Patent ID: 7928882

Claim:
An integrated circuit comprising: a successive approximation analog to digital conversion circuit, comprising a plurality of sensing circuits for sensing analog physical operating parameters of the integrated circuit that represent different characteristics of the integrated circuit and forming sensing results that indicate whether values of the analog physical operating parameters are above or below reference values of parameters represented by digital approximation data, respectively, and an update circuit for making successive updates to the digital approximation data dependent on the sensing results, so that the successively updated digital approximation data converges to digital values that substantially represent the analog physical operating parameters; a serial shift register circuit comprising serially connected shift registers, wherein the serial shift register circuit has parallel outputs coupled to the plurality of sensing circuits for supplying the digital approximation data, parallel inputs coupled to the plurality of sensing circuits for receiving the sensing results, and parallel inputs/outputs coupled to the update circuit for supplying the sensing results and updating the digital approximation data for respective ones of the sensing circuits successively, whereby the update circuit is shared by the plurality of sensing circuits using the serially connected shift registers, wherein the update circuit updates digital numbers that represent the reference values of parameters one after another dependent on respective ones of the sensing results that are formed by the plurality of sensing circuits, so that each digital number is part of a respective series of updated numbers that converges to a value that approximates a representation of a respective one of the analog physical operating parameters.