Motorola MC68882FN16AR2

The MC68882 operates with an MC68020 or MC68030 as a coprocessor and can be interfaced as a peripheral processor in other M68000-family systems. It provides eight general-purpose 80-bit floating-point registers, a 67-bit arithmetic unit, status and control registers, and support for concurrent instruction processing. Verify board-level bus timing and exact device markings when servicing a legacy system.

• IEEE 754-1985 binary floating-point support for M68000-family systems.
• Eight 80-bit floating-point data registers and a 67-bit arithmetic path.
• Single, double and extended precision real formats, plus integer and packed-decimal types.
• Concurrent coprocessor and host execution where the bus interface permits.
• Software and pin compatibility within the documented MC68881/MC68882 interface, subject to system checks.

The original technical summary identifies 46 floating-point instructions, a 67-bit barrel shifter, conversion hardware, eight FP0-FP7 registers, and FPCR, FPSR and FPIAR control/status registers. Arithmetic, transcendental, data-movement and exception operations integrate through the M68000 coprocessor protocol. The host processor handles effective addresses and requested data transfers.

The FN16A manufacturer package declaration specifies PLCC 68. The exact FN16AR2 distributor entry identifies a 68-terminal plastic J-lead chip carrier; R2 packing details require lot verification. The local register uses 68-LCC (J-Lead) and expects the image below. Confirm seating height, pin-one alignment and socket fit with the controlled PLCC drawing.

Assembly checks

• Verify all 68 J-leads and chip-carrier orientation.
• Inspect socket contact condition and device marking.
• Check board thermal and supply decoupling design.

The registered local 68-LCC JPG is missing.

The Motorola technical summary groups A0-A4 as bus address inputs and D0-D31 as the bidirectional data bus. SIZE, AS, CS, R/W and DS qualify bus cycles; DSACK0/DSACK1 acknowledge transfer size. RESET, CLK, SENSE, VCC and GND provide system control and power connections. One position is reserved as NC. Use the manufacturer PLCC pin-out drawing for numbered terminals; do not substitute the PGA diagram.

Absolute maximum ratings and timing conditions must be checked in the controlled Motorola/Freescale summary before board-level use.

No LCDChip alternative is approved or linked. MC68882FN16A is another exact-family order code but package, packing and lot identity still require confirmation. MC68881 is software/pin compatible in the family documentation but has different performance; higher-speed MC68882 grades must also be evaluated against clock and bus timing. Never assume interchangeability from the base number alone.

The Motorola/Freescale BR509 technical summary, now hosted by NXP, documents the MC68882 architecture, interface, signal groups and 16.67 MHz electrical column. NXP's manufacturer package declaration identifies the FN16A base configuration as PLCC 68. The exact FN16AR2 suffix is separately identified in a Rochester distributor listing; confirm its reel and lot records before assembly.

• Legacy MC68020 and MC68030 systems requiring hardware floating point.
• Scientific and instrumentation controllers based on M68000-family buses.
• Repair of boards designed for a 68-lead MC68882 PLCC device.

Check Motorola or successor markings, the full FN16AR2 suffix, date/lot code, lead finish, package geometry and original packing. This is a legacy part; confirm provenance, ESD handling and moisture history. Public distributor availability and tier prices vary by channel and date and should be reconciled through an authorized quote before catalog updates.

Verify the exact lot, FN16AR2 packing suffix, PLCC orientation, 5 V supply and 16.67 MHz grade timing against the board design. Missing package artwork and unreconciled current stock/price terms block publication.