High frequency voltage supply monitor

Patent metadata

Field	Value
Publication number	US-9568511-B2
Application number	US-201414208408-A
Country	US
Kind code	B2
Filing date	Mar 13, 2014
Priority date	Mar 13, 2014
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

Various aspects provide a high frequency voltage supply monitor capable of monitoring high frequency variations of the voltage supply inside a microelectronic circuit substantially in real time. The voltage supply monitor can comprise a differential amplifier circuit having a substantially constant gain over a wide bandwidth, allowing the supply voltage variations to be amplified according to a known gain under a wide range of conditions. The amplified signal can then be sent to an output port for monitoring and measurement by an external display device.

First claim

What is claimed is:

1. A system for monitoring voltage variations, comprising:
a differential amplifier circuit comprising a high-pass filter configured to generate a signal in response to detection of a voltage variation that exceeds a defined frequency on a power supply rail of a microelectronic circuit, the differential amplifier circuit further comprising a differential amplifier that amplifies the signal from the high-pass filter to yield an amplified signal representing the voltage variation, wherein a first input of the differential amplifier circuit and a second input of the differential amplifier circuit are electrically connected to a common mode voltage via respective resistors, and wherein the common mode voltage is substantially equal to a nominal voltage of the power supply rail; and
a compensation component connected to the differential amplifier circuit and one or more components of the microelectronic circuit, the compensation component configured to, in response to receiving a signal from the differential amplifier circuit indicating that the amplified signal indicates a high frequency oscillation on the power supply rail, initiate a countermeasure that modifies a behavior of the one or more components of the microelectronic circuit, wherein the countermeasure comprises at least one of disablement the one or more components of the microelectronic circuit or reduction of an activity rate of the one or more components of the microelectronic circuit.

2. The system of claim 1 , wherein the high-pass filter comprises at least one capacitor and at least one resistor that couple the power supply rail to the differential amplifier circuit.

3. The system of claim 1 , wherein the differential amplifier circuit comprises a degenerative differential pair circuit having a substantially constant gain over a defined bandwidth.

4. The system of claim 2 , further comprising one or more termination resistors connected between output lines of the differential amplifier circuit and the power supply rail.

5. The system of claim 1 , further comprising a logging component configured to store a record of the amplified signal in a local memory or an external memory in response to detecting that a high frequency voltage oscillation represented by the amplified signal exceeds the defined frequency.

6. A method for detecting high frequency voltage variations, comprising:
detecting, at an input of a high-pass filter of a differential amplifier circuit comprising the high-pass filter and a differential amplifier, a voltage variation on a power supply rail of a microelectronic circuit, wherein a first input of the differential amplifier circuit and a second input of the differential amplifier circuit are electrically connected to a common mode voltage via respective resistors, and wherein the common mode voltage is substantially equal to a nominal voltage of the power supply rail;
generating, at an output of the high-pass filter, a signal based on the voltage variation;
amplifying, by the differential amplifier circuit, the signal to yield an amplified signal representing the voltage variation; and
sending, by the differential amplifier circuit, the amplified signal to a compensation circuit connected to the differential amplifier circuit;
in response to a determination that the amplified signal indicates presence of noise on the power supply rail, initiating, by the compensation circuit, a countermeasure that at least one of disables a component of the microelectronic circuit or curtails an activity rate of the component of the microelectronic circuit, wherein the component of the microelectronic circuit is connected to the compensation circuit.

7. The method of claim 6 , wherein the amplifying comprises amplifying the signal using a degenerative differential pair circuit as the differential amplifier.

8. The method of claim 7 , further comprising matching an impedance of a transmission line that sends the amplified signal to a display device, wherein the matching comprises matching using one or more termination resistors connected between the transmission line and the power supply rail.

9. The method of claim 6 , further comprising logging a record of the voltage variation in a memory based on the amplified signal.

10. A power monitoring system, comprising:
means for monitoring voltage fluctuations on a power supply rail of an integrated circuit using a differential amplifier circuit comprising a high-pass filter and a differential amplifier;
means for biasing an input of the differential amplifier circuit using a common mode voltage that is substantially equal to a nominal voltage of the power supply rail;
means for generating a signal based on the voltage fluctuations;
means for amplifying the signal to yield an amplified signal capable of being measured by a display device; and
means for instructing a compensation circuit connected to the differential amplifier circuit to initiate a countermeasure that at least one of disables a component of the integrated circuit or curtails an activity rate of the component of the integrated circuit in response to a determination that the amplified signal is indicative of a high frequency oscillation on the power supply rail, wherein the compensation circuit is connected to the component of the integrated circuit.

11. The power monitoring system of claim 10 , wherein the means for generating comprises means for generating the signal based on a subset of the voltage fluctuations that exceed a defined frequency.

12. The system of claim 5 , wherein the logging component is configured to store the record of the amplified signal in the local memory or the external memory in response to detecting that the high frequency voltage oscillation represented by the amplified signal has persisted for a defined period of time.

13. The method of claim 9 , wherein the logging comprises logging the record in response to a determination that the voltage variation exceeds a defined frequency.

14. The method of claim 13 , wherein the logging comprises logging the record in response to a determination that the voltage variation has persisted for a defined period of time.

15. The power monitoring system of claim 10 , further comprising means for logging a record of the voltage fluctuations in response to a determination, based on the amplified signal, that the voltage fluctuations exceed a defined frequency.

16. The power monitoring system of claim 15 , wherein the means for logging comprises means for logging the record in response to a determination, based on the amplified signal, that the voltage fluctuations have persisted for a defined period of time.

Assignees

• Applied Micro Circuits Corp

Inventors

• Ravezzi Luca
• Harvard Qawi
• Partovi Hamid

Classifications

• G01R19/16552 Primary

  in I.C. power supplies · CPC title

• G01R19/0007

  Frequency selective voltage or current level measuring (measuring frequency G01R23/00; testing attenuation in line transmission systems H04B3/48; monitoring testing in transmission systems H04B17/00) · CPC title

• G06F1/26

  Power supply means, e.g. regulation thereof (for memories G11C) · CPC title

• G06F1/305

  in the event of power-supply fluctuations · CPC title