Browse Prior Art Database

A SOLUTION TO PRECHARGING BUS CAPACITANCE IN A HOT PLUG ENVIRONMENT

IP.com Disclosure Number: IPCOM000014229D
Original Publication Date: 2000-Oct-01
Included in the Prior Art Database: 2003-Jun-19
Document File: 3 page(s) / 49K

Publishing Venue

IBM

Abstract

Disclosed is a method for removal of the voltage dip on the system voltage bus due to the addition of power bus bulk capacitance to said bus. If the bulk capacitance is added directly to the system voltage bus, the effective short circuit of the added capacitance can cause the system bus voltage to drop out of tolerance.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 3

  A SOLUTION TO PRECHARGING BUS CAPACITANCE IN A HOT PLUG ENVIRONMENT

  Disclosed is a method for removal of the voltage dip on the system voltage bus due to the addition of power bus bulk capacitance to said bus. If the bulk capacitance is added directly to the system voltage bus, the effective short circuit of the added capacitance can cause the system bus voltage to drop out of tolerance.

This method is comprised of a two-stage connection system. Figure 1 shows a two-contact blade with contact separation by a gap d. Resistance R is between Contact 1 and Contact 2. As the system voltage bus touches Contact 1, current limited by resistor contact wipe longer than d, and a mechanical delay of time tm. R flows to charge the power bus capacitance. This time is noted by tc1. Gap d may provide enough delay if the capacitance is small; otherwise, a mechanical stop will be incorporated to provide additional time delay (tm) to fully charge the power bus capacitance. During the delay of time t total, the resistor limits the current to a value that will charge the capacitance keeping the bus voltage within its allowable tolerance. Once the delay has been achieved, the printed circuit board tab is inserted the rest of the way into the connector shorting out the resistor, connecting the capacitance directly to the system voltage bus.

1

Page 2 of 3

(hardcopy figure here)

2

Page 3 of 3

(hardcopy figure here)

3