초록 ▼

A temperature sensor circuit generates an output voltage that is linearly proportional to temperature over a desired temperature range with a desired offset voltage. The temperature sensor includes two Proportional To Absolute Temperature (PTAT) current sources that generate PTAT currents and two tr

A temperature sensor circuit generates an output voltage that is linearly proportional to temperature over a desired temperature range with a desired offset voltage. The temperature sensor includes two Proportional To Absolute Temperature (PTAT) current sources that generate PTAT currents and two transistors which conduct the PTAT currents with different current densities to establish a basic voltage PTAT across a resistor. An offset resistor coupled between the bases of the two transistors and a circuit node, shifts the basic PTAT voltage by an offset voltage. A first gain circuit couples to the collector of the first transistor and the offset resistor and generates a servo current (i.e., a current that tends to move the circuit to the desired state by correcting an error) to servo the base of the first transistor when there is a difference between the first transistor's collector current and the PTAT current. A second gain circuit generates a second servo current to servo the emitter of the second transistor when there is a difference between the second transistor's collector current and the PTAT current. These servo currents drive the two transistors such that the second gain circuit generates a temperature related output voltage shifted from the basic voltage PTAT by the offset voltage, and which follows a predetermined temperature scale and has a substantially linear function with a desired offset temperature.

대표청구항 ▼

[ What is claimed is:] [1.] An apparatus including a temperature sensor, the temperature sensor comprising:first and second Proportional To Absolute Temperature (PTAT) current sources that generate first and second PTAT currentsa first resistive circuit coupled to a circuit node;first and second tra

[ What is claimed is:] [1.] An apparatus including a temperature sensor, the temperature sensor comprising:first and second Proportional To Absolute Temperature (PTAT) current sources that generate first and second PTAT currentsa first resistive circuit coupled to a circuit node;first and second transistors coupled to the first and second PTAT current sources respectively, the second transistor coupled to the first resistive circuit, and the first and second transistors configured to conduct first and second currents respectively with different current densities to establish a basic voltage PTAT across the first resistive circuit;a second resistive circuit coupled to the first and second transistors and the circuit node;a first gain circuit coupled between the first transistor and the second resistive circuit and configured to receive a difference between the first PTAT current and the first current through the first transistor and in accordance therewith generate a first servo current which is proportional to a voltage across the second resistive circuit; anda second gain circuit coupled to the second transistor and configured to receive a first signal responsive to a difference between the second current through the second transistor and the second PTAT current and in accordance therewith generate a second servo current,wherein the first and second servo currents drive the first and second transistors respectively such that the second gain circuit generates a temperature related output voltage which follows a predetermined temperature scale and has a substantially linear function with a desired offset temperature.