Variable Attenuator Patents (Class 327/308)
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Patent number: 8624654Abstract: An automatic step variable attenuator includes: a step variable attenuator attenuating a received signal of an electric wave signal in an attenuation amount corresponding to a control signal in a step-like style; a detector disposed in parallel with the step variable attenuator for input of the received signal of the electric wave signal, and converting an electric power of the received signal thus inputted into an intensity signal representing an intensity of the received signal; and a comparator portion generating the control signal corresponding to a result of comparison for differences between the intensity signal obtained from the detector and plural threshold values, and outputting the control signal thus generated to the step variable attenuator.Type: GrantFiled: July 18, 2012Date of Patent: January 7, 2014Assignee: Sony CorporationInventors: Noboru Sasho, Naoto Yoshikawa
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Patent number: 8618860Abstract: A circuit and method are provided for switching in a semiconductor based high power switch. Complementary p-type based transistors are utilized along insertion loss insensitive paths allowing biasing voltages to alternate between supply and ground, allowing for negative voltage supplies and blocking capacitors to be dispensed with, while improving performance.Type: GrantFiled: December 10, 2012Date of Patent: December 31, 2013Assignee: SiGe Semiconductor Inc.Inventors: Lui Lam, Hanching Fuh
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Patent number: 8614597Abstract: An apparatus comprising one or more series transistor network elements and a plurality of shunt circuits. The series transistor network may be configured to generate an output signal in response to (i) an input signal, (ii) a first bias signal, and (iii) a plurality of variable impedances. The plurality of shunt circuits may each be configured to generate a respective one of the variable impedances in response to a second bias signal. The output signal may have an attenuation that is equal to or less than the input power. The amount of the attenuation may be controlled by the first bias signal and the second bias signal. The series transistor elements and the plurality of shunt circuits may be configured as two or more transistors each having two or more gates.Type: GrantFiled: June 16, 2011Date of Patent: December 24, 2013Assignee: M/A-COM Technology Solutions Holdings, Inc.Inventor: Wen Hui Zhang
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Patent number: 8610458Abstract: An impedance control circuit includes a first impedance unit configured to terminate an impedance node using an impedance value that is determined by an impedance control code, a second impedance unit configured to terminate the impedance node using an impedance value that is determined by an impedance control voltage, a comparison circuit configured to compare a voltage level of the impedance node and a voltage level of a reference voltage, generate an up/down signal indicating whether the voltage at the impedance node is greater than the reference voltage, and generate the impedance control voltage that has a voltage level corresponding to a difference between the voltage at the impedance node and the reference voltage, and a counter unit configured to increase or decrease a value of the impedance control code in response to the up/down signal.Type: GrantFiled: April 13, 2012Date of Patent: December 17, 2013Assignee: Hynix Semiconductor Inc.Inventor: Ji-Wang Lee
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Patent number: 8610482Abstract: A highly reliable trimming circuit is provided. A rewritable trimming circuit is provided. A method for driving a highly reliable trimming circuit is provided. A method for driving a rewritable trimming circuit is provided. The trimming circuit includes a storage node connected to a source electrode or a drain electrode of a transistor whose off-state leakage current is extremely low and a transistor whose gate electrode is connected to the storage node. The trimming state of an element or a circuit connected in parallel to a source electrode and a drain electrode of the transistor whose gate electrode is connected to the storage node is controlled using the transistor whose off-state leakage current is extremely low.Type: GrantFiled: May 22, 2012Date of Patent: December 17, 2013Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventor: Makoto Kaneyasu
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Patent number: 8593316Abstract: A combined digital output system includes two quantization modules, a common mode counter, a differential mode counter, and a summing module. The quantization modules provide two digital signals, the common mode counter generates a common mode signal according to the digital signals, the differential mode counter generates a differential mode signal according to the two digital signals, and the summing module obtains the common mode signal and the differential mode signal, so as to generate a summing signal.Type: GrantFiled: June 10, 2011Date of Patent: November 26, 2013Assignee: Industrial Technology Research InstituteInventor: Robert Rieger
