Patents by Inventor Mao Chuan Chien

Mao Chuan Chien 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).

  • Patent number: 9618540
    Abstract: A current sensing module and a power conversion apparatus and an electronic apparatus using the same are provided. The current sensing module is suitable for detecting a first load current flowing through a first load. The current sensing module includes a sampling stage circuit and an output stage circuit. The sampling stage circuit couples across the first load and selectively exchanges coupling nodes between the sampling stage circuit and the first load by a multiplex switching means, so as to sample the first load current flowing along a first direction or a second direction, and thus generate a sampling signal. The output stage circuit is coupled to the sampling stage circuit and switches coupling nodes between the output stage circuit and the output terminal of the sampling stage circuit, so as to generate a current indication signal indicating the magnitude of the first load current according to the sampling signal.
    Type: Grant
    Filed: August 19, 2015
    Date of Patent: April 11, 2017
    Assignee: Midastek Microelectronic Inc.
    Inventors: Muh-Rong Yang, Well-Chen Chua, Mao-Chuan Chien, Chi-Chien Lin
  • Publication number: 20160344290
    Abstract: A current sensing module and a power conversion apparatus and an electronic apparatus using the same are provided. The current sensing module is suitable for detecting a first load current flowing through a first load. The current sensing module includes a sampling stage circuit and an output stage circuit. The sampling stage circuit couples across the first load and selectively exchanges coupling nodes between the sampling stage circuit and the first load by a multiplex switching means, so as to sample the first load current flowing along a first direction or a second direction, and thus generate a sampling signal. The output stage circuit is coupled to the sampling stage circuit and switches coupling nodes between the output stage circuit and the output terminal of the sampling stage circuit, so as to generate a current indication signal indicating the magnitude of the first load current according to the sampling signal.
    Type: Application
    Filed: August 19, 2015
    Publication date: November 24, 2016
    Applicant: Midastek Microelectronic Inc.
    Inventors: Muh-Rong Yang, Well-Chen Chua, Mao-Chuan Chien, Chi-Chien Lin
  • Patent number: 8129965
    Abstract: A low dropout regulator includes an error amplifier, an N-type depletion MOSFET, a first switch, a second switch, a low-pass filter resistor, and a low-pass filter capacitor. By switching on both the first switch and the second switch, a voltage level of an output node at a negative input terminal of the error amplifier may be rapidly raised to be close to and lower than a voltage level of an input node at a gate of the N-type depletion MOSFET. Both the first switch and the second switch are then switched off immediately so that the voltage level of the output node is gradually raised to be equal to the voltage level of the input node through the low-pass filter resistor.
    Type: Grant
    Filed: December 1, 2009
    Date of Patent: March 6, 2012
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Shun-Hau Kao, Mao-Chuan Chien, Chih-Liang Huang
  • Patent number: 7906945
    Abstract: A soft-start voltage circuit includes an operational amplifier, a first and a second capacitors, a first and a second switches, and a voltage level shifter. The operational amplifier includes a positive end, a negative end, and an output end coupled to the negative end of the operational amplifier for outputting the soft-start voltage. The voltage level shifter is coupled between the first capacitor and the positive end of the operational amplifier for shifting a level of the voltage on the first capacitor. The first switch is coupled between the first and the second capacitors for coupling the first and the second capacitors according to the clock. The second switch is coupled between the second capacitor and the negative end of the operational amplifier for coupling the second capacitor and the negative end of the operational amplifier according to the inverted clock.
    Type: Grant
    Filed: November 17, 2008
    Date of Patent: March 15, 2011
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Shun-Hau Kao, Mao-Chuan Chien
  • Patent number: 7852054
    Abstract: An over current protection circuit for low dropout regulator comprises a sense transistor, a sense resistor, an operational amplifier and a first transistor. The sense transistor senses the current flowing through the power transistor. The sense resistor is coupled to the sense transistor and shares the same current flowing through the sense transistor. The operational amplifier outputs a control signal according to the voltage across the sense resistor and a reference voltage. The first transistor controls the power transistor according to the control signal.
