Integrating capacitively coupled transimpedance amplifier

An amplifier circuit for an infrared detector array fabricated on a large scale integrated structure, said amplifier circuit comprising:

• biasing means, separate from said detector, for biasing said detector,
• switching means, fabricated on said large scale integrated structure, connected between said biasing means and said detector, for selectively coupling said biasing means to said detector during a first time period and for decoupling said biasing means from said detector during a second time period,
• amplifying means, connected to an output terminal of said detector, fabricated on said large scale integrated structure, for amplifying an output signal of said detector during said second time period, and
• output means for providing a voltage proportional to an output signal of said amplifying means, connected to an output terminal of said amplifying means, comprising:
• a capacitive element;
• and
• voltage controlling means responsive to a voltage output of said amplifying means for controlling a voltage on said capacitive element.

An amplifier circuit for an infrared detector array fabricated on a large scale integrated structure, said amplifier circuit comprising:

• biasing means, separate from said detector, for biasing said detector,
• switching means, fabricated on said large scale integrated structure, connected between said biasing means and said detector, for selectively coupling said biasing means to said detector during a first time period and for decoupling said biasing means from said detector during a second time period,
• amplifying means, connected to an output terminal of said detector, fabricated on said large scale integrated structure, for amplifying an output signal of said detector during said second time period, and
• output means for providing a voltage proportional to an output signal of said amplifying means, connected to an output terminal of said amplifying means, comprising:
• a first capacitive element,
• a second capacitive element having a capacitance less than that of said first capacitive element,
• charging means for periodically charging and draining said first and second capacitive elements, connected individually to said first and second capacitive elements, and
• transfer means, bridging said capacitive elements, for controlling the flow of charge between said first and second capacitive elements in accordance with said output signal of said amplifying means wherein a charge is stored on said first capacitive element proportional to said output signal of said amplifying means and then transfered to said second capacitive element.