Raytheon Company

Hughes Aircraft Company

Mark V Martin

John J Drab

Norman C Lee

Raymond Kwok

David L LeFevre

A differential capacitance sense amplifier capable of measuring a small difference-signal capacitance in the presence of circuit mismatches and large unequal interconnect capacitances. The sense amplifier includes three sections: a common-mode section applies a 'read' voltage to two capacitors in a manner that rejects unequal interconnect capacitance, a difference-mode section generates a signal proportional to the capacitance difference between the two capacitors, and an offset-canceling section compensates for circuit mismatches in the difference-mode section. The amplifier can be adapted for use as a sense amplifier for a ferroelectric differential capacitance memory unit.

Differential capacitance sense amplifier

Auto correction algorithm for piece-wise linear circuits

Apparatus and methods are disclosed for providing a low power, low noise preamplifier, especially useful with a Forward Looking Infrared (FLIR) sensor array. Utilizing a differential amplifier, where one half of the differential pair is shared among a plurality of channels, the power consumption of the amplifier is effectively reduced. Such an arrangement also eliminates the need for bulky coupling capacitors used in ac-coupled, single ended amplifiers. In addition, cross-talk between sensor outputs caused by detector ground impedance is reduced.

Low power, low noise preamplifier with offset voltage cancellation

Growing community of inventors

Redondo Beach, CA, United States of America

Mark V Martin