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Patent number: 8587358Abstract: Provided is a semiconductor integrated circuit including a variable resistor circuit of the small layout area, which is free from an error in resistance caused by ON-state resistances of switch elements for trimming, and is also free from power supply voltage dependence and temperature dependence. The semiconductor integrated circuit including a variable resistor circuit includes: a resistor circuit including a plurality of series-connected resistors; a selection circuit including a plurality of switch elements for selecting a connected number of the plurality of series-connected resistors; and a control circuit for controlling ON-state resistances of the plurality of switch elements. The control circuit controls the ON-state resistances of the plurality of switch elements so as to obtain a predetermined ratio to a resistance of the plurality of series-connected resistors of the resistor circuit.Type: GrantFiled: June 7, 2011Date of Patent: November 19, 2013Assignee: Seiko Instruments Inc.Inventor: Fumiyasu Utsunomiya
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Publication number: 20130285729Abstract: A semiconductor trimming circuit includes parallel coupled PMOS devices coupled in parallel with parallel coupled NMOS devices and an additional pair of dummy NMOS devices. The dummy NMOS devices are coupled in parallel with the NMOS devices. A trimming circuit for an internal clock source may be formed with an array of such switches for selecting one or more trimming capacitors of the trimming circuit. Such an array has a low leakage current and permits good trimming linearity.Type: ApplicationFiled: September 9, 2012Publication date: October 31, 2013Applicant: FREESCALE SEMICONDUCTOR, INCInventors: Xiuqiang Xu, Jie Jin, Yizhong Zhang
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Publication number: 20130278317Abstract: Switchable capacitive elements are disclosed, along with programmable capacitor arrays (PCAs). One embodiment of the switchable capacitive element includes a field effect transistor (FET) device stack, a first capacitor, and a second capacitor. The FET device stack is operable in an open state and in a closed state and has a plurality of FET devices coupled in series to form the FET device stack. The first capacitor and the second capacitor are both coupled in series with the FET device stack. However, the first capacitor is coupled to a first end of the FET device stack while the second capacitor is coupled to a second end opposite the first end of the FET device stack. In this manner, the switchable capacitive element can be operated without a negative charge pump, with decreased bias swings, and with a better power performance.Type: ApplicationFiled: June 20, 2013Publication date: October 24, 2013Inventors: Christian Rye Iversen, Marcus Granger-Jones
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Patent number: 8547157Abstract: Embodiments provide a radio frequency (RF) switching apparatus including an RF switching device configured to receive an RF input signal and to pass an RF output signal if the RF switching device is activated. The RF switching apparatus may include a control terminal to receive a control signal to activate the RF switching device. A gate resistor may be coupled between the control terminal and a gate terminal of the RF switching device. A helper circuit may be coupled in parallel with the gate resistor. The helper circuit may be configured to provide a temporary conductive path between the control terminal and the gate terminal in response to a state transition of the control signal. The helper circuit may provide an open circuit between the control terminal and the gate terminal during a steady state of the control signal between state transitions.Type: GrantFiled: April 25, 2012Date of Patent: October 1, 2013Assignee: TriQuint Semiconductor, Inc.Inventors: Tobias Mangold, Andreas Weisgerber
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Patent number: 8547156Abstract: Apparatus and methods are disclosed related to using one or more field effect transistors as a resistor. One such apparatus can include a field effect transistor (FET), averaging resistors and a bidirectional current source. The averaging resistors can apply an average of a voltage at the source of the FET and a voltage at the drain of the FET to the gate of the field effect transistor. The bidirectional current source can turn the FET on and off. The FET can operate in the ohmic region when on. Such an apparatus can improve the linearity of the FET as a resistor, for example, at lower frequencies near or at direct current (DC). In some implementations, the apparatus can include one or more current sources to remove an offset introduced by the bidirectional current source at the source and/or the drain of the FET.Type: GrantFiled: January 25, 2012Date of Patent: October 1, 2013Assignee: Analog Devices, Inc.Inventor: Omid Foroudi
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Publication number: 20130214841Abstract: An attenuation circuit uses a voltage controlled variable resistance transistor as a signal attenuator for receivers operating in the zero Hz to about 30 MHz range. The transistor functions in the linear region to linearize the transistor resistance characteristics used for signal attenuation. In an exemplary application, the attenuation circuit is used as an RF attenuator for AM radio broadcast receivers and amplifiers with automatic gain control. Multiple attenuation circuits can be coupled in parallel, each attenuation circuit having a different sized variable resistance transistor, to form sequentially activated stages that increase the range of attenuation while minimizing distortion.Type: ApplicationFiled: February 13, 2013Publication date: August 22, 2013Applicant: Maxim Integrated Products, Inc.Inventors: Robert G. Meyer, Joel D. Birkeland
