Monitoring (e.g., Failure Detection, Etc.) Patents (Class 327/20)
  • Patent number: 8040156
    Abstract: Provided are a lock detection circuit and a lock detecting method. The lock detection circuit includes two delay devices, four flip-flops and two logic gates, and can accurately detect a lock state of a phase locked loop (PLL) circuit. Therefore, the lock detection circuit can be implemented in a simple structure, and as a result, the lock detection circuit can be compact in size and can consume less electric power. Also, the lock detecting method enables lock detection process to be simpler, so that a lock state can be detected within a short time period.
    Type: Grant
    Filed: May 14, 2009
    Date of Patent: October 18, 2011
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Hui Dong Lee, Kwi Dong Kim, Jong Kee Kwon
  • Patent number: 8032804
    Abstract: Systems and methods are disclosed herein, including those that operate to monitor a first set of operational parameters associated with a memory vault, to adjust a second set of operational parameters associated with the memory vault, and to perform alerting and reporting operations to a host device.
    Type: Grant
    Filed: January 12, 2009
    Date of Patent: October 4, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Joe M. Jeddeloh
  • Patent number: 8018289
    Abstract: A clock circuit includes a phase-lock loop and a holdover circuit. The phase-lock loop generates an output clock signal having a constant frequency based on a loop filter voltage of a loop filter in the phase-lock loop. The holdover circuit generates and stores a digital value indicating the loop filter voltage and generates an analog voltage signal having the loop filter voltage indicated by the digital value. Further, the holdover circuit maintains the output clock signal at the constant frequency during a holdover of the phase-lock loop by regenerating the loop filter voltage based on the analog voltage signal. Because the analog voltage signal is based on the digital value, the voltage of the loop filter does not decay over time during the holdover of the phase-lock loop. As a result, the output clock signal remains at the constant frequency during the holdover of the phase-lock loop.
    Type: Grant
    Filed: August 19, 2009
    Date of Patent: September 13, 2011
    Assignee: Integrated Device Technology, Inc.
    Inventors: Pengfei Hu, Song Gao
  • Patent number: 8010935
    Abstract: An electronic design automation (EDA) tool for and method of optimizing a placement of process monitors (PMs) in an integrated circuit (IC). In one embodiment, the EDA tool includes: (1) a critical path/cell identifier configured to identify critical paths and critical cells in the IC, (2) a candidate PM position identifier coupled to the critical path/cell identifier and configured to identify a set of candidate positions for the PMs, (3) a cluster generator coupled to the critical path/cell identifier and configured to associate the critical cells to form clusters thereof and (4) a PM placement optimizer coupled to the candidate PM position identifier and the cluster generator and configured to place a PM within each of the clusters by selecting among the candidate positions.
    Type: Grant
    Filed: October 8, 2008
    Date of Patent: August 30, 2011
    Assignee: LSI Corporation
    Inventors: Alexander Tetelbaum, Sreejit Chakravarty
  • Patent number: 7939851
    Abstract: An electronic device with an amplifier output stage (OS) and an over-current detection means (OCDM) for detecting an output over-current (IHS, ILS) of the output stage (OS) is provided. The over-current detection means (OCDM) comprises a level detection means (LDM) for detecting a level of the output current (IO) exceeding a first level of the output current (IDET), and a timing detection means (TDM) for detecting a duration during which the output current (IO) exceeds the first current level (IDET) being a maximum current level.
    Type: Grant
    Filed: September 19, 2006
    Date of Patent: May 10, 2011
    Assignee: NXP B.V.
    Inventors: Paulus Petrus Franciscus Maria Bruin, Mike Hendrikus Splithof
  • Patent number: 7924061
    Abstract: A clock failure detection circuit comprises clock failure detection logic having a clock input providing an input clock signal, a counter and a reference clock input providing a reference clock signal to the counter for counting a number of reference clock cycles. The counter comprises a reset input arranged to receive successive reset pulses generated by at least one clock edge of the input clock signal to reset a counter value of the counter. The counter value before reset is used to identify a clock frequency error. A method of detecting a clock failure is also described. By using a counter value based on the reference clock cycles, and a reset trigger based on a clock edge of the input signal, it is possible to identify a clock frequency error in a much shorter time.
