US 2024/0201024 A1 · INTEGRATED CIRCUIT COMPRISING A TEMPERATURE SENSOR

Abstract

An integrated circuit temperature sensor includes two diode-connected bipolar transistors having different sizes. A switching circuit selectively applies the base-emitter voltages generated across the two diode-connected bipolar transistors to the input of a buffer circuit. A control unit controls alternate switching by the switching circuit. An analog-to-digital converter has an input connected to an output of the buffer circuit. The analog-to-digital converter calculates a numeric value corresponding to a difference between the voltages generated across the two diode-connected bipolar transistors, this difference in voltages being proportional to absolute temperature.

Claims18

Dependent claims

An integrated circuit, comprising a temperature sensor that includes:

first and second diode-connected transistors having different sizes;
a buffer circuit;
a switching circuit;
a control unit configured to control the switching circuit to successively apply a voltage generated across the first diode-connected transistor and a voltage generated across the second diode-connected transistor to an input of the buffer circuit;
an analog-to-digital converter having an input connected to an output of the buffer circuit, the analog-to-digital converter configured to successively convert voltages output from the buffer circuit into numeric voltage values corresponding to the voltages generated across the first and second diode-connected transistors and to calculate a numeric value corresponding to a difference between the numeric values, wherein the numeric value is proportional to absolute temperature and independent of offset voltages of the analog-to-digital converter and the buffer circuit.

2 more elements

An integrated circuit temperature sensor, comprising:

a bandgap circuit comprising:
a first diode-connected bipolar transistor;
a second diode-connected bipolar transistor;
an operational amplifier having an inverting input connected to an emitter of the first diode-connected bipolar transistor and a non-inverting input connected to an emitter of the second diode-connected bipolar transistor via a resistor;
a first PMOS-type transistor having a gate connected to an output of the operational amplifier and a drain connected to the inverting input of the operational amplifier and to the emitter of the first bipolar transistor;
and
a second PMOS-type transistor having a gate connected to an output of the operational amplifier and a drain connected to the non-inverting input of the operational amplifier and to the emitter of the second bipolar transistor via the resistor;
a temperature sensitive circuit comprising:
a third PMOS-type transistor and a third diode-connected bipolar transistor, the third PMOS-type transistor having a gate connected to the output of the operational amplifier and a drain connected to an emitter of the third diode-connected bipolar transistor;
and
a fourth PMOS-type transistor and a fourth diode-connected bipolar transistor, the fourth PMOS-type transistor having a gate connected to the output of the operational amplifier and a drain connected to an emitter of the fourth diode-connected bipolar transistor;
a sampling circuit configured to alternately sample base-emitter voltages of the third and fourth diode-connected bipolar transistors;
and
an analog-to-digital converter circuit configured to convert the alternately sampled base-emitter voltages into numeric voltage values and to calculate a numeric value corresponding to a difference between the numeric values, wherein the numeric value is proportional to absolute temperature.

11 more elements

Dependencies are inferred from the claim text.

Integrated circuit comprising a temperature sensor

Life of this patent

Integrated circuit comprising a temperature sensor

Life of this patent

Abstract

Claims18