    Type: Grant
    Filed: September 23, 2008
    Date of Patent: December 14, 2010
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Shun Hau Kao, Mao Chuan Chien
  • Publication number: 20100308781
    Abstract: A low dropout regulator includes an error amplifier, an N-type depletion MOSFET, a first switch, a second switch, a low-pass filter resistor, and a low-pass filter capacitor. By switching on both the first switch and the second switch, a voltage level of an output node at a negative input terminal of the error amplifier may be rapidly raised to be close to and lower than a voltage level of an input node at a gate of the N-type depletion MOSFET. Both the first switch and the second switch are then switched off immediately so that the voltage level of the output node is gradually raised to be equal to the voltage level of the input node through the low-pass filter resistor.
    Type: Application
    Filed: December 1, 2009
    Publication date: December 9, 2010
    Inventors: Shun-Hau Kao, Mao-Chuan Chien, Chih-Liang Huang
  • Patent number: 7741820
    Abstract: A PWM controller for controlling a switching voltage regulator comprises a first comparator, a second comparator and a third comparator. The first comparator is configured to detect voltages of a first node and a second node so as to determine whether to stop the PWM controller. The PWM controller is stopped if a first potential is lower than a threshold, and the first potential derives from the voltage of the first node by a level shift of a first voltage difference. The second comparator is configured to detect the voltage of the first node and then to compare the voltage with a power reference voltage so as to determine whether the PWM controller receives necessary power. The third comparator is configured to compare the voltage of the second node with an enable reference voltage so as to determine whether to disable the PWN controller.
    Type: Grant
    Filed: September 2, 2008
    Date of Patent: June 22, 2010
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Hsiang Lin Huang, Kent Huang, Mao Chuan Chien, Shun Hau Kao
  • Publication number: 20100073071
    Abstract: An over-temperature detecting circuit includes a band-gap circuit for generating a temperature-drop-dependent voltage and a reference voltage not varying with the temperature, a transistor coupled to the band-gap circuit for generating a temperature-rise-dependent current according to the temperature-drop-dependent voltage, a resistor coupled to the transistor for generating a temperature-rise-dependent voltage according to the temperature-rise-dependent current, and a comparator coupled to the band-gap circuit and the resistor for generating a thermal shutdown signal according to the reference voltage and the temperature-rise-dependent voltage.
    Type: Application
    Filed: November 21, 2008
    Publication date: March 25, 2010
    Inventors: Mao-Chuan Chien, Shun-Hau Kao
  • Publication number: 20100060248
    Abstract: A soft-start voltage circuit includes an operational amplifier, a first and a second capacitors, a first and a second switches, and a voltage level shifter. The operational amplifier includes a positive end, a negative end, and an output end coupled to the negative end of the operational amplifier for outputting the soft-start voltage. The voltage level shifter is coupled between the first capacitor and the positive end of the operational amplifier for shifting a level of the voltage on the first capacitor. The first switch is coupled between the first and the second capacitors for coupling the first and the second capacitors according to the clock. The second switch is coupled between the second capacitor and the negative end of the operational amplifier for coupling the second capacitor and the negative end of the operational amplifier according to the inverted clock.
    Type: Application
    Filed: November 17, 2008
    Publication date: March 11, 2010
    Inventors: Shun-Hau Kao, Mao-Chuan Chien
  • Publication number: 20100026254
    Abstract: An over current protection circuit for low dropout regulator comprises a sense transistor, a sense resistor, an operational amplifier and a first transistor. The sense transistor senses the current flowing through the power transistor. The sense resistor is coupled to the sense transistor and shares the same current flowing through the sense transistor. The operational amplifier outputs a control signal according to the voltage across the sense resistor and a reference voltage. The first transistor controls the power transistor according to the control signal.
    Type: Application
    Filed: September 23, 2008
    Publication date: February 4, 2010
    Applicant: ADVANCED ANALOG TECHNOLOGY, INC.
