For Adjusting The Frequency Or Beat Patents (Class 368/200)
  • Patent number: 11372374
    Abstract: A timepiece movement includes a stepping motor having a rotor for rotating an indicating hand, and a control unit for rotating the rotor by using a main drive pulse and an auxiliary drive pulse. When the indicating hand is rotated using a detection drive pulse based on the main drive pulse, the control unit determines a reference position of the indicating hand by detecting a rotation state of the rotor.
    Type: Grant
    Filed: October 18, 2018
    Date of Patent: June 28, 2022
    Assignee: SEIKO INSTRUMENTS INC.
    Inventor: Kenji Ogasawara
  • Patent number: 10429206
    Abstract: A counting device and a pedometer device is described. The counting device includes: a piezoelectric sensor generating a voltage signal when pressed; a rectifier receiving the voltage signal and rectifying the voltage signal to produce a trigger signal; a non-volatile counter receiving the trigger signal, and including a plurality of non-volatile D flip-flops counting according to the trigger signal and storing count data; a processing module reading the count data and using the count data to generate a counting value; and a wireless communication module transmitting the counting value to an external device. The counting device is powered with electrical energy of the voltage signal generated by the piezoelectric sensor.
    Type: Grant
    Filed: August 8, 2017
    Date of Patent: October 1, 2019
    Assignee: NUVOTON TECHNOLOGY CORPORATION
    Inventors: Hsi-Jung Tsai, Cheng-Chih Wang, Chih-Wei Tsai
  • Patent number: 10394273
    Abstract: A circuit device includes an oscillation circuit, a clock signal output circuit that outputs a clock signal based on an output signal from the oscillation circuit, and an output control circuit. The output control circuit includes a counter circuit that performs a counting process on the basis of the output signal from the oscillation circuit, and a count enable signal generation circuit that outputs a count enable signal for the counter circuit. The counter circuit starts the counting process when the count enable signal becomes active, and outputs an output enable signal for the clock signal to the clock signal output circuit on the basis of a result of the counting process.
    Type: Grant
    Filed: October 5, 2017
    Date of Patent: August 27, 2019
    Assignee: Seiko Epson Corporation
    Inventor: Takehiro Yamamoto
  • Patent number: 8721170
    Abstract: A rotation detection unit configured to detect the condition of rotation of a stepping motor on the basis of an induced signal generated in a drive coil of the stepping motor in a detection period in which the condition of rotation of the stepping motor is detected and a control unit configured to rotationally drive the stepping motor by supplying a drive signal to the drive coil of the stepping motor within the driving period in which the stepping motor is rotationally driven are provided. The driving period and part of the detection period are configured to overlap with each other in a first time interval, and the control unit stops supply of the drive signal to the drive coil of the stepping motor in the first time interval.
    Type: Grant
    Filed: December 13, 2012
    Date of Patent: May 13, 2014
    Assignee: Seiko Instruments Inc.
    Inventors: Saburo Manaka, Kenji Ogasawara, Kazumi Sakumoto, Keishi Honmura, Kosuke Yamamoto
  • Patent number: 8610381
    Abstract: A voltage determination device includes a reference voltage generation circuit; a determination target voltage line; a first voltage line; a second voltage line; and a switching circuit disposed between the first voltage line and the second voltage line. The switching circuit is provided for performing a switching operation according to a level of the determination target voltage. The voltage determination device includes a determining circuit for determining the level of the determination target voltage, and a control unit is provided for controlling a level of an electric current flowing between the first voltage line and the second voltage line. The control unit controls a resistivity between the switching circuit and the second voltage line so that the level of the electric current is maintained at a specific level when the determining circuit determines the level of the determination target voltage.
    Type: Grant
    Filed: January 11, 2012
    Date of Patent: December 17, 2013
    Assignee: Lapis Semiconductor Co., Ltd.
    Inventor: Kikuo Utsuno
  • Publication number: 20130308430
    Abstract: Method of adjusting the oscillation frequency of a timepiece regulating assembly with no index assembly, formed of a balance and balance spring assembly, to a predetermined oscillation frequency: a particular balance spring assembly is randomly taken from a production of toleranced products; the return torque of said balance spring assembly is measured; a balance is randomly taken from a production of toleranced products; a calculation is made of the theoretical inertia (IT) of said particular balance required to achieve said predetermined oscillation frequency, according to said measured return torque of said balance spring; the real inertia (IR) of said particular balance is measured; by direct action on said particular balance, the inertia of said particular balance is corrected to said calculated theoretical inertia value (IT) in order to obtain said predetermined oscillation frequency for said regulating assembly formed by said particular balance, and by said particular balance spring assembly.
