초록 ▼

Various systems and methods for temperature measurement are disclosed. For example, some embodiments of the present invention provide temperature measurement systems. Such temperature measurement systems include a variable current source and a diode connected transistor. The variable current source

Various systems and methods for temperature measurement are disclosed. For example, some embodiments of the present invention provide temperature measurement systems. Such temperature measurement systems include a variable current source and a diode connected transistor. The variable current source is capable of applying two or more distinct currents to the diode connected transistor. The currents result in a different base-emitter voltage on the diode connected transistor. The systems further include an n-factor coefficient register and an analog to digital converter. The analog to digital converter is operable to receive two of the base-emitter voltages created by applying the different currents, and to provide a digital output based at least in part on a value stored in the n-factor coefficient register and the two base-emitter voltages.

대표청구항 ▼

What is claimed is: 1. A temperature measurement system, wherein the temperature measurement system comprises: a variable current source that is operable to provide a first current and a second current; a transistor that is electrically coupled to the variable current source, wherein a first base-e

What is claimed is: 1. A temperature measurement system, wherein the temperature measurement system comprises: a variable current source that is operable to provide a first current and a second current; a transistor that is electrically coupled to the variable current source, wherein a first base-emitter voltage occurs when the first current is applied to the transistor, and wherein a second base-emitter voltage occurs when the second current is applied to the transistor; an n-factor coefficient register that stores an n-factor adjustment, wherein the n-factor adjustment is based at least in part on a difference between a first temperature from an external measurement sensor and a second temperature calculated using the first and second base-emitter voltages; an adder that is coupled to the n-factor coefficient register, wherein the adder combines a standard n-factor with the n-factor adjustment to generate a corrected n-factor; and an analog to digital converter (ADC) that is coupled to the adder and to the transistor, wherein the ADC is operable to receive the first base-emitter voltage and the second base-emitter voltage, and wherein the ADC is operable to provide a digital output based at least in part on the corrected n-factor, the first base-emitter voltage, and the second base-emitter voltage. 2. The temperature measurement system of claim 1, wherein the transistor is diode connected. 3. The temperature measurement system of claim 1, wherein the temperature measurement circuit further comprises a temperature calculation module that is operable to calculate a temperature based on the digital output. 4. The temperature measurement system of claim 1, wherein the ADC is operable to perform a number of samples corresponding to the value stored in the n-factor coefficient register. 5. The temperature measurement system of claim 1, wherein the n-factor coefficient register is accessible via a two wire interface. 6. The temperature measurement system of claim 5, wherein the two wire interface includes a data line and a clock line. 7. The temperature measurement system of claim 1, wherein the gain of the ADC corresponds to the corrected n-factor. 8. The temperature measurement system of claim 7, wherein the ADC is a first order integrating converter, and wherein the number of samples processed by the first order integrating converter is controlled at least in part based on the value stored in the n-factor coefficient register. 9. The temperature measurement system of claim 8, wherein an ideal gain of the first order integrating converter is approximately three hundred. 10. The temperature measurement system of claim 8, wherein the first order integrating converter is a differential ADC. 11. A method for comprising: providing a temperature measurement circuit; determining a temperature error of a temperature reported by the measurement circuit, by: operating the temperature measurement circuit using a standard n-factor value; measuring a first temperature of the temperature measurement circuit using an external measurement sensor; calculating a second temperature of the temperature measurement circuit using a first base-emitter voltage and a second base-emitter voltage; calculating a difference between the first temperature and the second temperature; determining an n-factor adjustment to compensate for the temperature error based on the difference; and writing the n-factor adjustment to an n-factor coefficient register. 12. The method of claim 11, wherein the step of operating the temperature measurement circuit using a standard n-factor value further comprises operating the circuit with a zero value in the n-factor coefficient register. 13. The method of claim 11, wherein the step of operating the temperature measurement circuit using a standard n-factor value further comprises operating the circuit with the standard n-factor value in the n-factor coefficient register. 14. The method of claim 11, wherein the gain of an analog to digital converter corresponds to the n-factor adjustment. 15. The method of claim 14, wherein the n-factor adjustment is combined with the standard n-factor value, and wherein the combined value governs the gain of the analog to digital converter. 16. An apparatus comprising: a variable current source that provides a first current and a second current; a transistor that is electrically coupled to the variable current source, wherein a first base-emitter voltage occurs when the first current is applied to the transistor, and wherein a second base-emitter voltage occurs when the second current is applied to the transistor; an n-factor coefficient register that stores an n-factor adjustment, wherein the n-factor adjustment is based at least in part on a difference between a first temperature from an external measurement sensor and a second temperature calculated using the first and second base-emitter voltages; an first adder that is coupled to the n-factor coefficient register, wherein the adder combines a standard n-factor with the n-factor adjustment to generate a corrected n-factor; an ADC including: a first switch that is coupled to the base of the transistor; a second switch that is coupled to the collector of the transistor; an amplifier; a capacitor that is coupled between the first and second switches and the amplifier; a comparator that is coupled to the amplifier and that receives a reference voltage; a second adder that is coupled to the comparator; a first counter that is coupled to the second adder; a second counter that is coupled to the first adder and the first counter; and a result register that is coupled to the first and second counters; and temperature calculation circuitry that is coupled to the result register. 17. The apparatus of claim 16, wherein the ADC further comprises: a third switch that receives the reference voltage; a fourth switch that is coupled to ground; a second capacitor that is coupled to the third and fourth switches and that is coupled to the amplifier; a fifth switch that is coupled between the second capacitor and the comparator; a sixth switch that is coupled to the second capacitor; a third capacitor that is coupled between the sixth switch and the comparator. 18. The apparatus of claim 16, wherein the transistor is diode connected.