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

Component documentation

IC number	Manufacturer	Documentation
i387SX (80387SX)	Intel	Datasheet (PDF)

Component versions

IC number	Package
N80387SX	68-pin PLCC

Positions

Device	Position	Package
A2386	U102 (not installed)	PLCC
SL386SX CPU card w/cache DB1	U102 (not installed)	PLCC
SL286/SL386SX CPU card DB2	U102 (not installed)	PLCC

Pinout

Pin	Type	Name	Signal name
			SL386SX CPU card DB1	SL386SX CPU card DB2
1	N/C	NC	unused
2..3	I/O	D07..D06	CD7..CD6	D7..D6
4	Power	VCC	VCC
5	Power	VSS	GND
6..8	I/O	D05..D03	CD5..CD3	D5..D3
9	Power	VCC	VCC
10	N/C	NC	unused
11..12	I/O	D15..D14	CD15..CD14	D15..D14
13	Power	VCC	VCC
14	Power	VSS	GND
15..16	I/O	D13..D12	CD13..CD12	D13..D12
17..18	N/C	NC	unused
19..20	I/O	D00..D01	CD0..CD1	D0..D1
21	Power	VCC	VCC
22	Power	VSS	GND
23	I/O	D02	CD2	D2
24	I/O	D08	CD8	D8
25	Power	VSS	GND
26	Power	VCC	VCC
27	Power	VSS	GND
28..30	I/O	D09..D11	CD9..CD11	D9..D11
31	Power	VCC	VCC
32	Power	VSS	GND
33	Power	VCC	VCC
34	Power	VSS	GND
35	Output	ERROR#	NERRORNPX
36	Output	BUSY#	NBUSYNPX
37	Power	VCC	VCC
38	Power	VSS	GND
39	Power	VCC	VCC
40	Input	STEN	STEN_PU
41	Input	W/R#	386CB6	W_NR_NS0
42	Power	VSS	GND
43	Power	VCC	VCC
44	Input	NPS1#	386CB4	M_NIO
45	Input	NPS2	CA23	A23
46	Power	VCC	VCC
47	Input	ADS#	386CB3	NADS
48	Input	CMD0#	CA2	A2
49	Input	READY#	NCRDY	NRDY0320
50	Power	VCC	VCC
51	Input	RESETIN	RESNPX
52	N/C	NC	unused
53	Input	NUMCLK2	NUMCLK2_PU
54	Input	CPUCLK2	CLK2	386CLK
55	Power	VSS	GND
56	Output	PEREQ	PEREQNPX
57	Output	READYO#	NRDYNPX_PU
58	Power	VCC	VCC
59	Input	CKM	CKM_PU_JP
60..61	Power	VSS	GND
62	Power	VCC	VCC
63	Power	VSS	GND
64	Power	VCC	VCC
65	N/C	NC	unused
66	Power	VSS	GND
67..68	N/C	NC	unused