Increasing power supply noise rejection using linear voltage regulators in an on-chip temperature sensor

• US 20030155964A1
• Filed: 02/19/2002
• Published: 08/21/2003
• Est. Priority Date: 02/19/2002
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Liu, Dean, Gauthier, Claude, Gold, Spencer, Amick, Brian, Zarrineh, Kamran, Trivedi, Pradeep
• Granted Patent: US 6,809,557 B2
• Time in Patent Office: Days
• US Class Current: 327/540
• CPC Class Codes: G05F 1/467 Sources with noise compensation

Abstract

An apparatus that uses a linear voltage regulator to reject power supply noise in a temperature sensor is provided. Further, a method for using a linear voltage regulator to reject power supply noise in a temperature sensor is provided. Further, a method and apparatus that uses a differential amplifier with a source-follower output stage as a linear voltage regulator for a temperature sensor is provided.

Claims

1. An integrated circuit having a temperature sensor disposed thereon, the temperature sensor comprising:

a voltage generator that outputs a voltage representative of a temperature on the integrated circuit;

a voltage regulator that uses feedback to decouple power supply noise from the voltage; and

a voltage-to-frequency converter that generates a frequency using the voltage as a control voltage for the voltage-to-frequency converter, wherein the frequency is representative of the temperature.

2. The integrated circuit of claim 1, wherein the voltage regulator is a linear voltage regulator, and wherein the linear voltage regulator is a differential amplifier with a source follower output.

3. The integrated circuit of claim 2, wherein the differential amplifier stage comprises a differential amplifier that generates the differential voltage.

4. The integrated circuit of claim 2, wherein the output stage decreases the output resistance of the differential amplifier stage.

5. The integrated circuit of claim 2, the output stage comprising:

a source follower that inputs the differential voltage, wherein the source follower generates an output voltage

6. The integrated circuit of claim 5, wherein the linear voltage regulator buffers the voltage output from the voltage generator, and wherein the buffered power supply voltage is operatively connected to the output voltage by a loaded feedback path.

7. The integrated circuit of claim 6, wherein the buffered power supply voltage is operatively connected to the voltage signal through a feedback path.

8. The integrated circuit of claim 1, wherein the differential amplifier stage removes noise from the voltage signal.

9. An apparatus for rejecting power supply noise on a voltage signal generated by a voltage generator, comprising:

means for generating a differential voltage in relation to the voltage signal;

means for generating an output voltage based on the differential voltage; and

means for generating a buffered power supply voltage in relation to the output voltage.

10. A method for rejecting power supply noise on a voltage signal generated by a voltage generator, comprising:

generating an output voltage based on a differential voltage, wherein the output voltage is generated by an output stage; and

generating a buffered power supply voltage in relation to the output voltage, wherein the buffered power supply voltage is generated by the output stage.

11. The method of claim 10, wherein the buffered power supply voltage is sensitive to temperature.

12. The method of claim 10, wherein the buffered power supply voltage is insensitive to temperature.

13. The method of claim 10, wherein the buffered power supply voltage is regulated using feedback.