for automotive use.