    Type: Application
    Filed: November 17, 2011
    Publication date: November 21, 2013
    Applicant: Nivarox-Far S.A.
    Inventors: Marco Verardo, Philippe Barthoulot
  • Patent number: 8550700
    Abstract: A clock movement is provided that contains a constant force device. In accordance with one implementation, the clock movement includes a spiral spring, and a train, having a first kinematic chain arranged to connect a main energy source to a first end of the spiral spring and a second kinematic chain for connecting a time base to a second end of the spiral spring. One of the first and second kinematic chains may contain an adjustment mobile comprising first and second members connected to each other by a friction such that a rotation of one member drives the other member during routine working of the clock movement. One of these members may include an adjustment member having at least one bearing surface arranged such that it is possible to act upon the latter so as to rotate the adjustment member without rotating the other member by dint of friction, in order to adjust the load state of the spiral spring.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: October 8, 2013
    Assignee: Agenhor S.A.
    Inventor: Jean-Marc Wiederrecht
  • Publication number: 20130170328
    Abstract: A rotation detection unit configured to detect the condition of rotation of a stepping motor on the basis of an induced signal generated in a drive coil of the stepping motor in a detection period in which the condition of rotation of the stepping motor is detected and a control unit configured to rotationally drive the stepping motor by supplying a drive signal to the drive coil of the stepping motor within the driving period in which the stepping motor is rotationally driven are provided. The driving period and part of the detection period are configured to overlap with each other in a first time interval, and the control unit stops supply of the drive signal to the drive coil of the stepping motor in the first time interval.
    Type: Application
    Filed: December 13, 2012
    Publication date: July 4, 2013
    Applicant: SEIKO INSTRUMENTS INC.
    Inventor: SEIKO INSTRUMENTS INC.
  • Publication number: 20130107677
    Abstract: The autoregulating circuit regulates the oscillation frequency of an oscillating mechanical system, such as a balance having a balance spring. A piezoelectric element is mounted on the oscillating balance spring to generate an alternating voltage and connected to the autoregulating circuit, which rectifies the alternating voltage and regulates the alternating voltage frequency. The rectified voltage is stored in a capacitor to power the autoregulating circuit. The autoregulating circuit includes an oscillator stage connected to a MEMS resonator for supplying a reference signal, a means for comparing the frequency of the alternating voltage to the reference signal frequency, and a frequency adaptation unit for supplying a frequency adaptation signal to the piezoelectric element according to the result from the comparison means, to regulate the oscillation frequency of the balance. The electronic components of the autoregulating circuit form a single electronic module.
    Type: Application
    Filed: October 23, 2012
    Publication date: May 2, 2013
    Applicant: The Swatch Group Research and Development Ltd.
    Inventor: The Swatch Group Research and Development Ltd
  • Patent number: 8392001
    Abstract: A method and apparatus for externally aided self adjusting real time clock have been disclosed. A circuit having a pulse train output is coupled to an adjusting circuit, a real-time clock is coupled to the adjusting circuit, and a proportional integral derivative time processor is coupled to the adjusting circuit, and where the adjusting circuit affects the pulse train output.
    Type: Grant
    Filed: May 3, 2008
    Date of Patent: March 5, 2013
    Assignee: Integrated Device Technology, Inc.
    Inventors: Tacettin Isik, Jan Gazda
  • Publication number: 20130051184
    Abstract: An integrated circuit (IC), a method of operating the IC and devices incorporating the IC. In one embodiment, the IC includes: (1) a monolithic substrate and (2) a time code receiver supported by the monolithic substrate and configured to receive a timing signal and employ the timing signal to adjust a local oscillator of a real time clock (RTC).
    Type: Application
    Filed: November 16, 2011
    Publication date: February 28, 2013
    Inventors: Oren Eliezer, Thomas Jung, Steve Morrison, Mary Cooley
  • Patent number: 8344814
    Abstract: A circuit comprises a frequency divider configured to receive an oscillating signal generated by an oscillator and to divide the oscillating signal into a clock signal, wherein the division ratio of the frequency divider is set to a value equal to one of: the integer part of the resonant frequency of the oscillator and the integer part of the resonant frequency of the oscillator plus 1. The circuit further comprises a control element which switchable connects or disconnects a calibration element to alter the frequency of the oscillation signal input to the frequency divider based on a number of oscillations that have transpired in the oscillating signal.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: January 1, 2013
    Assignee: STMicroelectronics (Shenzhen) R&D Co. Ltd.