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Patent number: 8509682Abstract: A switch element includes a switch device having a drain, a source and a plurality of gates, and at least one additional interconnect located between the plurality of gates, the additional interconnect operative to establish a constant potential between the at least two gates.Type: GrantFiled: April 2, 2012Date of Patent: August 13, 2013Assignee: Skyworks Solutions, Inc.Inventors: Dima Prikhodko, Jerod F. Mason, Steven P. Matte, John Pessia, Jason Chiesa, Sergey Nabokin, Gene A. Tkachenko, Richard A. Carter, Steven C. Sprinkle, Mikhail Shirokov
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Patent number: 8497730Abstract: A circuit includes a passive element having an impedance. An active circuit can be configured to receive an impedance signal associated with the impedance. The impedance includes a real portion and an imaginary portion. The active circuit removes at least a portion of the real portion of the impedance signal. The circuit can be utilized in a wide array of applications including radio applications.Type: GrantFiled: June 9, 2011Date of Patent: July 30, 2013Assignee: Rockwell Collins, Inc.Inventor: Russell D. Wyse
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Publication number: 20130141152Abstract: A voltage controlled variable resistor circuit is configured to variably attenuate a variable source signal. A fixed attenuation circuit is coupled to receive the variable source signal and output an attenuated variable source signal. The variable source signal is further applied across a variable resistive divider formed of a fixed resistive circuit and a variable resistive circuit. The variable resistive circuit has a first input configured to receive the attenuated variable source signal and a second input configured to receive a variable resistance control signal. The variable resistive circuit is configured to have a resistance which is variable in response to the attenuated variable source signal and the variable resistance control signal.Type: ApplicationFiled: November 16, 2012Publication date: June 6, 2013Applicant: STMICROELECTRONICS (SHENZHEN) R&D CO. LTD.Inventor: STMICROELECTRONICS (SHENZHEN) R&D CO. LTD.
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Patent number: 8457246Abstract: An apparatus and method for amplifying a Transmit (Tx) signal according to an Envelope Tacking (ET) scheme in a wireless communication system are provided. A transmitting end apparatus includes an envelope gain controller for controlling a gain of a digital baseband Tx signal in accordance with power control, a detector for detecting an envelope signal from the digital baseband Tx signal whose gain is controlled, and for shaping on the envelope signal, a first Digital to Analog Converter (DAC) for converting the shaped envelope signal into an analog signal, and an envelope modulator for generating a drain bias of a power amplifier that amplifies a Radio Frequency (RF) Tx signal by using the analog envelope signal. Accordingly, a digital-based ET scheme is implemented, and by using a plurality of shaping tables, efficiency of the ET scheme can be maximized in a transmitting end that uses power control.Type: GrantFiled: September 7, 2010Date of Patent: June 4, 2013Assignee: Samsung Electronics Co., LtdInventors: Shin-Ho Kim, Hyung-Weon Park
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Patent number: 8451044Abstract: A method for controlling a switch based on transistors is disclosed. A switching circuit for switching a signal from an input port to an output port thereof is provided. A shunting circuit for switchably shunting the signal from the input port to ground is also provided. A control signal is generated for biasing a control port of the shunting circuit and an approximately complementary control signal is generated for biasing of the switching circuit to either shunt a signal received at the input port or to switch the signal to the output port. A further bias signal for biasing a port within the switching circuit along the signal path between the input port and the output.Type: GrantFiled: June 29, 2009Date of Patent: May 28, 2013Assignee: SiGe Semiconductor, Inc.Inventors: John Nisbet, Michael McPartlin, Chun-Wen Paul Huang
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Publication number: 20130127513Abstract: In one embodiment, a temperature compensating attenuator is disclosed having an attenuation circuit and a control circuit. The temperature compensating attenuator circuit may include a first series connected attenuation circuit segment and a shunt connected attenuation circuit segment, as well as additional attenuation circuit segments. Each attenuation circuit segment includes a stack of transistors that are coupled to provide the attenuation circuit segment with an impedance attenuation level having a continuous impedance range. The control circuit may be operably associated with the stack of transistors in each attenuation circuit segment to control the attenuation level of the attenuation circuit. The temperature compensating attenuator includes a temperature compensating circuit that compensates for variations in operation of the attenuation circuit due to a temperature change.Type: ApplicationFiled: January 23, 2013Publication date: May 23, 2013Applicant: RF MICRO DEVICES, INC.Inventor: RF Micro Devices, Inc.
