DEC part number

DEC part numbers are generally of the form 'ww-xxxxx-yy zzzz' (sometimes the first hyphen is omitted). DEC had a system for their part numbers, such that looking at a part number will generally tell you (based on the leading two-digit field, the 'class code') what kind of part it is: chip, cable, etc. The next field is a 'basic identifier', then comes a 'variation identifier'; the final, optional, field is the 'revision identifier'.

It should be noted that DEC had several other namespaces for things produced by the company (such as DEC engineering drawing numbers; and the identification numbers of FLIP CHIPs and later component PCBs, of the form 'Xyyyy', where 'X' is a capital letter, and 'yyyy' are digits), but these numbers are not 'DEC part numbers', as defined by the applicable DEC specifications (below).

This table lists the major class codes:

Class	Type
10	Capacitors
11	Diodes
12	Mechanical and electro-mechanical items (connectors, pins, bearings, belts, fans, etc)
13	Resistors
15	Transistors
16	Transformers and inductors
17	Wire and fiber optic cables
18	Crystals and other oscillators
19	Bipolar integrated circuits
21	MOS chips (CPUs, etc)
23	Fixed memory chips (ROMs, etc)
24	Fiber-optic components
30	Core memory stacks, major components
36	Paper tape, punched cards, labels
50	Printed circuit boards
52	Pulse transformers
54	Assemblies (circuit cards, display panels, etc)
70	Cables/harnesses/backplanes
74	'Manufactured non-electrical parts' (includes decals, etc)
90	Fastener hardware (nuts, bolts, screws, washers, ties etc)
91	Hook up wire and tubing

External links

• DEC STD 012-0 Part Identification Standard
• DEC STD 012-2 Unified Numbering Code for Part Identifier Class Codes
• How to identify computer chips or integrated circuits on circuit boards