    Inventor: Henry Ge
  • Patent number: 8251575
    Abstract: An electronic timepiece includes a limiting circuit that is controlled by the rotation detecting circuit and limits output of a locking pulse PL. The electronic timepiece prevents the display of the incorrect current time due to impact, by executing impact detection when rotation is detected, and prevents errant hand operation in a magnetic field by not outputting a locking pulse PL by prohibiting impact detection when non-rotation is detected. The electronic timepiece controls the limiting circuit using a ranking-down storing circuit and if the electronic timepiece employs multi-stage load correction, executes impact detection when regularly occurring non-rotation is detected. Thereby, errant deviation in the display of the current time due to impact is prevented. The electronic timepiece prohibits the impact detection and causes the locking pulse PL not to be output when non-rotation other than those occurring regularly is detected. Thereby, errant hand operation in a magnetic field is prevented.
    Type: Grant
    Filed: March 6, 2009
    Date of Patent: August 28, 2012
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Koichi Sato, Takuji Ike, Takayuki Uchida
  • Publication number: 20120163134
    Abstract: Systems and methods for operating with oscillators configured to produce an oscillating signal having an arbitrary frequency are described. The frequency of the oscillating signal may be shifted to remove its arbitrary nature by application of multiple tuning signals or values to the oscillator. Alternatively, the arbitrary frequency may be accommodated by adjusting operation one or more components of a circuit receiving the oscillating signal.
    Type: Application
    Filed: March 2, 2012
    Publication date: June 28, 2012
    Applicant: Sand9, Inc.
    Inventors: Klaus Juergen Schoepf, Reimund Rebel, Jan H. Kuypers
  • Publication number: 20110235474
    Abstract: A clock movement is provided that contains a constant force device. In accordance with one implementation, the clock movement includes a spiral spring, and a train, having a first kinematic chain arranged to connect a main energy source to a first end of the spiral spring and a second kinematic chain for connecting a time base to a second end of the spiral spring. One of the first and second kinematic chains may contain an adjustment mobile comprising first and second members connected to each other by a friction such that a rotation of one member drives the other member during routine working of the clock movement. One of these members may include an adjustment member having at least one bearing surface arranged such that it is possible to act upon the latter so as to rotate the adjustment member without rotating the other member by dint of friction, in order to adjust the load state of the spiral spring.
    Type: Application
    Filed: July 30, 2009
    Publication date: September 29, 2011
    Inventor: Jean-Marc Wiederrecht
  • Publication number: 20110013494
    Abstract: An electronic timepiece includes a limiting circuit that is controlled by the rotation detecting circuit and limits output of a locking pulse PL. The electronic timepiece prevents the display of the incorrect current time due to impact, by executing impact detection when rotation is detected, and prevents errant hand operation in a magnetic field by not outputting a locking pulse PL by prohibiting impact detection when non-rotation is detected. The electronic timepiece controls the limiting circuit using a ranking-down storing circuit and if the electronic timepiece employs multi-stage load correction, executes impact detection when regularly occurring non-rotation is detected. Thereby, errant deviation in the display of the current time due to impact is prevented. The electronic timepiece prohibits the impact detection and causes the locking pulse PL not to be output when non-rotation other than those occurring regularly is detected. Thereby, errant hand operation in a magnetic field is prevented.
    Type: Application
    Filed: March 6, 2009
    Publication date: January 20, 2011
    Inventors: Koichi Sato, Takuji Ike, Takayuki Uchida
  • Patent number: 7854544
    Abstract: A clock device is provided for generating a real-time clock. The clock device includes a frequency generator, a measuring module, a setting module and a timing module. The frequency generator generates a frequency signal. The measuring module is coupled to the frequency generator for measuring the frequency signal and generating a measuring frequency value. The setting module is coupled to the measuring module for generating an error setting value corresponding to the measuring frequency value. The timing module is coupled to the frequency generator and the setting module for compensating the frequency signal according to the error setting value and generating the real-time clock.
    Type: Grant
    Filed: September 10, 2007
    Date of Patent: December 21, 2010
    Assignee: Princeton Technology Corporation
    Inventors: Chun-Ming Cheng, Chia-Bo Lin
  • Publication number: 20090257321
    Abstract: A method for correcting time error in an oscillator operated clock according to one aspect of the invention includes at selected times determining at least one of a time error in the clock and a frequency difference between the oscillator and a reference oscillator by detecting a time reference signal. A change in the at least one of the time error and the frequency difference between a first one and a second one of the detecting the time reference signals is determined. A frequency of the oscillator is adjusted so as to substantially cancel a cumulative time error between the second one of the detecting the time reference signal and a selected detecting the time reference signal.
