3D THERMAL DETECTION CIRCUITS AND METHODS

• US 20150110158A1
• Filed: 10/17/2013
• Published: 04/23/2015
• Est. Priority Date: 10/17/2013
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: LIU, Szu-Lin, HORNG, Jaw-Juinn, PENG, Yung-Chow
• Granted Patent: US 9,599,517 B2
• Time in Patent Office: Days
• US Class Current: 374/184
• CPC Class Codes: G01K 7/20 in a specially-adapted circuit, e.g. bridge circuit
• CPC Class Codes: G01K 7/21 for modifying the output characteristic, e.g. linearising

Abstract

A circuit includes sensing circuitry including at least one sensing element configured to output at least one temperature-dependent voltage. A compare circuit is configured to generate at least one intermediate voltage in response to comparing the at least one temperature-dependent voltage to a feedback voltage. A control circuit is configured to generate at least one control signal in response to the intermediate voltage. A switching circuit is configured to couple a capacitor coupled to a feedback node to one of a first voltage supply and a second voltage supply in response to the at least one control signal to generate an output signal having a pulse width that is based on a temperature sensed by the sensing circuitry.

Claims

1. A circuit, comprising:

sensing circuitry including at least one sensing element configured to output at least one temperature-dependent voltage;

a compare circuit configured to generate at least one intermediate voltage in response to comparing the at least one temperature-dependent voltage to a feedback voltage;

a control circuit configured to generate at least one control signal in response to the intermediate voltage; and

a switching circuit configured to couple a capacitor coupled to a feedback node to one of a first voltage supply and a second voltage supply in response to the at least one control signal to generate an output signal having a pulse width that is based on a temperature sensed by the sensing circuitry.

2. The circuit of claim 1, wherein one of the at least one sensing element is disposed on a first layer of a three-dimensional integrated circuit, and wherein the compare circuit, the control circuit, and the switching circuit are disposed on a second layer of the three-dimensional integrated circuit.

3. The circuit of claim 1, wherein the at least one sensing element includes at least one resistor having a resistance that is based on a temperature of the at least one resistor.

4. The circuit of claim 1, wherein the control circuit includes a latch configured to receive a pair of intermediate voltages from the compare circuit and to output a pair of control signals in response.

5. The circuit of claim 4, wherein the switching circuit includes

a first transistor having a source coupled to the first power supply, a drain coupled to the feedback node, and a gate configured to receive one of the control signals output from the control circuit;

and

a second transistor having a source coupled to the second power supply, a drain coupled to the feedback node, and a gate configured to receive another of the control signals output from the control circuit.

6. The circuit of claim 5, wherein the compare circuit includes

a first comparator having a first input configured to receive a first temperature-dependent voltage from the sensing circuitry and a second input configured to receive the feedback voltage from the feedback node;

and

a second comparator having a first input configured to receive a second temperature-dependent voltage from the sensing circuitry and a second input configured to receive the feedback voltage from the feedback node.

7. The circuit of claim 6, wherein the at least one sensing circuitry includes

a first switch coupled to a first node disposed between a power supply node and the resistor, the first switch configured to couple the first node to the first input of the first comparator;

and

a second switch coupled to a second node disposed between the resistor and a second resistor, the second switch configured to couple the second node to the first input of the second comparator.

8. The circuit of claim 1, wherein the capacitor is a temperature insensitive capacitor.

9. A method, comprising:

sensing a temperature at a first sensing element and outputting at least one temperature-dependent voltage in response;

outputting at least one intermediate voltage from a compare circuit in response to comparing the at least one temperature-dependent voltage to a feedback voltage;

selectively charging and discharging a capacitor coupled to a feedback node in response to at least one control signal that is based on the at least one temperature-dependent voltage; and

outputting a signal having a pulse-width that is based on the temperature at the first sensing element.

10. The method of claim 9, wherein selectively charging and discharging the capacitor includes coupling the feedback node to one of a first voltage source and a second voltage source.

11. The method of claim 9, wherein the sensing element is disposed on a first layer of a three-dimensional integrated circuit and is coupled to other circuitry disposed on a second layer of a three-dimensional integrated circuit by a via.

12. A three-dimensional integrated circuit, comprising:

a first layer including at least one sensing element configured to output at least one temperature-dependent voltage; and

a second layer disposed vertically with respect to the first layer and coupled to the first layer by at least one via, the second layer including

a compare circuit configured to generate at least one intermediate voltage in response to comparing the at least one temperature-dependent voltage to a feedback voltage;

a control circuit configured to generate at least one control signal in response to the intermediate voltage; and

a switching circuit configured to couple a capacitor coupled to a feedback node to one of a first voltage supply and a second voltage supply in response to the at least one control signal to generate an output signal having a pulse width that is based on a temperature sensed by the sensing circuitry.

13. The circuit of claim 12, further comprising a plurality of layers disposed vertically with respect to the first layer, each of the plurality of layers includes at least one respective sensing element configured to output at least one temperature-dependent voltage.

14. The circuit of claim 12, wherein the at least one sensing element includes at least one resistor having a resistance that is based on a temperature of the at least one resistor.

15. The circuit of claim 12, wherein the control circuit includes a latch configured to receive a pair of intermediate voltages from the compare circuit and to output a pair of control signals in response.

16. The circuit of claim 15, wherein the switching circuit includes

a first transistor having a source coupled to the first power supply, a drain coupled to the feedback node, and a gate configured to receive one of the control signals output from the control circuit;

and

a second transistor having a source coupled to the second power supply, a drain coupled to the feedback node, and a gate configured to receive another of the control signals output from the control circuit.

17. The circuit of claim 16, wherein the compare circuit includes

a first comparator having a first input configured to receive a first temperature-dependent voltage from the sensing circuitry and a second input configured to receive the feedback voltage from the feedback node;

and

a second comparator having a first input configured to receive a second temperature-dependent voltage from the sensing circuitry and a second input configured to receive the feedback voltage from the feedback node.

18. The circuit of claim 17, wherein the at least one sensing circuitry includes

a first switch coupled to a first node disposed between a power supply node and the resistor, the first switch configured to couple the first node to the first input of the first comparator;

and

a second switch coupled to a second node disposed between the resistor and a second resistor, the second switch configured to couple the second node to the first input of the second comparator.

19. The circuit of claim 12, wherein the capacitor is a temperature insensitive capacitor.

20. The circuit of claim 12, wherein the first and second layers each include a respective substrate and interconnect, and wherein the at least one sensing element is disposed within the substrate or interconnect of the first layer.