The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 25, 1996
Filed:
Jan. 13, 1994
John D Hamre, Plymouth, MN (US);
Denton G Wicklund, Delano, MN (US);
Steven D Barkley, Roseville, MN (US);
Network Systems Corporation, Minneapolis, MN (US);
Abstract
A circuit board capable of live-insertion or hot-swapping into a live chassis backplane. The circuit board is provided with a power control circuitry for gracefully ramping up board power after insertion, or gracefully removing power just prior to physical removal of a circuit board from the board slot. A pair of ejector levers are provided on each side of the circuit board. A push button switch is provided proximate one ear thereof and is selectively opened or closed depending upon the position of an ejector cover which can be secured thereover in an interlocking relationship. Upon retraction of the extractor cover, the switch is opened, and the converse applies. Power MOSFETs are provided between the card edge and the board power busses which are gracefully turned on and off as a function of the switch position. A high-side gate driver provides an increased bias voltage, which bias voltage is communicated through the closed switch to the gates of the MOSFETs. An RC network is coupled to the MOSFET gate to determine the time constant at which bias voltage will be ramped up or ramped down to correspondingly ramp power up or down to the circuit board power busses. A power supply monitor circuit is also provided for automatically resetting the board upon a power up condition.