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Patent number: 8441297Abstract: Provided is a PMOS resistor. The PMOS resistor includes a PMOS transistor pair, a switching unit, and a negative feedback unit. The PMOS transistor pair is symmetrically connected between first and second nodes. The switching unit compares a voltage of the first node and a voltage of the second node to output one of the voltages of the first and second nodes. The negative feedback unit receives an output of the switching unit to control a current which flows in the PMOS transistor pair, for maintaining a constant resistance value.Type: GrantFiled: December 21, 2011Date of Patent: May 14, 2013Assignee: Electronics and Telecommunications Research InstituteInventors: Seunghyun Jang, Jae Ho Jung
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Publication number: 20130099845Abstract: A circuit and method are provided for switching in a semiconductor based high power switch. Complementary p-type based transistors are utilized along insertion loss insensitive paths allowing biasing voltages to alternate between supply and ground, allowing for negative voltage supplies and blocking capacitors to be dispensed with, while improving performance.Type: ApplicationFiled: December 10, 2012Publication date: April 25, 2013Applicant: SIGE SEMICONDUCTOR INC.Inventor: SiGe Semiconductor Inc.
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Publication number: 20130090077Abstract: A system, such as a transceiver, for controlling an adjustable power level includes first and second power detectors, a network of attenuators, a compensator, a comparator, and a controller. The first power detector measures the power of a signal. The network of attenuators receives the signal and generates an attenuated signal. The compensator receives the attenuated signal and generates a compensated signal. The second power detector measures the power of the compensated signal. The comparator receives the respective outputs from the first and second power detectors and generates a first error signal. The controller enables the fixed attenuation, correspondingly adjusts the variable attenuation, receives a second error signal, and provides a control signal to the network of attenuators to nullify an attenuation mismatch introduced between the fixed attenuation and the variable attenuation. A corresponding method for controlling an adjustable power level is also disclosed.Type: ApplicationFiled: September 27, 2012Publication date: April 11, 2013Applicant: SKYWORKS SOLUTIONS, INC.Inventor: Skyworks Solutions, Inc.
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Patent number: 8416012Abstract: A reference voltage generating circuit includes a first power supply, a second power supply, a first variable resistance circuit having one end connected to the first power supply and configured to be capable of adjusting a resistance value of the first variable resistance circuit, a series resistance circuit having at least one resistance and one end connected to the first variable resistance circuit, a second variable resistance circuit having one end connected to the series resistance circuit and the other end connected to the second power supply, and configured to be capable of adjusting a resistance value of the second variable resistance circuit, a first terminal arranged between the first variable resistance circuit and the series resistance circuit, a second terminal arranged between the series resistance circuit and the second variable resistance circuit, and a voltage selecting circuit configured to select one of a voltage of the first terminal and a voltage of the second terminal, and output the seType: GrantFiled: January 18, 2011Date of Patent: April 9, 2013Assignee: Ricoh Company, Ltd.Inventor: Keiichi Ashida
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Patent number: 8400205Abstract: Apparatus and methods are disclosed related to using one or more field effect transistors as a resistor. One such apparatus includes a field effect transistor with a first series circuit in parallel with the gate and the source of the field effect transistor and a second series circuit in parallel with the gate and the drain of the field effect transistor. Each series circuit can include a capacitor and a switch in series with the capacitor. The switch can be configured to be on when the field effect transistor is on, and to be off when the field effect transistor is off. This can improve the linearity of the field effect transistor as a resistor. In some implementations, the apparatus can further include an isolation resistor having a first end and a second end, the first end electrically coupled to the gate of the field effect transistor.Type: GrantFiled: April 8, 2011Date of Patent: March 19, 2013Assignee: Analog Devices, Inc.Inventor: Omid Foroudi
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Patent number: 8390359Abstract: An attenuation circuit uses a voltage controlled variable resistance transistor as a signal attenuator for receivers operating in the zero Hz to about 30 MHz range. The transistor functions in the linear region to linearize the transistor resistance characteristics used for signal attenuation. In an exemplary application, the attenuation circuit is used as an RF attenuator for AM radio broadcast receivers and amplifiers with automatic gain control. Multiple attenuation circuits can be coupled in parallel, each attenuation circuit having a different sized variable resistance transistor, to form sequentially activated stages that increase the range of attenuation while minimizing distortion.Type: GrantFiled: April 30, 2010Date of Patent: March 5, 2013Assignee: Maxim Integrated Products, Inc.Inventors: Robert G Meyer, Joel D Birkeland
