Abstract: Apparatus and methods for pipelined analog-to-digital conversion are disclosed. In some embodiments, a pipeline analog-to-digital converter includes a plurality of multiplying digital-to-analog converter (MDAC) stages coupled in cascade. At least one of the MDAC stages includes two or more flash ADCs connected in parallel, operating alternately to generate digital signals from an analog input voltage. In one embodiment, the flash ADCs provide the digital signals in an alternating manner to a capacitor block that receives a delayed analog input voltage. In another embodiment, the at least one MDAC may include two or more capacitor blocks, each of which is associated with a respective one of the flash ADCs, forming two or more sets of a flash ADC and a capacitor block. In yet another embodiment, the at least one MDAC also include three or more capacitor blocks, each of which can be randomly selected for one of the flash ADCs.
Type:
Application
Filed:
October 13, 2009
Publication date:
April 14, 2011
Applicant:
ANALOG DEVICES, INC.
Inventors:
Franklin Murden, Scott G. Bardsley, Peter R. Derounian
Abstract: A PLL-based frequency translator provides a divider augmented with a sigma delta modulator (SDM) in a reference path. The system may include two primary functional blocks—an input PLL with its reference path containing an integer divider coupled with a SDM (a fractional frequency divider), and an output PLL with its feedback path containing an integer divider coupled with a SDM (a fractional frequency multiplier). The combination of an integer divider and an SDM yields a fractional divider that divides by N+F/M, where N is the integer portion of the division and F/M is the fractional portion of the division, with M denoting the fractional modulus. Furthermore, since it is desirable to have programmable division factors, it is beneficial to define N, F and M as integers as this simplifies a programming interface when the frequency translator is manufactured as an integrated circuit.
Abstract: An exemplary negative impedance converting circuit for functioning as a voltage buffer and/or negating the impedance of a connected load. The negative impedance converting circuit includes inputs, outputs, a first transconductance stage and a second transconductance stage. The transconductance gain value of the first transconductance stage is greater than a transconductance gain value of the second transconductance stage. Exemplary embodiments of a reference voltage buffer using the negative impedance converting circuit are also described.
Abstract: A clock frequency divider for odd numbered divide ratios. The divider clocks two counters in parallel from a reference clock to be divided. One counter is loaded with the divide ratio and the other counter is loaded with the divide ratio except for the least significant bit. The second counter will set a latch when its count has elapsed. The first counter will reset the latch when its count has elapsed and will reload the counters. The latch is used for the divided output, but passes through a retiming circuit. The retiming circuit delays the output edge by one reference clock edge when the least significant bit indicates an odd numbered divide ratio.
Abstract: A most significant bits analog to digital converter for determining a first P bits of an N bit analog to digital conversion, the most significant bits analog to digital converter comprising: a digital to analog converter a capacitive attenuator, and a switching arrangement for inhibiting action of the attenuator during sampling and enabling the attenuator during conversion.
Abstract: A computer program for creating a computer program executable on one or more digital signal processors each having a predefined function set. The computer program includes computer code for receiving user input selecting one or more digital signal processors. The computer program also includes computer code for defining one or more audio digital signal processing graphical controls. Each graphical control has an associated interface handler. The computer program also has computer code for associating an algorithm module containing digital processor specific functionality with the one or more audio graphical controls using the interface handler and computer code for linking the one or more audio graphical controls together defining an execution path.
Abstract: A switched capacitor system with output glitch reduction step charges the switched capacitor by switching it to a first voltage level in a first phase, to an intermediate voltage level of a pre-charge node in a pre-charge phase and to the voltage level of the output node of the amplifier stage in a settling phase; the pre-charge node can be implemented at the input of the amplifier stage, the output of a preceding stage or at any other pre-existing suitable node in the amplifier system.
Abstract: A method of transferring charge from a photosensitive array using a plurality of vertical shift registers, each having a plurality of vertical elements including first and last vertical element is disclosed The vertical shift registers are capable of transferring charge in a first direction from the first to the last vertical element The method also includes using at least one horizontal shift register having a plurality of horizontal elements. Each of the horizontal elements is arranged to receive charge transferred from the last vertical element of a respective one of the plurality of vertical shift registers, and shift the charge in a horizontal direction. The method includes operating the horizontal shift register during a plurality of horizontal operating intervals and operating the plurality of vertical shift registers during at least a portion of the plurality of horizontal operating intervals.
Abstract: A method and a device for canceling an offset voltage in an output of a comparator circuit include sampling a set of offset voltages; applying a set of correction voltages equal in magnitude and opposite in polarity to the set of offset voltages, the set of correction voltages being applied to an output generating arrangement of the comparator circuit; and enabling output of the output generating arrangement after the set of correction voltages is applied.
Type:
Grant
Filed:
March 4, 2009
Date of Patent:
April 5, 2011
Assignee:
Analog Devices, Inc.
