Electrical computers and digital data processing systems: input/ – Intrasystem connection – Bus expansion or extension
Reexamination Certificate
2005-11-01
2005-11-01
Myers, Paul R. (Department: 2111)
Electrical computers and digital data processing systems: input/
Intrasystem connection
Bus expansion or extension
C710S301000, C326S070000
Reexamination Certificate
active
06961795
ABSTRACT:
An apparatus and method for indicating and allowing hot swapping of a circuit board. During both insertion and extraction of a circuit board from a system, two inputs signals are generated from staggered pins located on the circuit board's connector. The inputs are processed through a NAND function implemented with transistors and output to two Schmitt trigger inverters connected in series. The output of the series connection of Schmitt trigger inverters goes high when both input signals are high and goes low when one of the inputs signals goes low. In addition, through the use of a resistor, capacitor combination connected to the input of the first Schmitt trigger inverter, the output signal remains high for a period of time after one of the input signals goes low. This additional period of time prevents any damage or disruption of signaling caused by transient current and voltage fluctuations as a circuit board is inserted or extracted. The output signal can be used in both single-ended and differential SCSI applications.
REFERENCES:
patent: 4245270 (1981-01-01), Busby
patent: 4886984 (1989-12-01), Nakaoka
patent: 5202965 (1993-04-01), Ahn et al.
patent: 5317697 (1994-05-01), Husak et al.
patent: 5586271 (1996-12-01), Parrett
patent: 5604873 (1997-02-01), Fite et al.
patent: 5758102 (1998-05-01), Carey et al.
patent: 5910690 (1999-06-01), Dorsey et al.
patent: 6487624 (2002-11-01), Erickson et al.
patent: 6625681 (2003-09-01), Erickson et al.
Brush Richard K.
Erickson Michael John
Myers Paul R.
Phan Raymond N
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