×

Programmable impedance output driver

  • US 5,666,078 A
  • Filed: 02/07/1996
  • Issued: 09/09/1997
  • Est. Priority Date: 02/07/1996
  • Status: Expired due to Fees
First Claim
Patent Images

1. An output driver circuit, comprising:

  • an external resistance device for programming a desired impedance into said output driver circuit;

    a voltage comparative device, coupled to said extreme resistance device, for comparing a voltage of said desired impedance with an evaluate voltage and generating a signal indicating which of said voltages is higher;

    a control logic device, coupled to said voltage comparative device, for receiving said signal and generating a first and second count from said signal, wherein said second count corresponds to a prior first count;

    an evaluate device, coupled to said control logic device and said voltage comparative device, for receiving said first count and modifying said evaluate voltage with said first count to more closely resemble said voltage of said desired impedance;

    a low select device, coupled to said control logic device, for receiving said first and second count, and selecting and outputting the lowest of said first and second count; and

    an output device, coupled to said low select device, for receiving said output of said low select device and generating an output impedance corresponding to said output of said low select device.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×