Hot-swap capability
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Model 6276 User Guide
3 • System architecture
the change in load. The power supply, ground and signal pins on the connectors are staged to allow sequenc-
ing, so as to not disturb the operation of the surrounding boards in the bus. The three levels of sequencing are:
•
Short pins for BD_SEL#
•
Medium pins for signals
•
Long pins for power/ground
The system uses two levels of sequencing so that power/ground is made first/broken last. The short pin
(BD_SEL#) connection is made only when the board is firmly seated, which signals the control circuitry to
power up any high-current devices. Conversely, BD_SEL# breaks first to provide early warning to the
control circuitry.