    Type: Application
    Filed: April 14, 2008
    Publication date: October 15, 2009
    Inventors: Gary Lee Scott, Joseph Ernest Dryer
  • Publication number: 20090168610
    Abstract: The horological movement comprises a regulating device having an oscillation frequency f and an escapement (11, 12) for maintaining the oscillations of the regulating device. The escapement comprises an escape wheel (11) having N teeth. The frequency f is at least equal to about 5 Hz, and the ratio between the number N of teeth and the frequency f is substantially equal to 5.
    Type: Application
    Filed: December 22, 2008
    Publication date: July 2, 2009
    Inventors: Christophe GIGANDET, Francisco Dias, Armin Behrend
  • Patent number: 7455447
    Abstract: A method for a portable device is disclosed. A reference clock is provided. A first time value and a first index are recording at a first time point. A second index is recorded at a second time point. The first time point and the second time point are counted according to the reference clock. The first index and the second index are calculated. A second time value is set according to the calculating result.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: November 25, 2008
    Assignee: Mediatek Inc.
    Inventor: Tzi-Yu Jau
  • Publication number: 20070268787
    Abstract: A method for a portable device is disclosed. A reference clock is provided. A first time value and a first index are recording at a first time point. A second index is recorded at a second time point. The first time point and the second time point are counted according to the reference clock. The first index and the second index are calculated. A second time value is set according to the calculating result.
    Type: Application
    Filed: September 29, 2006
    Publication date: November 22, 2007
    Applicant: MEDIATEK INC.
    Inventor: Tzi-Yu Jau
  • Patent number: 7118269
    Abstract: A method of correcting a real-time clock of an electronic apparatus, notably a mobile telephone, in which the real-time clock operates with a first clock generator which generates a real-time clock while the electronic apparatus operates with a second clock generator which generates a system clock, which method includes the following steps: determining the actual frequency of the real-time clock, determining the ratio Vclock/standard of the actual frequency of the real-time clock to the reference frequency of a standard clock, determining the deviation time of the real-time clock per second from the difference (1?Vclock/standard), determining, on the basis of the deviation time per second, a time difference dt within which the real-time clock is to be corrected by a correction time difference ?t, correcting the real time by ?t after expiration of dt.
    Type: Grant
    Filed: March 13, 2002
    Date of Patent: October 10, 2006
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Andreas Bening
  • Patent number: 6956793
    Abstract: A frequency divider circuit uses a base counter to frequency divide a clock signal with period T by an integer value N and employs a cyclic rotational select circuit to select among multiple equally phase shifted signals of a multiple phase clock to generate a fractional term P/k where P is variable from 0 to k?1. The counter counts an output clock that corresponds to the output of a multiplexer selecting from among the multiple clock phases. Depending on the desired fractional term, after N counts of the output clock phases of the multiple phase clock are selected glitch free by rotationally selecting a first phase, and skipping either 0, 1, 2 . . . up to k?1 sequential phases to generate fractional terms 0, 1/k, 2/k, 3/k . . . k?1/k, respectively, thus providing frequency division corresponding to N+P/k where P may be varied from 0 to k?1.
    Type: Grant
    Filed: November 20, 2003
    Date of Patent: October 18, 2005
    Assignee: International Business Machines Corporation
    Inventor: Hung C. Ngo
  • Publication number: 20030174587
    Abstract: A method of correcting a real-time clock of an electronic apparatus, notably a mobile telephone, in which the real-time clock operates with a first clock generator which generates a real-time clock while the electronic apparatus operates with a second clock generator which generates a system clock, which method includes the following steps:
    Type: Application
    Filed: November 12, 2002
    Publication date: September 18, 2003
    Inventor: Andreas Bening
  • Patent number: 6616328
    Abstract: Accuracy adjustment apparatus for a timepiece has an accuracy adjustment data input control section including a case-mounted switch such as a crown of the timepiece. A crown state detection signal is used to determine the state of the crown. When an accuracy adjustment data input mode is indicated based on the position of the crown, an indicator of the timepiece is driven to provide a visual indication of accuracy adjustment data selectable by operation of the crown. When the proper accuracy adjustment data has been selected, the data is stored to a memory.
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: September 9, 2003
    Assignee: Seiko Instruments Inc.
    Inventor: Hiroyuki Masaki
  • Publication number: 20020141290
    Abstract: A data transmission/reception system for wrist-type electronic timepiece. The data transmission/reception system for electronic timepieces comprises a data transmission device for generating data signals, and an electronic timepiece that receives data signals from the data transmission device by utilizing a coil for driving the hands, wherein the electronic timepiece is provided with a timing signal-generating means which generates a timing signal, and the data transmission device is provided with a timing signal-receiving means which receives the timing signals output from said hand-driving coil and transmits data signals in synchronism with the timing signals that are received. The data are transmitted and received in an ordinary hand-moving state without halting the timepiece while the functions are being operated. Therefore, there is no need of adjusting the time after the operation of the functions.