    Inventors: SHUN HAU KAO, MAO CHUAN CHIEN
  • Publication number: 20100019747
    Abstract: A low dropout regulator comprises a depletion mode NMOS transistor, a switch and an error amplifier. The source electrode of the depletion type NMOS transistor is coupled to a feedback circuit. The switch, controlled by a control signal, connects a supply voltage to the drain electrode of the depletion mode NMOS transistor. The non-inverting input terminal of the error amplifier is coupled to a reference voltage. The output terminal of the error amplifier is coupled to the gate electrode of the depletion mode NMOS transistor. The inverting input terminal of the error amplifier is coupled to the feedback circuit.
    Type: Application
    Filed: September 23, 2008
    Publication date: January 28, 2010
    Applicant: ADVANCED ANALOG TECHNOLOGY, INC.
    Inventors: SHUN HAU KAO, MAO CHUAN CHIEN
  • Patent number: 7622902
    Abstract: An LDO with over-current protection includes a first and a second P-type transistor, a sensing resistor, a comparator, and an error amplifier. The channel aspect ratio of the first P-type transistor is much higher than that of the second P-type transistor. The first P-type transistor generates output voltage source according to input voltage source and current control signal. The sensing resistor is coupled among the input voltage source, the second P-type transistor, and the comparator, providing a sensing voltage. The comparator generates a current limiting signal according to first reference voltage and the sensing voltage. When the current limiting signal enables the error amplifier, the error amplifier adjusts voltage of the current control signal according to second reference voltage and voltage divided from the output voltage source; when the current limiting signal disables the error amplifier, voltage of the current control signal is not adjusted.
    Type: Grant
    Filed: November 17, 2008
    Date of Patent: November 24, 2009
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Shun-Hau Kao, Mao-Chuan Chien
  • Patent number: 7612549
    Abstract: An LDO with fast current limit includes P-type transistor, an error amplifier, an adjustable reference voltage circuit for generating an adjustable reference voltage, and an N-type transistor. The P-type transistor includes a first end coupled to the input voltage source, a second end for outputting an output voltage source, and a control end for receiving a current control signal in order to control the current of the output voltage source. The error amplifier generates the current control signal according to the reference voltage and a voltage divided from the output voltage source. N-type transistor includes a first end coupled to the output end of the error amplifier, a second end coupled to the input voltage source, and a control end for receiving the adjustable reference voltage. When the N-type transistor is turned on, the voltage of the current control signal is clamped by the adjustable reference voltage.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: November 3, 2009
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Shun-Hau Kao, Mao-Chuan Chien
  • Publication number: 20090189661
    Abstract: A pulse width modulation controller comprises a disabling unit, a level sensor and an over current protector. These three devices are all coupled to a multi-function node for accomplishing a disable function, input level sensing, and over-current protection, respectively.
    Type: Application
    Filed: April 14, 2008
    Publication date: July 30, 2009
    Applicant: ADVANCED ANALOG TECHNOLOGY, INC.
    Inventors: Shun Hau KAO, Kent HUANG, Hsiang Lin HUANG, Mao Chuan CHIEN
  • Publication number: 20090189585
    Abstract: A PWM controller for controlling a switching voltage regulator comprises a first comparator, a second comparator and a third comparator. The first comparator is configured to detect voltages of a first node and a second node so as to determine whether to stop the PWM controller. The PWM controller is stopped if a first potential is lower than a threshold, and the first potential derives from the voltage of the first node by a level shift of a first voltage difference. The second comparator is configured to detect the voltage of the first node and then to compare the voltage with a power reference voltage so as to determine whether the PWM controller receives necessary power. The third comparator is configured to compare the voltage of the second node with an enable reference voltage so as to determine whether to disable the PWN controller.
    Type: Application
    Filed: September 2, 2008
    Publication date: July 30, 2009
    Applicant: ADVANCED ANALOG TECHNOLOGY, INC.
