Abstract: An apparatus, method, and article to dynamically adjust a data signal using a regenerated clock signal in an emulator to increase communication speed between the emulator and the evaluation board is disclosed. In one embodiment, this is achieved by applying a reference clock signal at a predetermined frequency to a digital circuit. A delayed return data signal is then sampled from the digital circuit. The sampled delayed return data signal is then compared to an expected return data signal. The delayed return data signal is then adjusted as a function of the comparison to increase the communication speed between the emulator and the evaluation board.
Type:
Application
Filed:
April 22, 2009
Publication date:
August 13, 2009
Applicant:
ANALOG DEVICES, INC.
Inventors:
David DOYLE, Hossain HAJIMOWLANA, Kevin GAGNE, Joseph BASTOS, Chirag PATEL
Abstract: A measurement signal from a detector may have a complementary polarity. For example, an RF power detector may generate an output signal that decreases in magnitude in response to an increasing input signal. In one embodiment, the RF power detector may include a series of transconductance detector cells arranged to progressively turn off as the input signal becomes progressively larger.
Abstract: A MEMS microphone has an SOI wafer, a backplate formed in a portion of the SOI wafer, and a diaphragm adjacent to and movable relative to the backplate. The backplate has at least one trench that substantially circumscribes a central portion of the backplate.
Type:
Application
Filed:
March 26, 2009
Publication date:
August 13, 2009
Applicant:
ANALOG DEVICES, INC.
Inventors:
Xin Zhang, Thomas Chen, Sushil Bharatan, Aleksey S. Khenkin
Abstract: A method and apparatus for protecting access to sensitive information stored in vulnerable storage areas (e.g., public memory, registers, cache) of a microprocessor. A microprocessor having a reset port to receive external reset commands may have a reset diversion circuit that may be selectively enabled. The microprocessor may operate in an open mode or a secure mode, indicating the absence or the potential presence, respectively, of sensitive information in the vulnerable storage areas. In open mode, the reset diversion circuit may be disabled such that external reset requests triggers a hardware reset. In secure mode, sensitive information may be recorded on vulnerable storage areas. The reset diversion circuit may be enabled to divert external reset requests to an interrupt which may trigger execution of a software code. The software code, when executed, may perform a secured system clean-up routine to erase the vulnerable storage areas prior to reset.
Type:
Application
Filed:
February 4, 2009
Publication date:
August 13, 2009
Applicant:
Analog Devices, Inc.
Inventors:
Philip P. Giordano, Scott D. Biederwolf
Abstract: A voltage level translator provides an output signal having an external voltage in response to an input signal having an internal voltage. The voltage level translator includes first and second input signal transistors, first and second output signal transistors, and includes a signal stabilization circuit and/or an enable circuit. A ready-signal generation circuit provides a ready signal indicating that a voltage supply is at an operating voltage. The ready-signal generation circuit can include unbalanced transistors.
Type:
Grant
Filed:
August 17, 2005
Date of Patent:
August 11, 2009
Assignee:
Analog Devices, Inc.
Inventors:
Brian David Johansson, Stuart Patterson
Abstract: Disclosed are a circuit and a method for tuning a programmable filter including input terminals, output terminals, a filter network and a transadmittance stage. The input terminals can receive input signals, and the output terminals output a filtered signal. The transadmittance stage, coupled to the input terminals, generates a current at its output based on the input signals. The output of the transadmittance stage can be coupled to the output terminals. The filter network can be a resistive-capacitive network connected to the input terminals. The RC network can include a capacitance respectively coupling the input terminals to output terminals, and a voltage divider network coupling the input and output terminals together. The transadmittance stage output terminals can be connected to the voltage divider, and the output terminals of the programmable filter circuit are coupled to respective intermediate nodes of the voltage divider network to provide a filtered output signal.
Abstract: A switched-capacitor circuit includes a plurality of cascaded differential-input, single-ended-output amplifiers. A negative feedback path, from an output terminal of a last of the cascaded amplifiers to an input terminal of a first of the cascaded amplifiers, is configured to exclude, and not be shorted out by, any switches.
Type:
Application
Filed:
August 20, 2008
Publication date:
August 6, 2009
Applicant:
ANALOG DEVICES, INC.
Inventors:
Iliana Fujimori CHEN, Christopher W. MANGELSDORF
Abstract: A multi-channel circuit includes a first-channel circuit configured to receive a digital input and a second-channel output voltage, and to generate a first-channel output voltage as a function of the received digital input and second-channel output voltage.
Type:
Application
Filed:
August 26, 2008
Publication date:
August 6, 2009
Applicant:
ANALOG DEVICES, INC.
Inventors:
Iliana Fujimori CHEN, David Hall WHITNEY
Abstract: An output stage interface circuit for interfacing with a data bus, comprising first and second rails for receiving respectively a high voltage and a low voltage from a power supply; a data output terminal; a first main switch element coupled between said terminal and the first rail and comprising a first main MOS device having a gate and an independently configurable back gate, and responsive to a first data control signal applied to the gate pulling the voltage on the data output terminal toward the first rail voltage; and a first control circuit responsive to the voltage on said terminal being pulled from a first state across a first voltage reference to a second state for coupling said back gate to said terminal and permitting coupling of the gate of said MOS device to said terminal, the first main MOS device presenting a high impedance on the terminal when its voltage is pulled to the second state.
