MC68882CRC20A - 32-bit Floating-Point Coprocessor, 20 MHz | NXP
MPN: MC68882CRC20A ⚠ Lần mua cuốiMC68882CRC20A Tóm tắt
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.
Bộ thay thế dễ dàng lắp đặt cho MC68882CRC20A — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với MC68882CRC20A (cùng hình factor và footprint) — khác nhau ở Mounting Type, Process Technology, Operating Frequency, Package, Supply Voltage.
MC68882RC20A
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC68882FN20A
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC68882RC25A
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC68882RC33A
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC68882CRC16A
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC68882CRC20A Tỷ lệ tối đa & tính chất điện
| Chức năng | Floating-Point Coprocessor (FPU) |
| Bề rộng đường dữ liệu | 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 |
| Hộp | 68-Pin PGA (CPGA-68, 26.92 x 26.92 mm) |
| Kiểu lắp đặt | Through-Hole |
| Technology | CMOS, static core |
| Số chân | 68 |
| Process Technology | CMOS |
Cấu hình chân MC68882CRC20A
| Chân A1 | VCC — +5V Power Supply |
| Chân A2 | D0 — Data Bus Bit 0 |
| Chân A3 | D1 — Data Bus Bit 1 |
| Chân A4 | D2 — Data Bus Bit 2 |
| Chân A5 | D3 — Data Bus Bit 3 |
| Chân A6 | D4 — Data Bus Bit 4 |
| Chân A7 | D5 — Data Bus Bit 5 |
| Chân A8 | D6 — Data Bus Bit 6 |
| Chân A9 | D7 — Data Bus Bit 7 |
| Chân A10 | D8 — Data Bus Bit 8 |
| Chân B1 | D9 — Data Bus Bit 9 |
| Chân B2 | D10 — Data Bus Bit 10 |
| Chân B3 | D11 — Data Bus Bit 11 |
| Chân B4 | D12 — Data Bus Bit 12 |
| Chân B5 | D13 — Data Bus Bit 13 |
| Chân B6 | D14 — Data Bus Bit 14 |
| Chân B7 | D15 — Data Bus Bit 15 |
| Chân B8 | D16 — Data Bus Bit 16 |
| Chân B9 | D17 — Data Bus Bit 17 |
| Chân B10 | GND — Ground |
| Chân C1 | D18 — Data Bus Bit 18 |
| Chân C2 | D19 — Data Bus Bit 19 |
| Chân C3 | D20 — Data Bus Bit 20 |
| Chân C4 | D21 — Data Bus Bit 21 |
| Chân C5 | D22 — Data Bus Bit 22 |
| Chân C6 | D23 — Data Bus Bit 23 |
| Chân C7 | D24 — Data Bus Bit 24 |
| Chân C8 | D25 — Data Bus Bit 25 |
| Chân C9 | D26 — Data Bus Bit 26 |
| Chân C10 | D27 — Data Bus Bit 27 |
| Chân D1 | D28 — Data Bus Bit 28 |
| Chân D2 | D29 — Data Bus Bit 29 |
| Chân D3 | D30 — Data Bus Bit 30 |
| Chân D4 | D31 — Data Bus Bit 31 |
| Chân D5 | A1 — Address Bus Bit 1 |
| Chân D6 | A2 — Address Bus Bit 2 |
| Chân D7 | A3 — Address Bus Bit 3 |
| Chân D8 | A4 — Address Bus Bit 4 |
| Chân D9 | A5 — Address Bus Bit 5 |
| Chân D10 | GND — Ground |
| Chân E1 | A6 — Address Bus Bit 6 |
| Chân E2 | A7 — Address Bus Bit 7 |
| Chân E3 | A8 — Address Bus Bit 8 |
| Chân E4 | A9 — Address Bus Bit 9 |
| Chân E5 | A10 — Address Bus Bit 10 |
| Chân E6 | A11 — Address Bus Bit 11 |
| Chân E7 | A12 — Address Bus Bit 12 |
| Chân E8 | A13 — Address Bus Bit 13 |
| Chân E9 | A14 — Address Bus Bit 14 |
| Chân E10 | CLK — Clock Input (20 MHz) |
| Chân F1 | A15 — Address Bus Bit 15 |
| Chân F2 | A16 — Address Bus Bit 16 |
| Chân F3 | A17 — Address Bus Bit 17 |
| Chân F4 | A18 — Address Bus Bit 18 |
| Chân F5 | A19 — Address Bus Bit 19 |
| Chân F6 | A20 — Address Bus Bit 20 |
| Chân F7 | A21 — Address Bus Bit 21 |
| Chân F8 | A22 — Address Bus Bit 22 |
| Chân F9 | A23 — Address Bus Bit 23 |
| Chân F10 | VCC — +5V Power Supply |
| Chân G1 | CS — Chip Select (Coprocessor) |
| Chân G2 | DS — Data Strobe |
| Chân G3 | AS — Address Strobe |
| Chân G4 | R/W — Read/Write Control |
| Chân G5 | RESET — Reset Input (active low) |
| Chân G6 | INT — Interrupt Request (active low) |
| Chân G7 | BG — Bus Grant (from host CPU) |
| Chân G8 | BR — Bus Request (to host CPU) |
| Chân G9 | DSACK0 — Data Acknowledge 0 |
| Chân G10 | DSACK1 — Data Acknowledge 1 |
Ứng dụng tiêu biểu
MC68882CRC20A phù hợp cho 6 Áp dụngs: 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.
Được đề xuất
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.
Được đề xuất
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.
Được đề xuất
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.
Được đề xuất
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.
Được đề xuất
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.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MC68882CRC20A — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | 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 |
Bảo phân biệt quan trọng
- Higher clock rate option available in same package (vsMC68882RC33A)
- Industrial temperature grade option in same package (vsMC68882RC20A)
- Software compatibility with MC68881 family (vsMC68881)
Ghi chú thiết kế
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.
Thông tin tuân thủ
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.
