US 5,293,636 A · Module for insertion into a multi-module system having electronic keying for preventing power to improperly connected modules with improperly configured diode connections

Abstract

A computer system with a number of subsystems or modules on separate circuit boards employs electronic keying to ensure proper configuration of these boards. A power key arrangement associated with a plug-in connector enables a separate power supply for each set of boards. A power supply turn-on signal is routed through a uniquely-configured connector path for each board, so the power supply turn-on is inhibited for improper configurations. The uniquely-configured connector path may use either a series or a parallel implementation. The series implementation employs a set of diodes connected for conduction in either of two directions, with the mating connector having its conductor paths connected to match the diode configuration; in this manner, the power supply enable signal can only flow through the series path if the proper board is plugged into a properly-coded slot, in which case the power supply to activate this board is activated through the series path including the diodes. The parallel implementation employs a given number of connector pins to establish the coding for each board, and each pin is either open-circuited or connected to ground; if this coding of the subsystem board is not the same as that of the slot into which it is plugged then the power supply activation signal will be shorted to ground by one or the other of the coded pins.

Claims3

Dependent claims

A module adapted to be inserted into a computer system having a system board, and a power supply, said system board having a plurality of first connector elements electrically interconnected in a first key configuration, said module comprising:

a plug-in assembly adapted for connection to the system board;
and
an electrical keying circuit to enable operation of said module only when properly configured by said plug-in assembly in said system board, said keying circuit comprising:
a plurality of second connector elements located upon said module and adapted to engage the first connector elements located upon the system board;
a plurality of directional electrical connections configured on said module and separately engaging said plurality of connector elements to define a second key configuration, each of said directional electrical connections conducting only in one direction;
and
electrical power supply means for supplying enabling voltage from said power supply to said module only when said first and second key configurations enable a series connection through said plurality of directional electrical connections for conduction in a single direction.

4 more elements

Dependencies are inferred from the claim text.

Module for insertion into a multi-module system having electronic keying for preventing power to improperly connected modules with improperly configured diode connections

Life of this patent

Module for insertion into a multi-module system having electronic keying for preventing power to improperly connected modules with improperly configured diode connections

Life of this patent

Abstract

Claims3