    Type: Application
    Filed: May 29, 2002
    Publication date: October 3, 2002
    Applicant: CITIZEN WATCH CO., LTD.
    Inventor: Masao Sakuyama
  • Patent number: 6449217
    Abstract: A time display is comprised of a low cost low accuracy RC oscillator. A series of pulses derived from this oscillator, for example, with a period of 1 second, is used for controlling a diode. An accurate time-display function of a car radio is also derived from this oscillator. This is possible as the main micro-controller periodically calibrates the low accuracy oscillator using a high accuracy crystal clock. Specifically, it measures the PC oscillator period in order to correct, in the micro-controller, the time issued from the RC oscillator.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: September 10, 2002
    Assignee: Siemens AG
    Inventors: Pascal Hayet, Alain Sauve
  • Patent number: 6304517
    Abstract: A real time clock, suitable for use in mobile units in a radiocommunication system, is calibrated during production, and corrects for timing inaccuracies during normal operation. As a result, the accuracy of the real time clock's crystal oscillator is increased economically and efficiently. Frequency error correction is performed by periodically adjusting the frequency of the real time clock by a fixed amount once for every interval of time defined by an adjustment value. The adjustment value is determined by a calibration procedure performed during manufacture of the mobile unit.
    Type: Grant
    Filed: June 18, 1999
    Date of Patent: October 16, 2001
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Rolf Erik Ledfelt, Anders Wilhelm Östsjö
  • Patent number: 5881022
    Abstract: A device (10) for automatically adjusting a device containing a clock (70) that derives its timing function from the frequency of an alternating current signal on a power line is provided. The device (10) includes a controller (15) that receives user-entered controls for adjusting the clock (70) and generates control signals in response to the user-entered controls. The device also includes a frequency changer (11) that responds to the control signals to increase or decrease the frequency of the alternating current signal applied to the clock (70) so that the clock (70) may be adjusted.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: March 9, 1999
    Assignee: Illinois Information Technology Corporation
    Inventor: Sanford J. Morganstein
  • Patent number: 5825172
    Abstract: A rotating transmission line for use in spectrum up-scaling or down-scaling of signals. The rotating medium is characterized by different velocity gradients, whereby when a signal propagates in such medium, the signal undergoes a Doppler effect as it propagates through the moving medium.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: October 20, 1998
    Inventor: Gopalkrishna G. Nadkarni
  • Patent number: 5740129
    Abstract: A real time clock is arranged to generate output signals indicative of time of day. An oscillating device (101) produces a first clocking signal which is adjusted in response to a calibration value to produce an output clocking signal. A processor (102) re-calculates the calibration value in response to external clocking signals received from a cellular base station for mobile telephones. The clock may be provided within a mobile telephone and the oscillating device may also be used to provide sleep clock signals allowing a high frequency system clock to be de-activated for periods while the telephone is in a stand-by condition.
    Type: Grant
    Filed: February 6, 1996
    Date of Patent: April 14, 1998
    Assignee: Nokia Mobile Phones Limited
    Inventor: Simon Frampton
  • Patent number: 5717661
    Abstract: A method and apparatus for adjusting the accuracy of an electronic timepiece that includes an oscillator with a 2.sup.n frequency output, means for reducing the oscillator output frequency to a time keeping frequency, means for counting the time keeping frequency, and means for displaying the time corresponding to the count of the time keeping frequency. The timepiece is initially synchronized with a time standard. After a period of time has elapsed, the timepiece is resynchronized with a time standard and the error E accumulated by the timepiece since the previous synchronization is calculated. The accumulated error, E, is divided by the number of adjustment intervals elapsed since the previous synchronizing of the timepiece, N, to obtain an accuracy adjustment factor. Then, at a specified time interval during each subsequent adjustment interval, the timekeeping frequency is adjusted by the amount of the accuracy adjustment factor to produce a resultant adjustment interval which equals an ideal time period.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: February 10, 1998
    Inventor: T. Earl Poulson
  • Patent number: 5596554
    Abstract: A manual set operation is described for a timepiece where a single switch is used to select categories and values for setting timekeeping quantities. The timepiece is implemented using a CMOS microcontroller integrated circuit and employs a matrix liquid crystal display to display time and calendar information one character at a time, in a slide-show manner.
