Patent ID: 7758240

Claim:
A PN-junction temperature sensing apparatus comprising: a plurality of current sources, wherein each current source comprises a p-type MOSFET transistor being source connected to a supply voltage; a band gap based current reference, which is mirrored in the plurality of current sources; switches having two selectable outputs controlled by a digital processor, wherein each switch is connected with the drain of each current source and wherein a first output of each switch is connected to an anode of a PN-junction thermal sensor and a second output of each switch is connected to an anode of a sink diode and wherein the cathodes of both components are connected to a common level, wherein the number of current sources connected to the switches consists of an odd number of three or more, and wherein each of the current sources exhibits a current gain ratio with respect to the band gap based current reference of 1:1; an integrated A/D converter to digitize the voltage across the PN-junction sensor, wherein the value of the digitized voltage is stored in a memory of the digital processor.