Patents by Inventor Chung-Kai Chow
Chung-Kai Chow has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20200292666Abstract: A multi-chip MIMO radar system includes a plurality of transmitters and a plurality of receivers. Each of the pluralities of transmitters and receivers are arranged across a plurality of chips. The multi-chip MIMO radar system is configured to provide an exemplary chip synchronization such that the transmitters and receivers of each chip of the radar system are synchronized with the transmitters and receivers of every other chip of the radar system.Type: ApplicationFiled: March 12, 2020Publication date: September 17, 2020Inventors: Monier Maher, Marius Goldenberg, Chung-Kai Chow, Frederick Rush, Otto A. Schmid
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Patent number: 7224216Abstract: A chopping amplifier and method for chopping an input signal are disclosed. The chopping amplifier and method utilize at least two chopping amplifier stages. A chopping operation of an input signal is segmented across two or more chopping amplifier stages, and the two or more chopping amplifier stages are responsive to a master controller. Chop clock signals of the chopping amplifier stages are staggered so that they have non-overlapping periods and at least one of the chopping amplifier stages is not operating in an open loop at any given time. The non-overlapping periods are periodic so that a master chop clock of the master controller can be operated at a lower chop clock frequency. For every doubling of N number of chopping amplifier stages, magnitudes of chopping artifacts and aliased components are each respectively reduced by 3 dB.Type: GrantFiled: June 19, 2006Date of Patent: May 29, 2007Assignee: Cirrus Logic, Inc.Inventors: Karl Thompson, John L. Melanson, Chung-Kai Chow, Ammisetti V. Prasad
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Patent number: 7218612Abstract: A network arrangement uses a poll select control protocol and a loop back arrangement at each node for equalizing transmission delay from each node to a central station. Delays at each node can be adjusted to start timing in response to a broadcast signal indicating an amount of delay to be applied from the start of a synchronization interval to the beginning of transmission of data collected at the nodes. The arrangement is particularly useful in the field of data acquisition and particularly in the area of seismic sensing.Type: GrantFiled: June 9, 2003Date of Patent: May 15, 2007Assignee: Cirrus Logic, Inc.Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow
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Patent number: 7154260Abstract: A precision measurement unit (PMU) includes a force amplifier selectively providing either a forcing voltage or a forcing current to a device under test via an output force terminal. A low limit voltage clamp and a high limit voltage clamp are operatively coupled to the output force terminal. The low and high limit voltage clamps are each responsive to user programming to define respective low and high voltage limits at the output force terminal. Upon detection of a reversal of said user programming, the operation of the low and high limit voltage clamps is disabled. More particularly, a comparator is adapted to compare the low and high voltage limits and provide a corresponding disabling signal if the high voltage limit is lower than the low voltage limit.Type: GrantFiled: October 19, 2004Date of Patent: December 26, 2006Assignee: Semtech CorporationInventor: Chung-Kai Chow
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Publication number: 20060232331Abstract: A chopping amplifier and method for chopping an input signal are disclosed. The chopping amplifier and method utilize at least two chopping amplifier stages. A chopping operation of an input signal is segmented across two or more chopping amplifier stages, and the two or more chopping amplifier stages are responsive to a master controller. Chop clock signals of the chopping amplifier stages are staggered so that they have non-overlapping periods and at least one of the chopping amplifier stages is not operating in an open loop at any given time. The non-overlapping periods are periodic so that a master chop clock of the master controller can be operated at a lower chop clock frequency. For every doubling of N number of chopping amplifier stages, magnitudes of chopping artifacts and aliased components are each respectively reduced by 3 dB.Type: ApplicationFiled: June 19, 2006Publication date: October 19, 2006Inventors: Karl Thompson, John Melanson, Chung-Kai Chow, Ammisetti Prasad
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Patent number: 7091771Abstract: A chopping amplifier and method for chopping an input signal are disclosed. The chopping amplifier and method utilize at least two chopping amplifier stages. A chopping operation of an input signal is segmented across two or more chopping amplifier stages, and the two or more chopping amplifier stages are responsive to a master controller. Chop clock signals of the chopping amplifier stages are staggered so that they have non-overlapping periods and at least one of the chopping amplifier stages is not operating in an open loop at any given time. The non-overlapping periods are periodic so that a master chop clock of the master controller can be operated at a lower chop clock frequency. For every doubling of N number of chopping amplifier stages, magnitudes of chopping artifacts and aliased components are each respectively reduced by 3 dB.Type: GrantFiled: October 16, 2003Date of Patent: August 15, 2006Assignee: Cirrus Logic, Inc.Inventors: Karl Thompson, John L. Melanson, Chung-Kai Chow, Ammisetti V. Prasad