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: April 12, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Laurent Guillot, Kamel Abouda, Pierre Turpin
  • Publication number: 20110018586
    Abstract: To provide a signal judgement circuit that makes a judgement on signals received via at least four or more signal lines and enhances robustness and redundancy. A signal judgement circuit 1 making a judgement on a signal includes: an error signal generation circuit 10 receiving signals via at least four signal lines 100 and outputting an error signal when, of all the received signals, the number of signals taking on a same value does not exceed half of the number of the received signals; and an output selection circuit 30 selecting any one of the received signals and outputting the selected signal.
    Type: Application
    Filed: March 17, 2010
    Publication date: January 27, 2011
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Masataka KAZUNO, Kiminori NAKAJIMA
  • Publication number: 20100327913
    Abstract: There is provided a circuit and method for detecting a bad clock condition on a clock signal that includes sampling the value of the clock signal at a first plurality of time delays following a rising edge on the clock signal. This method also includes sampling the value of the clock signal at a second plurality of time delays following a falling edge on the clock signal.
    Type: Application
    Filed: June 24, 2010
    Publication date: December 30, 2010
    Applicant: STMicroelectronics Limited
    Inventor: Mark Trimmer
  • Patent number: 7859313
    Abstract: An edge-missing detector structure includes a first detector, a first delay unit, a first logic gate, a second detector, a second delay unit, and a second logic gate. After being input separately into the edge-missing detector structure, a first reference signal and a first clock signal are detected by the first and second detectors and then subjected to cycle suppression by the first and second logic gates, respectively, so as to generate a second reference signal and a second clock signal which present a phase difference less than 2?. Moreover, the edge-missing detector structure generates a compensative current corresponding to the number of occurrences of cycle suppression. Thus, a phase-locked loop (PLL) using the edge-missing detector structure can avoid cycle slip problems and achieve fast acquisition of phase lock.
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: December 28, 2010
    Assignee: National Chip Implementation Center National Applied Research Laboratories
    Inventors: Ting Hsu Chien, Chi Sheng Lin, Chin-Long Wey, Chun-Ming Huang, Ying-Zong Juang
  • Patent number: 7855580
    Abstract: A phase comparator includes an edge detecting unit to which a reference signal is input and to which a referred signal based on the reference signal is input as a feedback signal. The edge detecting unit detects an edge of the reference signal and an edge of the referred signal. The phase comparator also includes a phase-difference detecting unit that detects a phase difference between the edge of the reference signal and the edge of the referred signal. The phase comparator also includes a phase-difference-signal output unit that outputs a phase-difference signal for current control based on the phase difference. The phase comparator also includes an input-break detecting unit that detects an input break of the reference signal when an edge of the referred signal is again detected after an edge of the referred signal is detected and before an edge of the reference signal is detected.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: December 21, 2010
    Assignee: Fujitsu Limited
    Inventor: Ken Atsumi
  • Patent number: 7855581
    Abstract: Method for monitoring a real time clock and a device having real time clock monitoring capabilities, the device includes: (i) a real time clock tree, (ii) a clock frequency monitor that is adapted to determine a frequency of a real time clock signal, during a short monitoring period; (iii) a monitoring enable module, adapted to activate the clock frequency monitor during short motoring periods and to deactivate the clock frequency monitor during other periods, wherein the monitoring enable module is adapted to determine a timing of the short monitoring periods in a non-deterministic manner; and (iv) a real time clock violation indication generator adapted to indicate that a real time clock violation occurred, in response to an error signal provided from the clock frequency monitor.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: December 21, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Michael Priel, Asaf Ashkenazi, Dan Kuzmin
  • Publication number: 20100308868
    Abstract: The present invention relates to a clock supervision unit (100) and an electronic system clocked by at least one clock (c*) and using the clock supervision unit (100). The clock supervision unit (100) analyzes the at least one clock (c*) based on a monitor clock (m*) provided together with the at least one clock (c*) or separately to the clock supervision unit (100). The clock supervision unit (100) at least comprises an activity unit (210), a deviation unit (220) and an auxiliary clock generator (240). The auxiliary clock generator (240) outputs an auxiliary clock (a*). The activity unit (210) detects the presence of the monitor clock (m*) based on the auxiliary clock (a*) and the presence of the auxiliary clock (a*) based on the monitor clock (m*). The deviation unit (220) detects clock faults in the monitor clock (m*) based on the auxiliary clock (a*).
    Type: Application
    Filed: August 20, 2008
    Publication date: December 9, 2010
    Applicant: NXP B.V.