    Type: Grant
    Filed: June 4, 1993
    Date of Patent: January 21, 1997
    Inventor: Hubert W. Hagadorn
  • Patent number: 5546363
    Abstract: A commercially available clock IC which is easily influenced by a temperature change or the like is used as it is, thereby easily allowing the clock IC to function as a high precision clock IC. A high precision oscillator is provided separately from a clock circuit as a clock IC. On the basis of a clock signal from the high precision oscillator, a predetermined time, for example, one minute is measured by a high precision clock control circuit. A correction signal is transmitted to the clock circuit as a clock IC from a high precision control circuit every measurement of such a predetermined time, thereby allowing the correcting operation of the time information to be executed. The clock circuit is, consequently, made operative at a precision of the high precision oscillating circuit.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: August 13, 1996
    Assignee: Fujitsu Limited
    Inventors: Jun Funaki, Shoji Tenma
  • Patent number: 5481507
    Abstract: To produce a time-base signal for timekeeping, an oscillator circuit generates an oscillator clock signal, which is counted cyclically with a programmable cycle length to establish a time-base cycle. The time-base signal is set and reset once in each time-base cycle. The oscillator clock signal is also counted with a fixed cycle length to establish an adjustment cycle, which is longer than the time-base cycle. In each adjustment cycle, the length of one or more time-base cycles is altered by a total amount determined by adjustment data stored in a non-volatile memory, then the time-base cycle length is restored to its nominal value. The average frequency of the time-base signal can be adjusted by writing appropriate adjustment data in the non-volatile memory.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: January 2, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yutaka Suzuki, Takumi Ishida, Masaharu Hayakawa
  • Patent number: 5440313
    Abstract: A GPS-based frequency/time source of the present invention provides an accurate, traceable low cost reference. In particular, the GPS-based frequency/time source includes a GPS receiver, a variable frequency oscillator and a micro processor. The GPS receiver receives and produces as output signals GPS information, whereas the variable frequency oscillator has a frequency control input terminal and produces an output frequency signal, and is coupled to the GPS receiver. The micro processor is coupled to receive the output signals produced by the GPS receiver and produces an error signal indicative of a difference in frequency between GPS synchronized frequency and the output frequency signal of the variable frequency oscillator. Circuitry is responsive to the error signal to produce an electronic frequency control signal, which is applied to the frequency control input of the variable frequency oscillator so as to cause the difference in frequency to be reduced.
    Type: Grant
    Filed: May 27, 1993
    Date of Patent: August 8, 1995
    Assignee: Stellar GPS Corporation
    Inventors: Terry N. Osterdock, David C. Westcott, Quyen D. Hua
  • Patent number: 5412624
    Abstract: A system and method for controlling time-critical functions by dynamically adjusting the interrupt frequency of a microprocessor. Interrupts are generated at a predetermined frequency. Time-critical functions are then performed in response to the interrupts. The interval is adjusted based on timing data from a substantially accurate source. Where the interval is measured in terms of clock pulses, a non-integer number of pulses per interval is attained by varying the number of pulses per interval so that the average over a number of intervals is equal to the non-integer number of pulses per interval. The interval is further adjusted using a selected damping coefficient to eliminate an underdamped condition.
    Type: Grant
    Filed: October 13, 1993
    Date of Patent: May 2, 1995
    Assignee: ABB Power T & D Company, Inc.
    Inventor: Thomas M. Yocom
  • Patent number: 5375105
    Abstract: An adjustable vibrations counter (20) and an elapsed time counter and switch (18) that select and adjust one second durations, the adjustment depending on whether the timekeeping rate of a watch or clock is fast or slow. The adjustable vibrations counter provides for an increase or decrease in the number of crystal (12) vibrations that are counted during each adjusted one second duration. The elapsed time counter and switch provides for the number of seconds that are selected for adjustment during each hour or day.A slide switch (22) or other means for changing the number of crystal vibrations that are counted during an adjusted one second duration, thus providing the timekeeping rate regulation. A display (28) of the amount of timekeeping rate adjustment that has been entered into a watch or clock.
    Type: Grant
    Filed: July 20, 1993
    Date of Patent: December 20, 1994
    Inventor: Raymond J. Borowski
  • Patent number: 5274545
    Abstract: A device and method provide for an accurate output from a unit, such as an oscillator and/or clock providing an output indicative of frequency and/or time. The device includes a processing section having a microprocessor that develops a model characterizing the performance of the device, including establishing predicted accuracy variations, and the model is then used to correct the unit output. An external reference is used to provide a reference input for updating the model, including updating of predicted variations of the unit, by comparison of the reference input with the unit output. The ability of the model to accurately predict the performance of the unit improves as additional updates are carried out, and this allows the interval between the updates to be lengthened and/or the overall accuracy of the device to be improved. The accuracy of the output is thus adaptively optimized in the presence of systematic and random variations.
