AM chirp LADAR readout circuit and module

Abstract

A readout circuit is disclosed for use in an AM chirp LADAR system. The circuit comprises a photodetector such as a metal-semiconductor-metal detector coupled to a passive electronic filter. The filter output coupled to a capacitive-coupled transimpedance amplifier with an output coupled to an analog storage register. The analog storage register output is coupled to a sample-and-hold circuit which in turn is coupled to a sample and hold circuit. The output of the sample and hold circuit is digitized by an analog-to-digital converter circuit for further processing. The circuit may be used as a cell for the readout of an individual pixel on a photodetector or a plurality of cells used in a stack of integrated circuit chips for the read out of a plurality of pixels in a photodetector array. Each IC layer in the stacked photodetector imaging module of the invention is identical to its mates and has a unit cell comprised of a capacitance coupled transimpedance amplifier and analog storage register for receiving the output of a pixel in a detector array. The IC layers share one or more common busses on the module surface opposite the detector array. The common bus carries common signals such as power, clocks, and control signals. In the stacked configuration, each IC operates independently and outputs its signals on a unique output line. The stacked ICs operate under the same set of control vectors as the individual ICs comprising the stack. No communication is required between layers, simplifying the design and control process.

Dependencies are inferred from the claim text.