    Inventors: Manfred Zinke, Peter Fuhrmann, Markus Baumeister
  • Patent number: 7768318
    Abstract: A method and a circuit for detecting a disturbance of a state of at least one first flip-flop from a group of several first flip-flops of an electronic circuit, wherein: the respective outputs of the first flip-flops in the group are, independently from their functional purpose, combined to provide a signal and its inverse, triggering two second flip-flops having data inputs forced to a same state, the respective outputs of the second flip-flops being combined to provide the result of the detection; and a pulse signal comprising a pulse at least for each triggering edge of one of the first flip-flops in the group initializes the second flip-flops.
    Type: Grant
    Filed: May 16, 2008
    Date of Patent: August 3, 2010
    Assignee: STMicroelectronics (Rousset) SAS
    Inventors: Frédéric Bancel, David Hely, Nicolas Berard
  • Publication number: 20100171528
    Abstract: A clock failure detection circuit comprises clock failure detection logic having a clock input providing an input clock signal, a counter and a reference clock input providing a reference clock signal to the counter for counting a number of reference clock cycles. The counter comprises a reset input arranged to receive successive reset pulses generated by at least one clock edge of the input clock signal to reset a counter value of the counter. The counter value before reset is used to identify a clock frequency error. A method of detecting a clock failure is also described. By using a counter value based on the reference clock cycles, and a reset trigger based on a clock edge of the input signal, it is possible to identify a clock frequency error in a much shorter time.
    Type: Application
    Filed: March 27, 2006
    Publication date: July 8, 2010
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Laurent Guillot, Kamel Abouda, Pierre Turpin
  • Patent number: 7733131
    Abstract: A signal presence detection device has a first reference voltage generation device in the form of a first voltage divider, a second reference voltage generation device in the form of a second voltage divider and a third reference voltage generation device in the form of a third voltage divider. The detection device also has a signal conditioning device such as a hysteretic amplifier with an output that is coupled to the first and second voltage dividers. A comparison device is coupled to all three voltage dividers to compare a voltage of the first voltage divider to a voltage of the third voltage divider and to compare a voltage of the second voltage divider to the voltage of the third voltage divider. The comparison device is coupled at two outputs thereof to two respective inputs of an XOR device. The XOR device receives respective signals from the first and second outputs of the comparison device and produces a signal presence output that serves to indicate whether an incoming signal is present or absent.
    Type: Grant
    Filed: July 25, 2006
    Date of Patent: June 8, 2010
    Assignee: MRV Communications, Inc.
    Inventor: Zvi Regev
  • Patent number: 7734955
    Abstract: A method and system for improving Field Replacement Unit (FRU) isolation in memory sub-systems by monitoring Voltage Regulator Module (VRM) induced memory errors. A comparator compares the output voltage coming from the VRM to memory. If the comparator detects a VRM output voltage transient that is outside a rated threshold, then a counter is increased by one. If the counter exceeds a count threshold, a VRM error is posted. If a memory failure occurs within a predetermined period of time, then the VRM error pinpoints the VRM output voltage transient as being the likely cause of the memory failure.
    Type: Grant
    Filed: October 7, 2008
    Date of Patent: June 8, 2010
    Assignee: International Business Machines Corporation
    Inventors: Charles R. Dart, Edmund Sutherland Gamble, Gary Anthony Jansma, Terence Rodrigues, Robert Joseph Ruckriegel, Bruce James Wilkie
  • Patent number: 7714619
    Abstract: In order to provide a high frequency clock detection circuit capable to detect a high frequency clock using any period as a threshold, the high frequency clock detection circuit of the present invention includes a delay circuit having a delay time set to be longer than a clock period corresponding to the irregular high frequency state, a first flip-flop circuit for delay flip-flopping according to the clock signal and for being provided with the inverted and feedback inputted output from the first flip-flop circuit, a second flip-flop circuit for delay flip-flopping according to the clock signal and for being provided with the inverted and feedback inputted output from the second flip-flop circuit through the delay circuit, and a detection-result output circuit for detecting a difference between the output signal from the first flip-flop circuit and the output signal from the second flip-flop circuit and for providing the function circuit with the high frequency clock detection signal indicating the irregular
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: May 11, 2010
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Kenta Yamada
  • Patent number: 7710161
    Abstract: A digital circuit is disclosed for detecting clock activity in an integrated circuit (IC) device. In one implementation, a clock detection circuit can include two flip flops. A first flip flop detects activity on the clock being tested (e.g., the flip flop is set when a positive clock edge is detected). A second flip flop is coupled to the output of first flip flop and is operable by an enable signal to sample the output of the first flip flop. The output of the second flip flop is asserted as active, when a positive clock edge occurs between the release of the reset signal on the first flip flop and the assertion of the enable signal on the second flip flop. In some implementations, one or more additional flips can be interposed between the first and second flips to control metastability.