Type:
Grant
Filed:
October 27, 2006
Date of Patent:
August 4, 2009
Assignee:
Analog Devices, Inc.
Inventors:
Colm Patrick Ronan, John Twomey, Brian Anthony Moane, Liam Joseph White
Abstract: A common mode rejection calibration scheme for use with a difference amplifier having an associated signal path. A signal is generated which varies with the common mode voltage of the differential input voltage applied to the amplifier. This signal is scaled and coupled into the signal path such that the scaled signal reduces the common-mode error that would otherwise be present in the difference amplifier's output.
Abstract: An output stage, comprising a first transistor operable to pull a voltage at an output node towards a first voltage, and a rechargeable energy store having a potential difference between first and second terminals wherein the rechargeable energy store is arranged to be controllably connected between the output node and a second voltage supply such that the voltage at the output node can be driven to a voltage outside of a range defined between the first and second voltages.
Abstract: An automatic gain control circuit is disclosed. The automatic gain control circuit receives a radio frequency signal at an input. The input passes the radio frequency signal to a first gain loop having a changeable gain. A low pass filter filters the radio frequency signal. In a second gain loop, the gain of the filtered signal is adjusted. The automatic gain control circuit includes at least one signal detector for detecting a signal level in the first gain loop and a signal level in the second gain loop. The automatic gain control circuit also includes an adjustment module for adjusting the gain of the first and second gain loops based upon the detected signal levels wherein overall gain of the first and the second gain loops is increased no greater than a predetermined value.
Abstract: A pseudo-differential active RC integrator is described. The pseudo-differential active RC integrator includes a common-mode feedback sub-circuit to control the common-mode output signal of the integrator. The common-mode feedback subcircuit may be coupled to one or more virtual ground nodes of the pseudo-differential active RC integrator, and may include one or more transconductors.
Abstract: The inputs to an embedded core, e.g., the core terminals, may not be directly connected to pins on the SoC. The lack of direct access to an embedded core's terminals may complicate testing of the embedded core. A test wrapper including boundary scan test (BST) cells may be used to test an embedded core. Dual function BST/ATPG (Automatic Test Pattern Generation) cells may be used to perform both BST and ATPG tests on embedded cores.
Type:
Grant
Filed:
December 21, 2007
Date of Patent:
July 28, 2009
Assignees:
Intel Corporation, Analog Devices, Inc.
Inventors:
Sankaran M. Menon, Luis A. Basto, Tien Dinh, Thomas Tomazin, Juan G. Revilla
Abstract: A method and apparatus for extending the linear range of a phase detector. In one embodiment, a limited range phase difference is generated between selected edges of first and second input signals, and an excursion of the limited range phase difference beyond a predetermined threshold is detected. In response to detecting the excursion of the limited range phase difference beyond a threshold, an edge of the first or second input signal is prevented from influencing subsequent generation of the limited range phase difference, and a compensated phase difference is generated, derived from the limited range phase difference and including a correction component which compensates for the effect of preventing said edge from influencing subsequent generation of the limited range phase difference.
Abstract: A current-mode instrumentation amplifier (IA) error reduction circuit and method employs a current-mode IA topology and an auto-zero circuit. The IA receives a differential voltage (VINP?VINN) and produces differential DC currents (IDC1, IDC2) in response, which are summed to produce the amplifier's output current. Ideally, when VINP=VINN, IDC1 and IDC2 will be equal; however, due to mismatches an error component Ierror will be present such that IDC1=IDC2±Ierror. The auto-zero circuit is employed to reduce the magnitude of Ierror. In operation, in an ‘auto-zero mode’, VINP and VINN are connected together and the auto-zero circuit operates to make IDC1=IDC2; a voltage needed to effect this is stored. Then, in ‘normal mode’, VINP and VINN are disconnected from each other and the IA is placed in the signal path, with the stored voltage acting to keep the magnitude of Ierror low.
Abstract: A ?-type voltage-controlled variable attenuator is disclosed. The variable attenuator may include variably resistive components in the series and shunt arms. The variably resistive components may be implemented as field effect transistors. The shunt arms may be coupled to the series arm, and the variable attenuator may lack capacitors between the series arm and shunt arms. The series arm and shunt arms may display variable resistances which, in combination, operate to provide a variable level of attenuation of an input signal. The variable attenuator may provide any level of attenuation of an input signal over a wide frequency range. The variable attenuator may be implemented as an integrated circuit.
Abstract: A die has a part that is sealed with a cap. The seal can be hermetic or non-hermetic. If hermetic, a layer of glass or metal is formed in the surface of the die, and the cap has a layer of glass or metal at a peripheral area so that, when heated, the layers form a hermetic seal. A non-hermetic seal can be formed by bonding a cap with a patterned adhesive. The cap, which can be silicon or can be a metal paddle, is electrically coupled to a fixed voltage to shield the part of the die.
Abstract: A MEMS microphone has a backplate, a diaphragm movable relative to the backplate, and a backside cavity adjacent to the backplate or the diaphragm. The backside cavity has sidewalls with at least one rib protruding inward toward a center of the backside cavity.
Abstract: A digital signal processor includes a control block configured to issue instructions based on a stored program, and a compute array including two or more compute engines configured such that each of the issued instructions executes in successive compute engines of at least a subset of the compute engines at successive times. The digital signal processor may be utilized with a control processor or as a stand-alone processor. The compute array may be configured such that each of the issued instructions flows through successive compute engines of at least a subset of the compute engines at successive times.