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Patent number: 8390395Abstract: In an improved T/R switch configuration of a radio transceiver, the sizes of active switches coupled in series between the receive port and the common port are tapered such that the voltage referenced to ground across the active devices of the T/R switch is more evenly distributed among the switches which increases the power handling capability of that path. According to one embodiment of the present invention, an RF switch includes a plurality of first switches coupled in series between a transmit port and a common port for transmitting an RF signal, and a plurality of second switches coupled in series between a receive port and the common port. At least two of the plurality of second switches have different sizes such that the at least two of the second switches have substantially the same nodal impedance with respect to a frequency of the RF signal and an RF ground.Type: GrantFiled: May 3, 2010Date of Patent: March 5, 2013Assignee: Raytheon CompanyInventors: James M. Carroll, John R. Stanton, John G. Heston
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Patent number: 8368451Abstract: A radio frequency (RF) switch circuit includes switching devices coupled at a common node and a floating control signal circuit (CSS) coupled to the control electrodes of the switching devices and the common node and configured to isolate RF signals from the CSS and configured to provide differential voltage signals to the common node and each of the control electrodes.Type: GrantFiled: March 31, 2011Date of Patent: February 5, 2013Assignee: Auriga Measurement Systems, LLCInventors: Steven A. Mulawski, Yusuke Tajima
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Patent number: 8362850Abstract: A circuit includes a first node, a second node, a third node between the first and second nodes, a first field effect transistor coupled between the first and third nodes, a second field effect transistor coupled to the third node including a second gate terminal coupled to a second resistor, a third field effect transistor coupled to the third node including a third gate terminal coupled to a third resistor, a first capacitor coupled to the second field effect transistor, a second capacitor coupled to the third field effect transistor, a third capacitor coupled between the second and third nodes, and a fourth field effect transistor coupled between the second and third nodes.Type: GrantFiled: August 13, 2012Date of Patent: January 29, 2013Assignee: Renesas Electronics CorporationInventor: Junjirou Yamakawa
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Patent number: 8344784Abstract: A method and circuit arrangement is provided for controlling switching transistors of an integrated circuit, with a bridge circuit and with a control unit, which is designed and/or has a program so that the control unit is designed as a measuring device and measures a bridge voltage of the bridge circuit, outputs an adjusting signal for adjusting a component of a bridge circuit, and outputs a control signal for activating the switching transistors. When the bridge circuit) has a branch with a resistor network and a transistor connected in series, and the control unit is designed and/or has a program so that the adjusting signal for adjusting a resistance value of the resistor network is switchable as the component dependent on the bridge voltage.Type: GrantFiled: December 6, 2010Date of Patent: January 1, 2013Assignee: Micronas GmbHInventors: Martin Czech, Ulrich Theus
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Publication number: 20120319755Abstract: An apparatus comprising one or more series transistor network elements and a plurality of shunt circuits. The series transistor network may be configured to generate an output signal in response to (i) an input signal, (ii) a first bias signal, and (iii) a plurality of variable impedances. The plurality of shunt circuits may each be configured to generate a respective one of the variable impedances in response to a second bias signal. The output signal may have an attenuation that is equal to or less than the input power. The amount of the attenuation may be controlled by the first bias signal and the second bias signal. The series transistor elements and the plurality of shunt circuits may be configured as two or more transistors each having two or more gates.Type: ApplicationFiled: June 16, 2011Publication date: December 20, 2012Inventor: Wen Hui Zhang
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Patent number: 8334718Abstract: In one embodiment, a variable attenuator is disclosed having an attenuation circuit and a control circuit. The attenuation circuit may include a first series connected attenuation circuit segment and a shunt connected attenuation circuit segment, as well as additional attenuation circuit segments. Each attenuation circuit segment includes a stack of transistors that are coupled to provide the attenuation circuit segment with a variable impedance level having a continuous impedance range. In this manner, the control circuit may be operably associated with the stack of transistors in each attenuation circuit segment to control the variable attenuation level of the variable attenuator.Type: GrantFiled: December 23, 2010Date of Patent: December 18, 2012Assignee: RF Micro Devices, Inc.Inventors: Marcus Granger-Jones, Brad Nelson, Ed Franzwa