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Publication number: 20060082359Abstract: A precision measurement unit (PMU) includes a force amplifier selectively providing either a forcing voltage or a forcing current to a device under test via an output force terminal. A low limit voltage clamp and a high limit voltage clamp are operatively coupled to the output force terminal. The low and high limit voltage clamps are each responsive to user programming to define respective low and high voltage limits at the output force terminal. Upon detection of a reversal of said user programming, the operation of the low and high limit voltage clamps is disabled. More particularly, a comparator is adapted to compare the low and high voltage limits and provide a corresponding disabling signal if the high voltage limit is lower than the low voltage limit.Type: ApplicationFiled: October 19, 2004Publication date: April 20, 2006Inventor: Chung-Kai Chow
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Patent number: 6980037Abstract: A power on reset circuit, preferably for an integrated circuit, detects application of voltage, starts a phase locked loop one application of voltage is detected but inhibits all clock used for digital logic operations until voltage stability is achieved. If a switched converter is used, the duty cycle of the switched converter is held at unity for a period of time before it is set to that needed to achieve the desired chip operating voltage. Clocks controlling other circuits can be released in stages after the duty cycle of the switched converter is set to its operating voltage level.Type: GrantFiled: September 16, 1998Date of Patent: December 27, 2005Assignee: Cirrus Logic, Inc.Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow
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Patent number: 6828775Abstract: A high-impedance mode is provided for an output of a precision measurement unit (PMU). The PMU includes an output amplifier that provides a forcing voltage or current to a device under test. When the high-impedance mode is activated, the output amplifier is decoupled from an output terminal of the PMU and the output amplifier is disabled. This prevents the voltage on the output terminal from rising in an uncontrolled manner, and prevents current spikes from forming on the output terminal when connected to a device under test. The high-impedance mode is deactivated to permit connection of the PMU to another device under test by re-coupling the output amplifier to the output terminal and enabling operation of the output amplifier.Type: GrantFiled: February 21, 2003Date of Patent: December 7, 2004Assignee: Semtech CorporationInventors: Chung-Kai Chow, Jeffrey Blackburn
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Publication number: 20040164724Abstract: A high-impedance mode is provided for an output of a precision measurement unit (PMU). The PMU includes an output amplifier that that provides a forcing voltage or current to a device under test. When the high-impedance mode is activated, the output amplifier is decoupled from an output terminal of the PMU and the output amplifier is disabled. This prevents the voltage on the output terminal from rising in an uncontrolled manner, and prevents current spikes from forming on the output terminal when connected to a device under test. The high-impedance mode is deactivated to permit connection of the PMU to another device under test by re-coupling the output amplifier to the output terminal and enabling operation of the output amplifier.Type: ApplicationFiled: February 21, 2003Publication date: August 26, 2004Applicant: SEMTECH CORPORATIONInventors: Chung-Kai Chow, Jeffrey Blackburn
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Publication number: 20040140847Abstract: A chopping amplifier and method for chopping an input signal are disclosed. The chopping amplifier and method utilize at least two chopping amplifier stages. A chopping operation of an input signal is segmented across two or more chopping amplifier stages, and the two or more chopping amplifier stages are responsive to a master controller. Chop clock signals of the chopping amplifier stages are staggered so that they have non-overlapping periods and at least one of the chopping amplifier stages is not operating in an open loop at any given time. The non-overlapping periods are periodic so that a master chop clock of the master controller can be operated at a lower chop clock frequency. For every doubling of N number of chopping amplifier stages, magnitudes of chopping artifacts and aliased components are each respectively reduced by 3 dB.Type: ApplicationFiled: October 16, 2003Publication date: July 22, 2004Inventors: Karl Thompson, John L. Melanson, Chung-Kai Chow, Ammisetti V. Prasad
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Publication number: 20030202542Abstract: A network arrangement uses a poll select control protocol and a loop back arrangement at each node for equalizing transmission delay from each node to a central station. Delays at each node can be adjusted to start timing in response to a broadcast signal indicating an amount of delay to be applied from the start of a synchronization interval to the beginning of transmission of data collected at the nodes. The arrangement is particularly useful in the field of data acquisition and particularly in the area of seismic sensing.Type: ApplicationFiled: June 9, 2003Publication date: October 30, 2003Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow
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Patent number: 6594284Abstract: A network arrangement uses a poll select control protocol and a loop back arrangement at each node for equalizing transmission delay from each node to a central station. Delays at each node can be adjusted to start timing in response to a broadcast signal indicating an amount of delay to be applied from the start of a synchronization interval to the beginning of transmission of data collected at the nodes. The arrangement is particularly useful in the field of data acquisition and particularly in the area of seismic sensing.Type: GrantFiled: September 16, 1998Date of Patent: July 15, 2003Assignee: Cirrus Logic, Inc.Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow
