IC number:	80387DX
IC function:	Floating-point co-processor
Related components:	8087, 80287 (predecessors), 80387SX (limited version), 80486DX, 80486DX2 (successors), 80386DX (main processor)

Component documentation

IC number	Manufacturer	Documentation
i387DX (80387DX)	Intel	Datasheet (PDF)

Component versions

IC number	Package
A80387DX	68-pin Ceramic PGA 11 × 11

Positions

Device	Position	Package
PC60-III	U83 (not installed)	PGA

Pinout

Pin	Type	Name
A2	I/O	D9
A3..A4	I/O	D11..D12
A5	I/O	D14
A6	Power	VCC
A7	I/O	D16
A8	I/O	D18
A9	Power	VCC
A10	I/O	D21
B1	I/O	D8
B2	Power	VSS
B3	I/O	D10
B4	Power	VCC
B5	I/O	D13
B6	I/O	D15
B7	Power	VSS
B8	I/O	D17
B9..B10	I/O	D19..D20
B11	I/O	D22
C1..C2	I/O	D7..D6
C10	I/O	D23
C11	Power	VSS
D1..D2	I/O	D5..D4
D10..D11	I/O	D24..D25
E1	Power	VCC
E2	Power	VSS
E10..E11	I/O	D26..D27
F1	Power	VCC
F2	Input	VSS
F10	Power	VCC
F11	Power	VSS
G1..G2	I/O	D3..D2
G10..G11	Input	D28..D29
H1..H2	Input	D1..D0
H10..H11	I/O	D30..D31
J1	Power	VSS
J2	Power	VCC
J10	Power	VSS
J11	Input	CKM
K1	Output	PEREQ
K2	Output	BUSY#
K3	Input	TIE HIGH
K4	Input	W/R#
K5	Power	VCC
K6	Input	NPS2
K7	Input	ADS#
K8	Input	READY#
K9	N/C	N/C
K10	Input	CPUCLK2
K11	Input	NUMCLK2
L2	Output	ERROR#
L3	Output	READYO#
L4	Input	STEN
L5	Power	VSS
L6	Input	NPS1#
L7	Power	VCC
L8	Input	CMD0#
L9	Input	TIE HIGH
L10	Input	RESETIN