Temperature sensing with feedback digital-analog converter (DAC) of delta-sigma modulator

摘要

Apparatus and method are disclosed where a delta-sigma modulator may be used to generate temperature information within an integrated circuit. The delta-sigma modulator may include a loop filter 304, a quantizer 306, and a feedback digital-to-analog converter (DAC) 302 coupled to a summation element 310. Temperature sensing elements may be incorporated into the feedback DAC of the delta-sigma modulator. Temperature information is then processed in the loop filter of the delta-sigma modulator and output in an average voltage value of a digital signal output from the delta-sigma modulator. The temperature sensing element may comprise first and second proportional to absolute temperature PTAT sources and a bipolar junction transistor BJT.