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Patent number: 8330519Abstract: A circuit and method are provided for switching in a semiconductor based high power switch. Complementary p-type based transistors are utilized along insertion loss insensitive paths allowing biasing voltages to alternate between supply and ground, allowing for negative voltage supplies and blocking capacitors to be dispensed with, while improving performance.Type: GrantFiled: July 9, 2010Date of Patent: December 11, 2012Assignee: SiGe Semiconductor Inc.Inventors: Lui (Ray) Lam, Hanching Fuh
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Patent number: 8326235Abstract: There is provided a communication device including: a first node connected to an antenna; a transmission unit outputting a signal to the antenna via the first node; a reception unit having a signal input thereto from the antenna via the first node; a first switch provided between the first node and the transmission unit; and a second switch provided between the first node and the reception unit, and in which the second switch is alternately turned on and off repeatedly, and the reception unit includes an amplifier amplifying a signal that the transmission unit outputs via the first and second switches and a mixer mixing a signal amplified in the amplifier and a local signal.Type: GrantFiled: July 16, 2010Date of Patent: December 4, 2012Assignee: Fujitsu LimitedInventor: Masaru Sato
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Patent number: 8311502Abstract: A communication device includes a transmission signal processing unit, a driver amplifier coupled to the transmission signal processing unit, a selector coupled to the driver amplifier, a first attenuator coupled to the selector and an output portion of the communication device, a second attenuator coupled to the selector and the output portion of the communication device, and a controller coupled to the selector and the driver amplifier to switch between the first attenuator and the second attenuator based on a notification signal.Type: GrantFiled: January 27, 2012Date of Patent: November 13, 2012Assignee: Renesas Electronics CorporationInventor: Junjirou Yamakawa
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Publication number: 20120280738Abstract: In one embodiment, a variable attenuator is disclosed having an attenuation circuit and a control circuit. The attenuation circuit may include a first series connected attenuation circuit segment and a shunt connected attenuation circuit segment, as well as additional attenuation circuit segments. Each attenuation circuit segment includes a stack of transistors that are coupled to provide the attenuation circuit segment with a variable impedance level having a continuous impedance range. In this manner, the control circuit may be operably associated with the stack of transistors in each attenuation circuit segment to control the variable attenuation level of the variable attenuator.Type: ApplicationFiled: July 13, 2012Publication date: November 8, 2012Applicant: RF MICRO DEVICES, INC.Inventors: Marcus Granger-Jones, Brad Nelson, Ed Franzwa
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Patent number: 8299870Abstract: A programmable gain attenuator (PGA) configured to receive a signal at an input and provide an attenuated version of the signal at an output is provided herein. The PGA includes a resistor coupled between a first tap and a second tap, where the first tap is coupled to the input of the PGA. The PGA further includes two sets of switches. The first set of switches is coupled in parallel between the first tap and the output, and the second set of switches is coupled in parallel between the second tap and the output. The attenuation setting of the programmable gain attenuator can be determined by controlling each set of switches.Type: GrantFiled: January 19, 2010Date of Patent: October 30, 2012Assignee: Broadcom CorporationInventors: Tao Wu, Ramon Gomez
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Patent number: 8299835Abstract: A switch circuit is provided that includes at least one main switching device and at least one shunt switching device. Each main switching device is connected in series with a conductor that carries an RF signal between an input circuit and an output circuit. Each shunt switching device is connected between a controlling terminal of the main switching device and a high frequency ground. The switch circuit can provide substantially improved OFF state isolation over other approaches.Type: GrantFiled: February 2, 2009Date of Patent: October 30, 2012Assignee: Sensor Electronic Technology, Inc.Inventors: Alexei Koudymov, Grigory Simin, Michael Shur, Remis Gaska
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Publication number: 20120256674Abstract: Apparatus and methods are disclosed related to using one or more field effect transistors as a resistor. One such apparatus includes a field effect transistor with a first series circuit in parallel with the gate and the source of the field effect transistor and a second series circuit in parallel with the gate and the drain of the field effect transistor. Each series circuit can include a capacitor and a switch in series with the capacitor. The switch can be configured to be on when the field effect transistor is on, and to be off when the field effect transistor is off. This can improve the linearity of the field effect transistor as a resistor. In some implementations, the apparatus can further include an isolation resistor having a first end and a second end, the first end electrically coupled to the gate of the field effect transistor.Type: ApplicationFiled: April 8, 2011Publication date: October 11, 2012Applicant: Analog Devices, Inc.Inventor: Omid Foroudi
