×

Dual integration circuit

  • US 5,200,623 A
  • Filed: 12/04/1991
  • Issued: 04/06/1993
  • Est. Priority Date: 12/04/1991
  • Status: Expired due to Term
First Claim
Patent Images

1. A method for integrating the output signal of space based infrared detectors, said method comprising the steps of:

  • a) receiving the output signal of an infrared detector at an input port;

    b) simultaneously communicating the detector output signal to first and second integration circuits;

    c) integrating the detector output signal over a first time interval with the first integration circuit;

    d) simultaneously integrating the detector output signal over a second time interval with the second integration circuit, the second time interval being longer that the first time interval;

    e) latching a first counter at a first counter value when a first reference ramp signal achieves a preset value relative to the integrated value of the detector output in the first integration circuit;

    f) outputting the latched first counter value as a digital signal representative of the detector output signal in response to saturation of the second integration circuit;

    g) latching a second counter at a second counter value when a second reference ramp signal achieves a preset value relative to the integrated value of the detector output in the second integration circuit in response to non-saturation of the second integration circuit;

    h) overwriting the first counter value with the second counter value in further response to non-saturation of the second integration circuit; and

    i) outputting the latched second counter value as a digital signal representative of the detector output signal in further response to non-saturation of the second integration circuit.

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