    Type: Grant
    Filed: January 13, 2009
    Date of Patent: May 4, 2010
    Assignee: ATMEL Corporation
    Inventor: Colin Bates
  • Patent number: 7705648
    Abstract: A circuit for monitoring a PWM signal and providing an output indicating a condition of the PWM signal. The circuit also uses condition based hysteresis to maintain an output value at a previous state until the condition of the PWM signal has remained unchanged for a given duration. In addition, the circuitry may be used in conjunction with a switching regulator to reduce switching noise during high duty cycle operation.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: April 27, 2010
    Assignee: National Semiconductor Corporation
    Inventor: Juan Paulo Fung
  • Publication number: 20100085082
    Abstract: One of a first signal, a second signal, and a third signal is received respectively from each of three inputs. A pattern formed by the first signal, the second signal, and the third signal is compared to a set of predetermined patterns. Based on the comparing, it is determined whether an error exists. If an error condition exists, a specific one of the inputs is identified as a cause of the error.
    Type: Application
    Filed: October 7, 2008
    Publication date: April 8, 2010
    Inventor: Kerfegar K. Katrak
  • Patent number: 7679404
    Abstract: A method to detect a missing a clock pulse is provided. The method begins by providing a clock signal and a delayed clock signal. The delayed clock signal is then sampled to generate a sample of the delayed clock signal. A missing clock pulse may be detected if the sample of the delayed clock signal does not equal an expected value of the delayed clock signal.
    Type: Grant
    Filed: June 23, 2006
    Date of Patent: March 16, 2010
    Assignee: Intel Corporation
    Inventor: Mark L. Neidengard
  • Publication number: 20100052730
    Abstract: Two latches store the state of a data signal at a transition of a clock signal. Comparison logic compares the outputs of the two latches and produces a signal to indicate whether the outputs are equal or unequal. Systems using the latches and comparison logic are described and claimed.
    Type: Application
    Filed: November 13, 2009
    Publication date: March 4, 2010
    Inventors: Edward Grochowski, Chris Wilkerson, Shih-Lien L. Lu, Murali Annavaram
  • Patent number: 7642842
    Abstract: A system and method is disclosed for providing communication of an over-current protection signal and current mode control signals between a controller chip and a power chip in an integrated circuit device that comprises a plurality of integrated circuit chips. The controller chip sends pulse width modulation signals and a reference current signal to the power chip. Current flow status detection circuitry in the power chip detects a current flow status in the power chip and provides a current flow status signal to the controller chip. The current flow status signal may comprise an over-current protection signal or current mode control signals. One advantageous embodiment of the invention comprises a switch mode power supply integrated circuit.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: January 5, 2010
    Assignee: National Semiconductor Corporation
    Inventors: Gregory J. Smith, Paul Ranucci, Glenn C. Dunlap, III, David Megaw
  • Patent number: 7622961
    Abstract: Two latches store the state of a data signal at a transition of a clock signal. Comparison logic compares the outputs of the two latches and produces a signal to indicate whether the outputs are equal or unequal. Systems using the latches and comparison logic are described and claimed.
    Type: Grant
    Filed: September 23, 2005
    Date of Patent: November 24, 2009
    Assignee: Intel Corporation
    Inventors: Edward Grochowski, Chris Wilkerson, Shih-Lien L. Lu, Murali Annavaram
  • Patent number: 7504865
    Abstract: A frequency sensor includes at least one a resistor element and a capacitor. A frequency is detected according to a charging/discharging time to/from the capacitor, thereby realizing a frequency sensor with reduced power consumption and reduced circuit scale. Further, plural resistors and plural capacitors can be provided, along with switches connected to the respective resistors and capacitors. Additionally, a time constant can be adjusted after production, whereby variations in production can be reduced. Furthermore, a self-diagnosis circuit can be included for determining whether the frequency sensor itself operates normally or not. Thus, a highly-reliable frequency sensor can be realized.
