Patent ID: 11892360
Assignee: STMICROELECTRON NTERNATIONAL N.V.
Field: Basic communication processes (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 11:
12. A temperature sensing circuit, comprising:
a voltage generation circuitry comprising:
first and second bipolar junction transistors having coupled collectors and bases, and biased at different current densities;
a third bipolar junction transistor having its collector coupled to its base, the third bipolar junction transistor biased by a calibrated current and having a base-emitter voltage that is a voltage complementary to absolute temperature, the voltage complementary to absolute temperature having a curved non-linearity across temperature; and
fourth and fifth bipolar junction transistors having coupled collectors and bases, the fifth bipolar junction transistor biased by a temperature independent constant current, the fourth bipolar junction transistor biased by a current proportional to absolute temperature;

a switched capacitor circuit configured to selectively sample voltages produced by the voltage generation circuitry and provide the sampled voltages to inputs of an integrator; and
a quantization circuit configured to quantize outputs of the integrator to produce a bitstream;
wherein the switched capacitor circuit cooperates with the integrator under control of the bitstream to cause integration of a difference between a base-emitter voltage of the first bipolar junction transistor and a base-emitter voltage of the second bipolar junction transistor to thereby produce a voltage proportional to absolute temperature, or cause integration of a difference between a base-emitter voltage of the fourth bipolar junction transistor and a sum of the voltage complementary to absolute temperature and a base-emitter voltage of the fifth bipolar junction transistor to thereby produce a negative voltage complementary to absolute temperature having negligible non-linearity across temperature.