W519

This document is a schematic diagram titled "POWER SEQUENCE AND CROBAR" (Number W519-0-1, Revision D) from Digital Equipment Corporation, copyrighted 19ST.

Key aspects of the document include:

• Circuit Diagram: It illustrates an electronic circuit designed for power sequencing and a "crowbar" protection function. The circuit features multiple transistors (Q1-Q8), diodes (D1-D13, D664, D662), resistors, capacitors, and integrated circuits (E1=DEC9601, E2=DEC7401). It includes inputs/outputs for "POWER ENABLE," "CROBAR RELEASED," "CROBAR RELEASE DELAY," and "CROBAR CONTACT."
• Component Specifications: A section titled "UNLESS OTHERWISE INDICATED" provides default specifications for diodes (D662), resistors (1/4W, 5%), capacitors (.01uF, 100V, 20%), transistors (DEC30098), and ICs (DEC9601, DEC7401), along with pin assignments.
• Parts List: A comprehensive table enumerates all required components, including handles, eyelets, ICs, transistors, various resistors, a relay, diodes, capacitors, an etched circuit card, and module/assembly details, with their DEC part numbers, descriptions, and quantities.
• Conversion Chart: A "TRANSISTOR & DIODE CONVERSION CHART" maps DEC part numbers (DEC30098, D662, D664) to standard EIA equivalents (2N3009, IN3608, IN645).
• Additional Diagram: A smaller diagram (bottom center) appears to show component interconnections or a layout for part of the circuit.
• Proprietary Notice: The document explicitly states that the schematic is for test and maintenance purposes only, the circuits are proprietary, and should be treated accordingly.