Patent · US Expired

Circuit for controlling current in an adapter card

US5572395A · kind A · utility

45Cited by
14References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 21, 1993
Grant dateNov 5, 1996
Priority date
Expiry dateDec 21, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H9/004
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A circuit embodied within an adapter card for hot-plugging with a card slot in a card slot coupled to a processor based system utilizes a biasing circuit for ensuring that the input voltage to the load of the adapter card is of a sufficient magnitude. The circuit also includes a FET/feedback circuit for opening and closing the circuit provided between the input voltage to the adapter card and the load. This FET/feedback circuit operates as a constant current source to charge the input capacitance of the load and converts to a switched mode when the load capacitance is fully charged. The biasing circuit controls the FET/feedback circuit so that it remains open during hot-plugging of the adapter card into the card slot to alleviate pin arching. A monitor/timer circuit prevents the FET/feedback circuit from operating in the constant-current mode for no longer than a predetermined amount of time. A latch circuit is provided to turn off the FET within the FET/feedback circuit upon sensing of a transient current through the load.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.