MC68882CRC20A - 32-bit Floating-Point Coprocessor, 20 MHz | NXP
MPN: MC68882CRC20A ⚠ آخرین فرصت خریدMC68882CRC20A نمای کلی
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.
جایگزین‌های drop-in برای MC68882CRC20A — همان پکیج، سازگار پین‌به‌پین. قطعات با پکیج متفاوت که نیاز به تغییر PCB دارند مستثنی هستند.
گونه‌ها در این سری
مدل‌های هم‌سری که جایگزین مستقیم هستند برای MC68882CRC20A (همان فرم‌فاکتور و فوت‌پرینت) — متفاوت در Mounting Type, Process Technology, Operating Frequency, Package, Supply Voltage.
MC68882RC20A
✅ جایگزین مستقیمبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←MC68882FN20A
✅ جایگزین مستقیم📋 جایگزین مرجع (خارج از کاتالوگ)
MC68882RC25A
✅ جایگزین مستقیمبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←MC68882RC33A
✅ جایگزین مستقیمبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←MC68882CRC16A
✅ جایگزین مستقیم📋 جایگزین مرجع (خارج از کاتالوگ)
MC68882CRC20A حداکثر مقادیر مجاز و مشخصات الکتریکی
| عملکرد | Floating-Point Coprocessor (FPU) |
| عرض گذرگاه داده | 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 |
| بسته‌بندی | 68-Pin PGA (CPGA-68, 26.92 x 26.92 mm) |
| نوع نصب | Through-Hole |
| Technology | CMOS, static core |
| تعداد پایه | 68 |
| Process Technology | CMOS |
پیکربندی پین MC68882CRC20A
| پین A1 | VCC — +5V Power Supply |
| پین A2 | D0 — Data Bus Bit 0 |
| پین A3 | D1 — Data Bus Bit 1 |
| پین A4 | D2 — Data Bus Bit 2 |
| پین A5 | D3 — Data Bus Bit 3 |
| پین A6 | D4 — Data Bus Bit 4 |
| پین A7 | D5 — Data Bus Bit 5 |
| پین A8 | D6 — Data Bus Bit 6 |
| پین A9 | D7 — Data Bus Bit 7 |
| پین A10 | D8 — Data Bus Bit 8 |
| پین B1 | D9 — Data Bus Bit 9 |
| پین B2 | D10 — Data Bus Bit 10 |
| پین B3 | D11 — Data Bus Bit 11 |
| پین B4 | D12 — Data Bus Bit 12 |
| پین B5 | D13 — Data Bus Bit 13 |
| پین B6 | D14 — Data Bus Bit 14 |
| پین B7 | D15 — Data Bus Bit 15 |
| پین B8 | D16 — Data Bus Bit 16 |
| پین B9 | D17 — Data Bus Bit 17 |
| پین B10 | GND — Ground |
| پین C1 | D18 — Data Bus Bit 18 |
| پین C2 | D19 — Data Bus Bit 19 |
| پین C3 | D20 — Data Bus Bit 20 |
| پین C4 | D21 — Data Bus Bit 21 |
| پین C5 | D22 — Data Bus Bit 22 |
| پین C6 | D23 — Data Bus Bit 23 |
| پین C7 | D24 — Data Bus Bit 24 |
| پین C8 | D25 — Data Bus Bit 25 |
| پین C9 | D26 — Data Bus Bit 26 |
| پین C10 | D27 — Data Bus Bit 27 |
| پین D1 | D28 — Data Bus Bit 28 |
| پین D2 | D29 — Data Bus Bit 29 |
| پین D3 | D30 — Data Bus Bit 30 |
| پین D4 | D31 — Data Bus Bit 31 |
| پین D5 | A1 — Address Bus Bit 1 |
| پین D6 | A2 — Address Bus Bit 2 |
| پین D7 | A3 — Address Bus Bit 3 |
| پین D8 | A4 — Address Bus Bit 4 |
| پین D9 | A5 — Address Bus Bit 5 |
| پین D10 | GND — Ground |
| پین E1 | A6 — Address Bus Bit 6 |
| پین E2 | A7 — Address Bus Bit 7 |
| پین E3 | A8 — Address Bus Bit 8 |
| پین E4 | A9 — Address Bus Bit 9 |
| پین E5 | A10 — Address Bus Bit 10 |
| پین E6 | A11 — Address Bus Bit 11 |
| پین E7 | A12 — Address Bus Bit 12 |
| پین E8 | A13 — Address Bus Bit 13 |
| پین E9 | A14 — Address Bus Bit 14 |
| پین E10 | CLK — Clock Input (20 MHz) |
| پین F1 | A15 — Address Bus Bit 15 |
| پین F2 | A16 — Address Bus Bit 16 |
| پین F3 | A17 — Address Bus Bit 17 |
| پین F4 | A18 — Address Bus Bit 18 |
| پین F5 | A19 — Address Bus Bit 19 |
| پین F6 | A20 — Address Bus Bit 20 |
| پین F7 | A21 — Address Bus Bit 21 |
| پین F8 | A22 — Address Bus Bit 22 |
| پین F9 | A23 — Address Bus Bit 23 |
| پین F10 | VCC — +5V Power Supply |
| پین G1 | CS — Chip Select (Coprocessor) |
| پین G2 | DS — Data Strobe |
| پین G3 | AS — Address Strobe |
| پین G4 | R/W — Read/Write Control |
| پین G5 | RESET — Reset Input (active low) |
| پین G6 | INT — Interrupt Request (active low) |
| پین G7 | BG — Bus Grant (from host CPU) |
| پین G8 | BR — Bus Request (to host CPU) |
| پین G9 | DSACK0 — Data Acknowledge 0 |
| پین G10 | DSACK1 — Data Acknowledge 1 |
کاربردهای معمول
MC68882CRC20A مناسب است برای 6 کاربردs: 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.
پیشنهادی
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.
پیشنهادی
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.
پیشنهادی
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.
پیشنهادی
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.
پیشنهادی
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.
پیشنهادی
خلاصه محصولات پیشنهادی
داده‌های مرجع مهندسی برای MC68882CRC20A — مقایسه، راهنمای طراحی و اطلاعات انطباق.
راهنمای انتخاب
مقایسه با جایگزین‌ها
| پارامتر | این محصول | 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 |
تفاوت‌های کلیدی
- Higher clock rate option available in same package (در مقابلMC68882RC33A)
- Industrial temperature grade option in same package (در مقابلMC68882RC20A)
- Software compatibility with MC68881 family (در مقابلMC68881)
یادداشت‌های طراحی
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.
اطلاعات انطباق
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.
