Prefix 		Manufacturer
-----------------	--------------------------------------------
AD 		Analog Devices
Am 		Advanced Microdevices
CA, CD 	RCA (now part of Harris)
DM 		National Semiconductor
H 		Harris
HA 		Hitachi
I 		Intel
ICL, ICM 	Intersil
IDT 		Integrated Device Technology
L, LD 		Siliconix
LF, LH, LM 	National Semiconductor
LT 		Linear Technology
MC, MM 	Motorola
N, NE 		Signetics
PM 		Precision Monolithics
SE 		Signetics
SN 		Texas Instruments
SP 		Plessey
TL 		Texas Instruments
WD 		Western Digital
XR 		Exar
mA 		Fairchild Semiconductor  (now part of National Semiconductor)