    Inventors: HSIANG LIN HUANG, KENT HUANG, MAO CHUAN CHIEN, SHUN HAU KAO
  • Publication number: 20090167274
    Abstract: A PWM controller applied to a switching voltage regulator comprises a disabling circuit, a power-sensing circuit, an over-current protection circuit and a PWM logic circuit. The disabling circuit is connected to an external frequency compensation circuit for detecting a voltage used to stop the operation of the PWM controller. The power-sensing circuit is configured to stop the operation of the PWM controller if the input voltage of the high side switch is lower than a threshold. The over-current protection circuit is configured to monitor current flowing through the output circuit, and the over-current protection circuit generates an over-current protection signal when the current exceeds a threshold. The PWM logic circuit is connected to the outputs of the disabling circuit, power-sensing circuit and over-current protection circuit.
    Type: Application
    Filed: September 2, 2008
    Publication date: July 2, 2009
    Applicant: ADVANCED ANALOG TECHNOLOGY, INC.
    Inventors: MAO CHUAN CHIEN, KENT HUANG, HSIANG LIN HUANG, SHUN HAU KAO
  • Patent number: 7551008
    Abstract: The circuit for fixing the peak current of an inductor includes an operating current, a ramp-type boost converter and a comparator. The magnitude of the operating current is proportional to that of the voltage source of the inductor. The ramp-type boost converter is connected to the operating current. One input end of the comparator is connected to a reference voltage, and the other end is connected to the output of the ramp-type boost converter. The output of the comparator is connected to the gate of a power transistor, which controls the turn-on time of the inductor.
    Type: Grant
    Filed: March 19, 2007
    Date of Patent: June 23, 2009
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Mao Chuan Chien, Chu Yu Chu, Yu Min Sun
  • Patent number: 7501908
    Abstract: The oscillation circuit includes an output current mirror, a P-N complementary current mirror, a P-type current mirror and an N-type current mirror. The P-N complementary current mirror has the same structure as the output current mirror but has current that is only 1/k times the current of the output current mirror, wherein k is greater than 1. The P-type current mirror connects to the P-N complementary current mirror, and has current that is m times the current of the P-N complementary current mirror, where m is greater than 1. The N-type current mirror has one end connected to the P-type current mirror and another end connected to the output current mirror. The N-type current mirror has current that is n times the current of the P-type current mirror, where m × n k ? 1 , and n is greater than 1.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: March 10, 2009
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Mao Chuan Chien, Yu Min Sun, Chu Yu Chu
  • Patent number: 7456622
    Abstract: The low voltage circuit for starting up a synchronous step-up DC/DC converter, which connects to a voltage source through an inductor, includes a P-type power transistor, an N-type power transistor and a controller. The P-type power transistor includes a body diode, and one end of the P-type power transistor acts as a power source of an oscillator. The N-type power transistor connects the P-type power transistor in series, and both of the power transistors are not enabled at the same time. The oscillator electrically connects to the controller, which enables the P-type power transistor at initialization time, and enables the N-type power transistor a period after the initialization time.
    Type: Grant
    Filed: April 10, 2007
    Date of Patent: November 25, 2008
    Assignee: Advanced Analog Technology, Inc.
    Inventors: Mao Chuan Chien, Chu Yu Chu, Yu Min Sun
  • Publication number: 20080231386
    Abstract: The oscillation circuit includes an output current mirror, a P-N complementary current mirror, a P-type current mirror and an N-type current mirror. The P-N complementary current mirror has the same structure as the output current mirror but has current that is only 1/k times the current of the output current mirror, wherein k is greater than 1. The P-type current mirror connects to the P-N complementary current mirror, and has current that is m times the current of the P-N complementary current mirror, where m is greater than 1. The N-type current mirror has one end connected to the P-type current mirror and another end connected to the output current mirror. The N-type current mirror has current that is n times the current of the P-type current mirror, where m × n k ? 1 , and n is greater than 1.
    Type: Application
    Filed: March 29, 2007
    Publication date: September 25, 2008
    Applicant: ADVANCED ANALOG TECHNOLOGY, INC.
    Inventors: Mao Chuan Chien, Yu Min Sun, Chu Yu Chu