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Publication number: 20120249209Abstract: Provided is a transmission system capable of improving the SN ratio for noise superimposed on a transmission line and extending the dynamic range. The transmission system transmits a signal between a transmitter (1) and a receiver (3), which are connected to each other via a transmission line (2). The transmitter (1) includes a transmission amplifier (11) for stepping up an amplitude of an input signal.Type: ApplicationFiled: December 17, 2009Publication date: October 4, 2012Applicant: Mitsubishi Electric CorporationInventors: Yoshihiro Akeboshi, Hideyuki Ohashi, Tetsuro Komura
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Publication number: 20120212277Abstract: Embodiments of the invention described herein provide a magnetic sensor interface capable of adjusting signal conditioning dynamically using a speed signal of a target such that the true positive and negative peaks of the input signal are maintained for the given target across its entire speed range (0-Max rpm), therefore increasing the signal to noise ratio at low speeds and avoiding clipping or distortion at high speeds. In one aspect, a method comprises receiving an alternating differential voltage signal from a sensor. The differential voltage signal has an amplitude that changes relative to a change in speed of a target. The alternating differential voltage signal is converted to an attenuated single-ended voltage signal that can be dynamically scaled. The attenuated single-ended voltage signal can be scaled by multiplying the attenuated single-ended voltage signal by a scaling factor.Type: ApplicationFiled: February 23, 2011Publication date: August 23, 2012Inventors: James Merrill Roylance, Daniel Zahi Abawi, Biplab Deb
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Patent number: 8232827Abstract: A semiconductor switch includes: a first terminal; a second terminal; a switch section including a through FET connected between the first terminal and the second terminal and a shunt FET connected between the second terminal and a first ground terminal; a first control terminal configured to drive the through FET; a second control terminal configured to drive the shunt FET; and a driver provided on a substrate together with the switch section and configured to provide a differential output to the first control terminal and the second control terminal.Type: GrantFiled: March 18, 2010Date of Patent: July 31, 2012Assignee: Kabushiki Kaisha ToshibaInventors: Yoshitomo Sagae, Toshiki Seshita
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Publication number: 20120161843Abstract: An attenuation control device is provided in a receiver of a high-frequency signal and attenuates the high-frequency signal. The attenuation control device includes a computing unit to output digital data for controlling an amount of attenuation of the high-frequency signal, and a DA converter to perform DA conversion of the digital data into a control current which controls a current which is passed through a PIN diode for attenuating the high-frequency signal, wherein the DA converter outputs an analog current as the control current, which is corrected so that a logarithmic value of the amount of attenuation of the high-frequency signal is allowed to change substantially linearly to the digital data.Type: ApplicationFiled: August 27, 2010Publication date: June 28, 2012Applicant: Mitsumi Electric Co., Ltd.Inventor: Kiminori Yashima
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Patent number: 8207783Abstract: An integrated circuit includes a sensing circuit, a fuse box, and a fuse bus decoder. The sensing circuit includes an output node, and the fuse box includes a plurality of switches coupled in series with a plurality of resistive elements. The fuse box is coupled to the output node of the sensing circuit from which the fuse box is configured to receive a current. The fuse bus decoder is coupled to the fuse box and includes at least one demultiplexer configured to receive a signal and in response output a plurality of control signals for selectively opening and closing the switches of the fuse box to adjust a resistance across the fuse box. A voltage of the output node of the sense amplifier is based on a resistance the fuse box and the current.Type: GrantFiled: August 16, 2010Date of Patent: June 26, 2012Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.Inventors: Wei-Li Liao, Sung-Chieh Lin, Kuoyuan Hsu
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Patent number: 8203397Abstract: An attenuator includes a first terminal, a second terminal, a first circuit coupled between the first and second terminals and including a field effect transistor including a gate terminal coupled to a resistor, a second circuit coupled between the first circuit and the second terminal and coupled to the first circuit via a node, and a third circuit coupled to the node.Type: GrantFiled: July 18, 2011Date of Patent: June 19, 2012Assignee: Renesas Electronics CorporationInventor: Junjirou Yamakawa
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Patent number: 8198932Abstract: A circuit includes a digital-to-analog converter (DAC), coupled to a power supply, that provides a first current at a first output terminal of the DAC and a second current at a second output terminal of the DAC, the first current being differential to the second current; a first circuit, coupled to the first output terminal of the DAC and to the second output terminal of the DAC, that generates a first voltage and a second voltage, the first voltage being non-linear with respect to the first current and the second voltage being non-linear with respect to the second current; and an attenuator coupled to the first circuit, and responsive to the first voltage and the second voltage to attenuate an input signal of the attenuator and to generate linear attenuation characteristics in decibels with respect to the first current and the second current.Type: GrantFiled: May 6, 2010Date of Patent: June 12, 2012Assignee: Texas Instruments IncorporatedInventor: Samala Sreekiran