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: March 17, 2009
    Assignee: Panasonic Corporation
    Inventors: Rie Itoh, Eiichi Sadayuki
  • Patent number: 7498848
    Abstract: A clock monitor system for monitoring an input clock signal in an integrated circuit (IC) includes a clock failure detection circuit and a delay circuit. The clock failure detection circuit generates a control signal based on the input clock signal. The delay circuit is connected to the clock failure detection circuit and provides a clock status signal based on the control signal. The clock status signal indicates whether the input clock signal is operating correctly. The delay circuit provides the clock status signal to the IC after a predetermined number of input clock cycles.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: March 3, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Sanjay Kumar Wadhwa, Amit Kumar Srivastava
  • Patent number: 7496154
    Abstract: A hysteresis receiver containing two inverters and a logic controller. The inverters are implemented with threshold voltages equaling Vil and Vih, which together define the hysteresis window. The inverters receive the input signal and generate a respective inverted value. The logic controller propagates as output one of the two inverted values if the two inverted values are equal, and a prior value (corresponding to a previous sample) if the two inverted values are not equal. A receiver circuit with a hysteresis window defined by Vil and Vih, is obtained as a result.
    Type: Grant
    Filed: June 23, 2005
    Date of Patent: February 24, 2009
    Assignee: Texas Instruments Incorporated
    Inventor: Keshav Bhaktavatson Chintamani
  • Patent number: 7486114
    Abstract: A signal detector and method to detect the presence or absence of an incoming differential signal. The method nullifies the DC off-set of the signal detector so that it can detect a signal within a very narrow window. The common mode levels of the signal and reference paths are used for calibration which is done automatically by use of an embedded algorithm residing in a digital block. The calibration range and resolution are predetermined to cope with the technology, modeling, design methodology and human error.
    Type: Grant
    Filed: May 17, 2006
    Date of Patent: February 3, 2009
    Assignee: International Business Machines Corporation
    Inventors: Minhan Chen, Louis Hsu, Joseph Natonio, Karl D. Selander, Michael A. Sorna, Steven J. Zier
  • Patent number: 7482855
    Abstract: A fuse state detection circuit is comprised of a first fuse element, a second fuse element, and an output for carrying an output signal, the output signal represents a first logic state when the first fuse element is blown and the second fuse element is unblown and the output signal represents a second logic state when the first element is unblown and the second element is blown. The fuse state detection circuit produces an output signal whose state is recoverable from a negative triggering event and is capable of resolving itself to the correct state without the need for a reset pulse. Methods of using the fuse state detection circuit, such as a method of using fuse elements to control a setting within an electronic circuit, the improvement comprising using a pair of fuse elements to control a single setting, are also given.
    Type: Grant
    Filed: August 29, 2007
    Date of Patent: January 27, 2009
    Assignee: Micron Technology, Inc.
    Inventors: Christian N. Mohr, Scott E. Smith
  • Publication number: 20080303555
    Abstract: A tone detector is disclosed that is realizable in digital embodiment on a single integrated circuit die and does not require external components, such as a discrete capacitor. An input connects to a comparator, which in turn connects to one or more edge detectors and a flip flop. The edge detector outputs a pulse responsive to a detected edge. A counter is reset by the pulses from the edge detectors thereby preventing the counter from reaching a maximum value, which would otherwise be output from the counter and provided to a flip flop to clock in the comparator output at the D input to the flip flop. In operation, the comparator generates a rail to rail signal responsive to a received tone, which in turn is clocked through the flip flop as a logic high output indicating presence of a tone.
    Type: Application
    Filed: June 5, 2007
    Publication date: December 11, 2008
    Inventor: Amit Burstein
  • Patent number: 7461303
    Abstract: A system for improving Field Replacement Unit (FRU) isolation in memory sub-systems by monitoring Voltage Regulator Module (VRM) induced memory errors. A comparator compares the output voltage coming from the VRM to memory. If the comparator detects a VRM output voltage transient that is outside a rated threshold, then a counter is increased by one. If the counter exceeds a count threshold, a VRM error is posted. If a memory failure occurs within a predetermined period of time, then the VRM error pinpoints the VRM output voltage transient as being the likely cause of the memory failure.