    Type: Grant
    Filed: April 3, 1992
    Date of Patent: December 28, 1993
    Assignee: The United States of America as represented by the Secretary of Commerce
    Inventors: David W. Allan, Judah Levine, Dicky D. Davis, Marc A. Weiss
  • Patent number: 5255247
    Abstract: An integrated circuit for an electronic timepiece includes at least one semiconductor nonvolatile memory device. Reference data can be checked across a pair of output terminals prior to being stored in at least one EPROM to check the accuracy and acceptability of the reference data for driving a motor of the timepiece. The reference data once written into the EPROM serves as control data. Both the reference data and control data are used for controlling at least one function of the timepiece. The control data also can be checked across the output terminals to determine its accuracy and acceptability for driving the motor. Testing of the reference data and control data can be performed on a faster than real time basis.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: October 19, 1993
    Assignee: Seiko Epson Corporation
    Inventor: Tatsuo Moriya
  • Patent number: 5253229
    Abstract: An integrated circuit for an electronic timepiece includes at least one semiconductor nonvolatile memory device. Reference data can be checked across a pair of output terminals prior to being stored in at least one EPROM to check the accuracy and acceptability of the reference data for driving a motor of the timepiece. The reference data once written into the EPROM serves as control data. Both the reference data and control data are used for controlling at least one function of the timepiece. The control data also can be checked across the output terminals to determine its accuracy and acceptability for driving the motor. Testing of the reference data and control data can be performed on a faster than real time basis.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: October 12, 1993
    Assignee: Seiko Epson Corporation
    Inventor: Tatsuo Moriya
  • Patent number: 5218694
    Abstract: A dual selection system for a reference frequency for use in a clock comprising a microcomputer for controlling the whole system and outputting a switching signal and frequency-demultiplying signals. A system oscillator produces an oscillation signal of 4.194304 MHz. A system frequency-demultiplier for frequency-dividing an output of a first buffer to apply a system clock signal to the microcomputer. A clock oscillator produces an oscillation signal of 32.768 KHz, and a clock frequency-demultiplier for frequency-dividing an output of a second buffer applies a clock signal of 1 Hz for clock to the microcomputer.When an option is selected, a system oscillation signal of 4.194304 MHz is selected and frequency-demultiplied by 2.sup.22 to a clock signal of 1 Hz for a clock. When that the option is not selected, the clock oscillation signal of 32.768 KHz is frequency-divided by 2.sup.15 to a clock signal of 1 Hz for the clock.
    Type: Grant
    Filed: July 29, 1991
    Date of Patent: June 8, 1993
    Assignee: Goldstar Co., Ltd.
    Inventor: Byung H. Lee
  • Patent number: 5128909
    Abstract: A system to measure time based on the output of a plurality of clocks employs a common oscillator, rather than a frequency synthesizer. Phase differences between a plurality of clocks are measured by mixing the output from each clock with the output of the common oscillator and detecting the zero crossing of each of the resulting beat signals. The zero crossings are counted and used to start and stop time interval counters, which count the time intervals between zero crossings of the beat signals from different clocks. The output of one of the clocks is used to provide a time base. The output of the first clock is input to a divider, and the divided signal used to start the first of the time interval counters. The number of zero crossings of the divided signal are also counted so that the relative frequency of the common oscillator can be determined. The output of the divider can be synchronized with an external clock.
    Type: Grant
    Filed: August 17, 1990
    Date of Patent: July 7, 1992
    Assignee: Ball Corporation
    Inventor: Samuel R. Stein
  • Patent number: 4953148
    Abstract: Improved atomic clocks and frequency standards of the type where the frequency of an oscillator is stabilized by locking via a phase lock loop to an atomic resonator and where the output of the clock is taken from this oscillator. Protective means are provided to maintain a high accuracy when such clock is exposed to a strong magnetic field. The stabilization is based on two magnetic "C"-fields which are controlled and adjusted to maintain the accuracy of the clock.
    Type: Grant
    Filed: May 5, 1989
    Date of Patent: August 28, 1990
    Inventors: Alexander Lepek, Avinoam Stern
  • Patent number: 4943955
    Abstract: An atomic clock of the type comprising a quartz oscillator, a tube contaig a material, the atoms of which have an hyperfine spectral transition, control means capable of generating, from the quartz oscillator, a control signal of a frequency that corresponds to the hyperfine spectral transition, and of applying this control signal to the tube to cause interaction between this signal and the atoms of the material contained in the tube, and feedback means that are sensitive to the response of the tube and are adapted to modifying the frequency of the quartz oscillator so as to substantially center the frequency of the control signal on the frequency of the hyperfine spectral transition, wherein the control means are adapted to cyclically generate test signals, the controlled frequency of which is located outside the Ramsey peak.
