Patent ID: 7612702

Claim:
An analog to digital converter comprising: a digital to analog converter for outputting an analog voltage; a data storage device; a digital ramp generator comprising a first counter for outputting an incremental code based upon a clock signal, said first counter varying the incremental code by an incremental step based upon the clock signal, and a second counter for receiving the incremental code from said first counter, and for outputting a digital ramp code that varies based on the incremental code, the digital ramp code being provided to respective inputs of said digital to analog converter and to said data storage device; an analog voltage comparator having a first input for receiving the analog voltage from said digital to analog converter, and a second input for receiving an input voltage, said analog voltage comparator switching logic states when the analog voltage received at the first input equals the input voltage received at the second input; and said data storage device for storing the digital ramp code at the switching of the logic state of said analog voltage comparator.