    Type: Grant
    Filed: March 23, 2007
    Date of Patent: December 2, 2008
    Assignee: International Business Machines Corporation
    Inventors: Charles R. Dart, Edmund Sutherland Gamble, Gary Anthony Jansma, Terence Rodrigues, Robert Joseph Ruckriegel, Bruce James Wilkie
  • Publication number: 20080272808
    Abstract: A phase/frequency locked loop (PLL) includes circuitry adapted to detect missing pulses of a reference clock and to control the phase bump of the PLL. The circuitry includes, in part, first and second flip-flops, as well as a one-shot block. The first flip-flop has a data input terminal responsive to a voltage supply, and a clock terminal responsive to an inverse of feedback clock. The second flip-flop has a data input terminal responsive to an output of the first flip-flop, and a clock terminal responsive to the inverse of the feedback clock. The one-shot block generates a pulse in response to a rising edge of the reference clock that is used to generate the feedback clock. The one-shot block generates an output signal applied to a reset terminal of the first flip-flop.
    Type: Application
    Filed: May 4, 2007
    Publication date: November 6, 2008
    Applicant: Exar Corporation
    Inventor: James Toner Sundby
  • Publication number: 20080238488
    Abstract: Methods and apparatus for power monitoring with sequencing and supervision are disclosed. An example method disclosed herein comprises supervising a first power rail and a second power rail, sequencing a first enable signal associated with the first power rail and a second enable signal associated with the second power rail, and determining whether the first power rail is enabled based on regulation information determined while supervising the first power rail.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 2, 2008
    Inventors: David Allan Comisky, Brandon Christopher Azbell, Bradley James Griffis
  • Patent number: 7414438
    Abstract: The clock based voltage deviation detector of the present invention includes a pulse module, an indicator module and a correlation module. The pulse module generates a stream of reset pulses as a function of a clock signal. The indicator module generates a pass/fail indicator signal as a function of the reset pulse stream and a difference between an input signal and a reference voltage. The correlation module correlates an event (e.g., overvoltage or undervoltage) of the pass/fail indicator signal with a period of the clock signal at which the event occurred.
    Type: Grant
    Filed: March 17, 2004
    Date of Patent: August 19, 2008
    Assignee: Credence Systems Corporation
    Inventors: Thomas Nulsen, Jose Rosado, Robert Glenn
  • Patent number: 7391240
    Abstract: A clock anomaly detection circuit includes: a dividing unit configured to output a divided target clock by dividing frequency of a target clock; a first time width measurement unit configured to obtain values of the divided target clock using rising edges of a monitoring clock that is synchronized with the target clock, and to measure an H level time with and an L level time width; a second time width measurement unit configured to obtain values of the divided target clock using falling edges of the monitoring clock, and to measure an H level time with and an L level time width; and an anomaly determination unit configured to determine that the target clock is abnormal when an anomaly is detected in the H level time width or the L level time width measured in the first time width measurement unit and when an anomaly is detected in the H level time width or the L level time width measured in the second time width measurement unit.
    Type: Grant
    Filed: August 14, 2006
    Date of Patent: June 24, 2008
    Assignee: Fujitsu Limited
    Inventor: Shosaku Yamasaki
  • Publication number: 20080079463
    Abstract: A clock monitor system for monitoring an input clock signal in an integrated circuit (IC) includes a clock failure detection circuit and a delay circuit. The clock failure detection circuit generates a control signal based on the input clock signal. The delay circuit is connected to the clock failure detection circuit and provides a clock status signal based on the control signal. The clock status signal indicates whether the input clock signal is operating correctly. The delay circuit provides the clock status signal to the IC after a predetermined number of input clock cycles.
    Type: Application
    Filed: September 6, 2007
    Publication date: April 3, 2008
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Sanjay Kumar WADHWA, Amit Kumar SRIVASTAVA
  • Patent number: 7353412
    Abstract: The number of electrical devices implemented in motor vehicles and supplied with electricity by the motor vehicle battery rises with each generation. The manufacturers of motor vehicles make great demands on electrical device to be built-in their motor vehicles, especially to the stand-by power consumption of the built-in devices in order to protect the motor vehicle battery from a fast and undesired unloading during the stop of the motor vehicle. The present invention relates to an electrical circuit provided to be implemented in motor vehicle built-in devices for limiting the power consumption during the stand-by thereof, i.e. to reduce the power consumption to almost no consumption. Further, the present invention relates to an electrical motor vehicle built-in device having the aforementioned electrical circuit for limiting the power consumption of the electrical motor vehicle built-in device.