    Type: Grant
    Filed: March 2, 1989
    Date of Patent: July 24, 1990
    Assignee: Societe d'Etudes, Recherches et Constructions Electroniques - Sercel
    Inventors: Jean Rabian, Jean-Claude Potet, Michel Buchon
  • Patent number: 4933920
    Abstract: The sidereal clock comprises a digital clock portion having a 60-Hz pulse source operating at line frequency of 60-Hz. It contains a means for periodically changing logic state at the 50/60-Hz select input of the prescale counter so that the digital clock portion is periodically changed during a period equal to 2922 clock pulses from the 60 Hz operation mode to the 50 Hz operation mode for a time interval equal to 40 clock pulses. During this time interval the prescale counter actually registers 6 counts for every 5 pulses received so that the digital clock portion runs fast by a factor of 2930/2922 and measures sidereal time. The means for changing logic state at the 50/60-Hz select input may comprise a ripple counter connected electrically to a plurality of gating circuits of first and second gating integrated circuits and a monostable multivibrator all of which are energized by the DC of the digital clock portion.
    Type: Grant
    Filed: December 19, 1988
    Date of Patent: June 12, 1990
    Inventor: Irwin Sternberg
  • Patent number: 4921467
    Abstract: A local oscillator for a radio receiver includes a voltage controlled oscillator (VCO), a decoder and controller for providing a control voltage to the VCO, an error detector circuit for detecting an error in the frequency of the VCO on the basis of a received signal processed with the oscillating signal from the VCO, a temperature probe and a memory. The local oscillator is initially set up during manufacture by detecting any errors in the frequency at selected temperatures, and storing data in the memory indicative of the control voltage required to compensate for the frequency error for each temperature. In operation the decoder and controller applies the appropriate control voltage to the VCO on the basis of the data stored in the memory relative to the temperature detected by the temperature probe.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: May 1, 1990
    Assignee: Multitone Electronics PLC
    Inventor: Alexander P. Lax
  • Patent number: 4903251
    Abstract: A microcontroller, software-based time-of-day clock compensates for inaccurate oscillator frequency by periodically correcting the time-of-day value using a calibration offset measured by manufacturing test equipment and permanently stored in nonvolatile memory. A high degree of time keeping accuracy is achieved without the use of trimming capacitors or presorted piezoelectric crystals in the oscillator. Furthermore, frequency error compensation is incorporated into the microcontroller system without requiring a significant amount of processing time overhead.
    Type: Grant
    Filed: September 5, 1989
    Date of Patent: February 20, 1990
    Assignee: Ford Motor Company
    Inventor: Max C. Chapman
  • Patent number: 4845692
    Abstract: A clocking device of substantially constant stability for short-term and long-term measurements. This clocking device comprises first generators of a clocking signal with substantially constant stability for short-term measurements, and second generators of a clocking signal of constant stability for long-term measurements. Means for the automatic locking of one of the said first or second clocking signals to the other clocking signal are provided, and enable the automatic frequency and/or phase locking of said signals. The automatic locking means have a time constant corresponding to the transition zone between the short-term and long-term measurements. The device can be applied in the high-precision time-measuring instruments industry and to air and space navigation instruments.
    Type: Grant
    Filed: April 18, 1988
    Date of Patent: July 4, 1989
    Assignee: Centre National D'Etudes Spatiales
    Inventors: Jacques Groslambert, Michel Brunet
  • Patent number: 4763309
    Abstract: This programming arrangement for a non-volatile memory incorporated in the inner circuit of a timepiece for adjusting the frequency of the time base thereof includes a support provided with a connector to be plugged in in place of the energy cell. The rate of division of the frequency divider is adjusted by the introduction into the memory of a number k representative of the frequency difference between the time base frequency and a standard frequency. To effect this the arrangement comprises an electronic circuit external to the timepiece and which is coupled thereto by the connector. The electronic circuit introduces the number k into certain predetermined stages of the divider. When such number k is thus introduced the state of such stages is blocked by the inner circuit of the timepiece such state then being transferred into the non-volatile memory.
    Type: Grant
    Filed: July 9, 1987
    Date of Patent: August 9, 1988
    Assignee: EM Microelectronic-Marin SA
    Inventor: Arthur Descombes