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Publication number: 20120139633Abstract: A presented semiconductor integrated circuit, which processes an RF signal, achieves preferable distortion characteristics even at the low supply voltage. It includes an attenuator configured to attenuate an input signal with a variable attenuation, a source follower configured to receive an output of the attenuator, and an amplifying unit configured to perform a filtering process on an output of the source follower, and then amplify the output of the source follower with a variable gain.Type: ApplicationFiled: February 16, 2012Publication date: June 7, 2012Applicant: Panasonic CorporationInventors: Takafumi Nasu, George Hayashi, Katsumasa Hijikata
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Patent number: 8179205Abstract: Systems and methods for provided for linearization systems and methods for variable attenuators. The variable attenuators can include series transistors along a main signal path from the input to output, as well as shunt transistors. A bootstrapping body bias circuit can be used with one or of the series transistors to allow the body of a connected transistor to swing responsive to a received RF input signal. As the RF signal increases and affects the gate-to-source voltage difference of a transistor, a bootstrapping body bias circuit can adaptively adjust the threshold voltage of the connected transistor and compensate the channel resistance variation resulting from gate-to-source voltage swing. The bootstrapping body bias circuit can be implemented using passive elements, active elements, or a combination thereof.Type: GrantFiled: May 21, 2010Date of Patent: May 15, 2012Assignee: Samsung Electro-MechanicsInventors: Yanyu Huang, Wangmyong Woo, Chang-Ho Lee, Joy Laskar
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Patent number: 8154332Abstract: A current-controlled resistor comprises a first input terminal configured to receive an input signal and a second input terminal configured to receive a current control signal. The resistor comprises a first stage configured to receive the current control signal; the first stage includes first and second PN diodes having first terminals of a first type and second terminals of a second type. The first terminals of the first and second PN diodes are coupled each other and a second terminal of the first PN diode is coupled to the first input terminal. The resistor comprises a second stage configured to receive the current control signal; the second stage includes a third PN diode having first and second terminals of the first and second types, the second terminal of the third PN diode being coupled to the second terminal of the second PN diode.Type: GrantFiled: October 30, 2009Date of Patent: April 10, 2012Assignee: STMicroelectronics Design and Application GmbHInventor: Sebastian Zeller
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Patent number: 8149042Abstract: An analog signal is input to an input terminal. An analog signal is output via an output terminal. A first transistor is an N-channel MOSFET, and is provided between the input terminal and the output terminal. A first resistor is provided between the gate of the first transistor and a first fixed voltage terminal (power supply terminal), which sets the gate of the first transistor to a high-impedance state.Type: GrantFiled: September 20, 2011Date of Patent: April 3, 2012Assignee: Rohm Co., Ltd.Inventors: Hironori Nakahara, Sachito Horiuchi
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Patent number: 8135369Abstract: The attenuation characteristics of an attenuator largely changes depending on the frequency of an input signal. Accordingly, a difference between the amounts of attenuation of gains of each two attenuators included in a communication device is not constant. In communications using the wireless USB, the difference needs to be in a range of 2 dB±1 dB. Thus, the communication device does not meet the standards of the wireless USB unless the difference between the amounts of attenuation of the attenuators is adjusted. In this regard, provided is a communication device including first and second attenuators that attenuate a signal. The second attenuator is provided with a regulator circuit that adjusts a relation between an amount of attenuation of the signal through the first attenuator and an amount of attenuation of the signal through the second attenuator.Type: GrantFiled: November 4, 2008Date of Patent: March 13, 2012Assignee: Renesas Electronics CorporationInventor: Junjirou Yamakawa
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Patent number: RE43266Abstract: An attenuator includes a housing defining an interior, a front, a rear, and a rotor mounted between front and rear for rotation within housing about an axis of the rotor. First electrical contacts are provided on the housing. Second electrical contacts are provided on the rotor. The rotor includes multiple printed conductor boards. Each PC board includes an electrically relatively non-conductive substrate. One side of each substrate provides conductive areas through which electrically attenuating elements of the attenuator are coupled together to form an attenuating network providing a selected level of attenuation. Electrical contact is made between the first electrical contacts and the electrically attenuating elements of the attenuator through the second electrical contacts.Type: GrantFiled: November 20, 2001Date of Patent: March 27, 2012Assignee: Trilithic, Inc.Inventors: Bruce G. Malcolm, Michael G. Pazoga, Steven L. Sink