    Type: Grant
    Filed: June 27, 2002
    Date of Patent: April 1, 2008
    Assignee: Nokia Corporation
    Inventor: Jochen Spilker
  • Publication number: 20080024173
    Abstract: A malfunction detection circuit realized by a simple circuit structure is incorporated into a semiconductor integrated circuit without increasing the scale thereof, in order to prevent loss etc. of data due to a malfunction of the semiconductor integrated circuit. Malfunctions can be prevented without relying on measuring temperature or power supply voltage which are analog values, thereby improving the reliability of the semiconductor integrated circuit. A detection-target flip-flop in a function block is synchronized to a clock, and another flip-flop is synchronized to a clock whose phase has been delayed behind or advanced ahead of the former clock. A logic operation is performed using output from both flip-flops to determine whether a latch operation has been performed at an appropriate clock pulse edge in a clock pulse train. The malfunction countermeasure is performed if the latch operation is determined to have been performed at an inappropriate clock pulse edge.
    Type: Application
    Filed: July 25, 2007
    Publication date: January 31, 2008
    Inventors: Masaaki Nagai, Kenji Tutumi, Hideshi Nakazawa
  • Patent number: 7297922
    Abstract: An apparatus for optical receiver circuit protection includes a bias source, a bias monitor, and a comparator. The bias source is to provide a bias voltage to an optical receiver. The bias monitor is coupled to measure a current through the optical receiver, where the current changes responsive to received optical energy. A comparator is coupled to the bias monitor, where the comparator has a first state if the current is less than a threshold current level and where the comparator has a second state if the current is greater than the threshold current level. The bias source is coupled to be enabled responsive to the comparator switching to the first state and disabled responsive to the comparator switching to the second state.
    Type: Grant
    Filed: September 28, 2005
    Date of Patent: November 20, 2007
    Assignee: Intel Corporation
    Inventors: Thomas J. Giovannini, Craig Schulz, Song Q. Shang
  • Patent number: 7296170
    Abstract: A microcontroller integrated circuit with a clock controller and a processor automatically switches the source of the clock signal that clocks the processor from a failed fast external precision oscillator to a slow internal backup oscillator, then enables a fast internal precision oscillator, and finally switches to the fast internal precision oscillator. A failure detection circuit within the clock controller detects a failure of the external precision oscillator and sends an associated interrupt signal to the processor. The clock controller decouples the external oscillator from the processor and couples the backup oscillator to the processor. The microcontroller integrated circuit then enables the fast internal precision oscillator, decouples the backup oscillator, and couples the fast internal precision oscillator to the processor.
    Type: Grant
    Filed: January 23, 2004
    Date of Patent: November 13, 2007
    Assignee: Zilog, Inc.
    Inventors: Melany Ann Richmond, Robert Walter Metzler, Jr.
  • Patent number: 7276955
    Abstract: A fuse state detection circuit is comprised of a first fuse element, a second fuse element, and an output for carrying an output signal, the output signal represents a first logic state when the first fuse element is blown and the second fuse element is unblown and the output signal represents a second logic state when the first element is unblown and the second element is blown. The fuse state detection circuit produces an output signal whose state is recoverable from a negative triggering event and is capable of resolving itself to the correct state without the need for a reset pulse. Methods of using the fuse state detection circuit, such as a method of using fuse elements to control a setting within an electronic circuit, the improvement comprising using a pair of fuse elements to control a single setting, are also given.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: October 2, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Christian N. Mohr, Scott E. Smith
  • Patent number: 7265590
    Abstract: A semiconductor apparatus for flexibly and effectively configuring a delay monitor circuit without an increase in circuit scale includes a delay signal generation circuit for switching the configuration of delay element arrays based on first configuration information and second configuration information and propagating a delay element array wherein a pulse is switched, a register group having a first register for the first configuration information and a second register for second configuration information, a selector for outputting to the delay signal generation circuit the first configuration information and second configuration information in accordance with an instruction of a selection signal in a time sharing way, and a control circuit for controlling a power source voltage based on delay information of a delay element array and outputting to the selector a selection signal to select from the first configuration information and second configuration information in a time sharing way.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: September 4, 2007
    Assignee: Sony Corporation
