M651

This document is a schematic diagram for a Digital Equipment Corporation (DEC) M651 Negative Output Converter.

Key information includes:

• Purpose: It describes the circuitry for a negative output converter, designated M651.
• Proprietary Nature: The schematic is proprietary to DEC, intended for test and maintenance purposes, and copyrighted 1969 by Digital Equipment Corporation.

• Components: The circuit extensively uses a variety of discrete components including:

  • Integrated Circuits (DEC 7410N).
  • Transistors (DEC 3009B-S and DEC 6534B, equivalent to 2N3009 and MPS6534 respectively).
  • Resistors of various values (e.g., 1.5K, 1K, 470, 3K, 82 ohms).
  • Diodes (IN750A, D662/IN645, D664/IN3606).
  • Capacitors (0.01 MFD and 330 MMF).

• Power Rails/Signals: The schematic shows connections to +5V (A), Ground (C), +1.2V, and -15V (B), indicating its role in power conversion or regulation.

• Date: The drawing date is February 3, 1969.