TEMPERATURE SENSOR FOR MEASURING THERMISTOR RESISTENCE

• US 20180035889A1
• Filed: 08/05/2016
• Published: 02/08/2018
• Est. Priority Date: 08/05/2016
• Status: Active Grant

• Current Assignee: Vital Connect, Inc.
• Original Assignee: Vital Connect, Inc.
• Inventors: LIOU, Raymond, AGA, Arshan, FANG, Steve
• Granted Patent: US 10,582,854 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 2562/0276 comprising a thermosensitive compound
• CPC Class Codes: A61B 5/0008 Temperature signals
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: G01K 1/024 for remote indication
• CPC Class Codes: G01K 7/24 in a specially-adapted circuit, e.g. bridge circuit

Abstract

A method and system for determining thermistor resistance have been disclosed. The method comprises providing a temperature sensor network within a wireless sensor device, wherein the temperature sensor network includes a driver device and a receiver device, coupling the driver device to the receiver device using a dual bond wire system, determining at least one output voltage using at least one input current flowing through the dual bond wire system, and determining the thermistor resistance using the at least one output voltage. The system comprises a wireless sensor device including a temperature sensor network that comprises driver and receiver devices, and a dual bond wire system that couples the driver device to the receiver device, wherein at least one output voltage is determined using at least one input current flowing through the dual bond wire system, further wherein the thermistor resistance is determined using the at least one output voltage.

Claims

1. A method for determining thermistor resistance, the method comprising:

providing a temperature sensor network within a wireless sensor device, wherein the temperature sensor network includes a driver device and a receiver device;

coupling the driver device to the receiver device using a dual bond wire system;

determining at least one output voltage using at least one input current flowing through the dual bond wire system; and

determining the thermistor resistance using the at least one output voltage.

2. The method of claim 1, wherein the determining of the least one output voltage is done prior to digitization by an analog-to-digital converter (ADC) coupled to the receiver device.

3. The method of claim 1, wherein the dual bond wire system comprises a first set of bond wires coupled to the driver device and a second set of bond wires coupled to the receiver device, further wherein the at least one input current passes through the first set of bond wires but does not pass through the second set of bond wires.

4. The method of claim 3, wherein one of the first set of bond wires is coupled to one of the second set of bond wires and the other of the first set of bond wires is coupled to the other of the second set of bond wires.

5. The method of claim 3, further comprising:

determining an input voltage using a plurality of switches across the first set of bond wires and measuring an offset voltage across the second set of bond wires.

6. The method of claim 5, wherein the plurality of switches comprises a first switch, a second switch, and a third switch.

7. The method of claim 6, wherein the input voltage comprises a first input voltage and a second input voltage.

8. The method of claim 7, further comprising:

determining the first input voltage when each of the first switch, the second switch, and the third switch are turned off; and

determining the second input voltage when both the first switch and the third switch are turned on, and when the second switch is turned off.

9. The method of claim 8, wherein the at least one output voltage comprises a first output voltage and a second output voltage.

10. The method of claim 9, wherein the first output voltage is determined using the first input voltage, the offset voltage, and a gain of the receiver device and the second output voltage is determined using the second input voltage, the offset voltage, and the gain of the receiver device.

11. The method of claim 6, wherein the input voltage comprises a first input voltage, a second input voltage, a third input voltage, and a fourth input voltage.

12. The method of claim 11, further comprising:

determining the first input voltage when each of the first switch, the second switch, and the third switch are turned off;

determining the second input voltage when the first switch is turned on, and when both the second switch and the third switch are turned off;

determining the third input voltage when the second switch is turned on, and when both the first switch and the third switch are turned off; and

determining the fourth input voltage when both the first switch and the third switch are turned on, and when the second switch is turned off.

13. The method of claim 12, wherein the at least one output voltage comprises a first output voltage, a second output voltage, a third output voltage, and a fourth output voltage.

14. The method of claim 13, wherein the first output voltage is determined using the first input voltage, the offset voltage, and a gain of the receiver device, the second output voltage is determined using the second input voltage, the offset voltage, and the gain of the receiver device, the third output voltage is determined using the third input voltage, the offset voltage, and the gain of the receiver device, and the fourth output voltage is determined using the fourth input voltage, the offset voltage, and the gain of the receiver device.

15. The method of claim 1, further comprising:

amplifying the at least one output voltage prior to determining the thermistor resistance; and

dithering the at least one amplified output voltage, wherein the at least one amplified output voltage is used to determine the thermistor resistance.

16. The method of claim 11, wherein the dithering further comprises:

applying a plurality of small voltages to the at least one amplified output voltage.

17. The method of claim 16, wherein the plurality of small voltages cover a range of a predetermined least significant bit (LSB) of an analog-to-digital converter (ADC).

18. The method of claim 17, wherein the predetermined LSB is 1 LSB of the ADC.

19. A system for determining thermistor resistance, the system comprising:

a temperature sensor network within a wireless sensor device, wherein the temperature sensor network includes a driver device and a receiver device; and

a dual bond wire system that couples the driver device to the receiver device, wherein at least one output voltage is determined using at least one input current flowing through the dual bond wire system, further wherein the thermistor resistance is determined using the at least one output voltage.

20. The system of claim 19, wherein the dual bond wire system comprises a first set of bond wires coupled to the driver device and a second set of bond wires coupled to the receiver device, further wherein the at least one input current passes through the first set of bond wires but does not pass through the second set of bond wires.