    Inventors: Takahiro Seki, Masakatsu Nakai, Tetsumasa Meguro
  • Patent number: 7257323
    Abstract: This invention offers a signal-off detection circuit allowing arbitrary setting of an issuing time (response time) of a signal disconnection alarm without being affected by a time constant of a direct current feedback circuit giving an offset voltage to an amplifier for amplifying a data signal. Input data signals per a fixed time determined by a timer is counted by a counter, and a count value is compared with a predetermined set value in a comparator. A configuration is made such that a signal disconnection alarm may be issued by detecting a disconnection state of the data signal according to a comparison result. Thereby, an issuing time of a signal disconnection alarm can be set without being affected by a time constant of a direct current feedback circuit giving an offset voltage to an amplifier for amplifying a data signal of a preceding stage.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: August 14, 2007
    Assignee: NEC Corporation
    Inventors: Hidemi Noguchi, Tetuo Tateyama, Madoka Kimura
  • Patent number: 7215210
    Abstract: A clock signal outputting method in which either a clock signal based on a signal from the outside or an alternative clock signal from a fixed oscillator is selected and outputted, wherein, when the clock signal is selected to be outputted, the fixed oscillator is put into non-operating state, and when any error occurs in the clock signal, the fixed oscillator is operated to output the alternative clock signal.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: May 8, 2007
    Assignee: Seiko Epson Corporation
    Inventor: Hiroyuki Ogiso
  • Patent number: 7200186
    Abstract: Methods and apparatus are disclosed for using in-band signal(s) over a differential serial data link to reduce power usage of a transmitter and receiver coupled by the link.
    Type: Grant
    Filed: March 14, 2002
    Date of Patent: April 3, 2007
    Assignee: Intel Corporation
    Inventor: Zale T. Schoenborn
  • Patent number: 7183831
    Abstract: A clock switching circuit suitably adapted to stable switching operation of high-frequency multiphase clock signals. The clock switching circuit receives two clock signals and selectively outputs one of the two clock signals in accordance with a selection signal. The clock switching circuit includes a switching controller that transfers the selection signal at the beginning of a period in which both of the two clock signals are active, and an internal selector that selectively outputs one of the two clock signals in response to the selection signal transferred from the switching controller.
    Type: Grant
    Filed: October 27, 2004
    Date of Patent: February 27, 2007
    Assignee: Fujitsu Limited
    Inventor: Akimitsu Ikeda
  • Patent number: 7173495
    Abstract: A redundant-source clock generator has only two oscillators, rather than three oscillators. A secondary oscillator is phase-locked to a primary clock from a primary oscillator using a phase detector, charge pump, and filter that generate a control voltage to the secondary oscillator that determine the frequency of a secondary clock. The primary clock is compared to the secondary clock to detect primary clock failure. When clock failure is detected, a mux is switched to select a delayed secondary clock rather than a delayed primary clock to output as a system clock. Since the mux receives delayed clock signals, clock-failure detection has additional time to detect the clock failure before the clock failure is propagated through the mux. When the primary oscillator fails and the clock failure is detected, the phase detector stops comparing a feedback secondary clock to the primary clock and instead holds the control voltage steady.
    Type: Grant
    Filed: April 5, 2005
    Date of Patent: February 6, 2007
    Assignee: Pericom Semiconductor Corp
    Inventors: David J. Kenny, Kyusun Choi
  • Patent number: 7170949
    Abstract: Methods and apparatus are disclosed for transitioning a receiver from a first state to a second state using an in-band signal over a differential serial data link.
    Type: Grant
    Filed: March 14, 2002
    Date of Patent: January 30, 2007
    Assignee: Intel Corporation
    Inventor: Zale T. Schoenborn
  • Patent number: 7113003
    Abstract: According to some embodiments, a presence indication associated with an attachment is provided.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: September 26, 2006
    Assignee: Intel Corporation
    Inventor: Knut S. Grimsrud
  • Patent number: 7106116
    Abstract: A pulse duty deterioration detection circuit with a high monitoring precision is easily provided. The pulse duty deterioration detection circuit comprises a delay circuit comprised of a general-purpose gate circuit which generates a delayed synchronous to-be-monitored clock by delaying the to-be-monitored clock by a predetermined time, a latch circuit which detects based on the to-be-monitored clock and the delayed synchronous to-be-monitored clock that a value of a decrease in a pulse width to be determined by a pulse duty of the to-be-monitored clock becomes smaller than the predetermined time, and a flip-flop circuit which samples an output signal of the latch circuit based on the to-be-monitored clock.
    Type: Grant
    Filed: October 21, 2003
    Date of Patent: September 12, 2006
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Toshimi Yamada