Inventors:
Stephen Robert Kosic, Eric John Siragusa
Abstract: A logic signal isolator comprising a transformer having a primary winding and a secondary winding; a transmitter circuit which drives said primary winding in response to a received logic signal, such that in response to a first type of edge in the logic signal, a signal of a first predetermined type is supplied to the primary winding and in response to a second type of edge in the logic signal, a signal of a second predetermined type is supplied to said primary winding, the primary winding and the transmitter being referenced to a first ground; and the secondary winding being referenced to a second ground which is galvanically isolated from the first ground and said secondary winding supplying to a receiver circuit signals received in correspondence to the signals provided to the primary winding, the receiver reconstructing the received logic signal from the received signals.
Abstract: A programmable clock booster system including a clock booster circuit including at least one boost capacitor connected between a first node and a second node for sampling an input voltage in a first phase and applying a boosting voltage to said second node during a second phase, and a programmable capacitor circuit connected to said first node for providing a programmable boosted voltage on said first node during said second phase.
Abstract: A MEMS microphone has 1) a backplate with a backplate interior surface and a plurality of through-holes, and 2) a diaphragm spaced from the backplate. The diaphragm is movably coupled with the backplate to form a variable capacitor. At least two of the through-holes have an inner dimensional shape (on the backplate interior surface) with a plurality of convex portions and a plurality of concave portions.
Abstract: A MEMS device has a first member that is movable relative to a second member. At least one of the first member and the second member has exposed silicon carbide with a water contact angle of greater than about 70 degrees.
Type:
Application
Filed:
September 27, 2010
Publication date:
March 31, 2011
Applicant:
ANALOG DEVICES, INC.
Inventors:
Li Chen, Christine H. Tsau, Thomas Kieran Nunan, Kuang L. Yang
Abstract: A dual backplate MEMS microphone system includes a flexible diaphragm sandwiched between two single-crystal silicon backplates. Such a MEMS microphone system may be formed by fabricating each backplate in a separate wafer, and then transferring one backplate from its wafer to the other wafer, to form two separate capacitors with the diaphragm.
Abstract: A method of forming a MEMS microphone forms circuitry and first MEMS microstructure on a first wafer in a first process, and second MEMS microstructure on a second wafer in a second process. The first process is thermally isolated from the second process. The method also layer transfers the second MEMS microstructure onto the first wafer. The first MEMS microstructure and second MEMS microstructure thus form a variable capacitor that communicates with the circuitry on the first wafer.
Abstract: Variable attenuation systems having continuous input steering may be used to implement vector or quadrature modulators and vector multipliers. Discrete implementations of attenuators with continuous input steering may have two outputs which may be cross-connected to provide four-quadrant operation. A symmetrically driven center tap may provide improved zero-point accuracy.
Abstract: Memory embodiments are provided to operate in memory systems which are configured to have a system ground and a system substrate that are biased at different voltages. At least one of these embodiments includes a memory cell and write and read circuits in which the memory cell is coupled to the system substrate and the write and read circuits are coupled to the system ground. The memory cell preferably has a cross-coupled pair of transistors which can be set in first and second states. The write circuit is arranged and level shifted to drive the cross-coupled pair into either selected one of the states and the read circuit is arranged and level shifted to provide a data signal indicative of the selected state.
Abstract: An embodiment of a multi-path, multi-oxide-thickness amplifier circuit includes a first amplifier having at least one thin-oxide output transistor, and a second amplifier having at least one thick-oxide output transistor. The first and second amplifiers are connected in parallel with each other between an input terminal and an output terminal of the amplifier circuit. The thin-oxide output transistor has a gate-oxide layer thickness that is less than a gate-oxide layer thickness of the thick-oxide output transistor.
Abstract: An RF mixer provides extended dynamic range with reduced noise by utilizing degeneration inductors in the RF input section of a doubly balanced mixer. Degeneration inductors are also utilized in a mixer having a class AB input section. A current mirror in the class AB input section is also inductively degenerated for further noise reduction. The input section is biased by an all-NPN bandgap reference cell which is tightly integrated into the input section so as to reduce the power supply voltage required for the reference cell. The mixer can be optimized for wide input voltage ranges or low distortion.
Abstract: A system and method for determining the true electrical characteristics of a device. A codec is configured to measure at least one electrical characteristic of a device connected to a jack and to identify the device based on the measured electrical characteristics. An updateable database is populated with application circuit information and a software routine is responsive to the measured electrical characteristic and configured to adjust the electrical characteristics measured by the codec based on the application circuit information in the database.
Type:
Grant
Filed:
June 10, 2004
Date of Patent:
March 22, 2011
Assignee:
Analog Devices, Inc.
Inventors:
George Stephan, Frederick Loeb, John Howley, Ludgero Leonardo, Stuart Patterson