Digital readout method and apparatus

Abstract

Autonomously operating analog to digital converters are formed into a two dimensional array. The array may incorporate digital signal processing functionality. Such an array is particularly well-suited for operation as a readout integrated circuit and in combination with a sensor array, forms a digital focal plane array.

What is claimed is: 
     
         1 . An apparatus comprising:
 a sensor array comprising a sensor to generate an analog signal;   an analog-to-digital converter (ADC) array comprising an ADC operably coupled to the sensor, the ADC comprising a capacitance to be charged by the signal, the capacitance defining a least significant bit (LSB) of the ADC and configured to convert the analog signal into digital data; and   transfer circuitry, operably coupled to the ADC array, to transfer the digital data among ADCs in the ADC array synchronously with motion of an image across the sensor array,   wherein the ADC comprises a counter to store at least a portion of the digital data as a digital number and to increment and/or decrement the digital number in response to digital data transferred from another ADC in the ADC array.