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Patent number: 6546408Abstract: A sinc filter is implemented by partitioning 1 bit wide incoming data into multibit words. The multibit words are multiplied by respective coefficient sets. Some multibit words are twisted by inverting the bit order and the multiplied using the same coefficient sets used for untwisted words. Multiplications are implemented using either look up tables or logic and the filter is implemented using only shifts and additions. The sinc filter is particularly useful applications in the field of data acquisition and particularly in the area of seismic sensing.Type: GrantFiled: September 16, 1998Date of Patent: April 8, 2003Assignee: Cirrus Logic, Inc.Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow
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Publication number: 20020063588Abstract: Clocks on and off an integrated circuit chip are aligned to that clocks on the chip are synchronized to one of the rising and falling edges of a master clock and those off the chip are synchronized to the other of the rising and falling edges of the master clock. This permits a certain ease of interfacing circuits controlled by those clocks. Programmable clocks on the chip can be reprogrammed during operation to conserve power.Type: ApplicationFiled: September 16, 1998Publication date: May 30, 2002Inventors: JOEL PAGE, EDWIN DE ANGEL, WAI LAING LEE, LEI WANG, HONG ZHENG, CHUNG-KAI CHOW
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Publication number: 20020038324Abstract: A sinc filter is implemented by partitioning 1 bit wide incoming data into multibit words. The multibit words are multiplied by respective coefficient sets. Some multibit words are twisted by inverting the bit order and the multiplied using the same coefficient sets used for untwisted words. Multiplications are implemented using either look up tables or logic and the filter is implemented using only shifts and additions. The sinc filter is particularly useful applications in the field of data acquisition and particularly in the area of seismic sensing.Type: ApplicationFiled: September 16, 1998Publication date: March 28, 2002Inventors: JOEL PAGE, EDWIN DE ANGEL, WAI LAING LEE, LEI WANG, HONG ZHENG, CHUNG-KAI CHOW
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Patent number: 6337636Abstract: A data acquisition system has a central station connected to a plurality of nodes over a network. Each node is connected to receive signals from one or more sensors ad each is configured to have substantially the same transmission delay to said central station. The central station is configured to notify all nodes of an event time at which a data event, such as a seismic shot, occurred.Type: GrantFiled: September 16, 1998Date of Patent: January 8, 2002Assignee: Cirrus Logic, Inc.Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow
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Patent number: 6321246Abstract: A phase shifter is implemented using a polyphase filter. The filter is preferably a linear phase Finite Impulse Response (FIR) filter. The amount of delay imparted by the phase shifter is determined by a particular set of coefficients selected from a plurality of such coefficients. Storage requirements are reduced by taking advantage of symmetries in the coefficients for the filters. Memory requirements are further reduced by partitioning the polyphase filter into two polyphase filters and using one to set a rough delay amount and the other to set a fine delay amount between rough delay amount settings. The particular amount of delay may be set by an external synchronization signal.Type: GrantFiled: September 16, 1998Date of Patent: November 20, 2001Assignee: Cirrus Logic, Inc.Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow
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Patent number: 6317765Abstract: A decimation filter implements selective decimation ratios by arranging a plurality of sinc filters in different pipeline arrangements to produce the desired ratio. Power savings area achieved by implementing the sinc filters as FIR sinc filters and by implementing multiplications using look up tables. One approach uses a fixed first stage filter and one or more second stage sinc filters selected from the group comprising two 4th order, 5 tap sinc filters, a 4th order, 9 tap sinc filter; a 5th order, 6 tap sinc filter and a 6th order 7 tap sinc filter. The sinc filter is particularly useful applications in the field of data acquisition and particularly in the area of seismic sensing.Type: GrantFiled: September 16, 1998Date of Patent: November 13, 2001Assignee: Cirrus Logic, Inc.Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow
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Patent number: 6281718Abstract: A switched converter uses two series connected complementary CMOS devices and has a square wave source for activating one CMOS device while deactivating the other; and a break before make circuit connected between the square wave source and said complementary CMOS devices to ensure that one device is substantially completely off before the other device turns on. The switched converter is programmable as to frequency, phase and duty cycle.Type: GrantFiled: September 16, 1998Date of Patent: August 28, 2001Assignee: Cirrus Logic, Inc.Inventors: Joel Page, Edwin De Angel, Wai Laing Lee, Lei Wang, Hong Helena Zheng, Chung-Kai Chow