Xilinx, Inc.

Patrick J Quinn

John K Jennings

F Erich Goetting

Anthony J Collins

Georgi Ivanov Radulov

Johannes A Hegt

Arthur H M Van Roermund

James Karp

Jan Lodewijk De Jong

Vassili Kireev

Darragh Walsh

Padraig Kelly

Maxim Pribytko

Michael L Hart

An apparatus relating generally to an analog-to-digital converter ('ADC') is disclosed. In such an apparatus, the ADC is configured for successive approximations. The ADC includes a digital-to-analog converter ('DAC'), a comparator, and a control block. The DAC is coupled to receive a reference input signal and coupled to provide an analog output signal. The analog output signal is capacitively coupled to an analog input node through a capacitor. The capacitor is coupled between the DAC and the comparator to provide capacitive coupling therebetween. The comparator is coupled to the analog input node. The comparator is further coupled to provide a comparator output signal to the control block. The control block is configured for successive approximations to provide a digital output signal to a digital output node. The DAC is coupled to the digital output node to receive the digital output signal as a feedback input signal.

Successive approximation analog-to-digital conversion

A circuit includes an amplifier including a differential input stage including a first input terminal and a second input terminal. The circuit further includes a differential input line coupled to the first input terminal and the second input terminal, and shielding at least partially encompassing the differential input line. The shielding is connected to a node of the differential input stage of the amplifier.

Reducing the effect of parasitic mismatch at amplifier inputs

A system for use within an integrated circuit (IC) can include an input differential pair including a positive input node and a negative input node, a current source coupled to the input differential pair, and a current mirror. The current mirror can include at least a first active device and a second active device. The system can include a biasing transistor device having a source terminal coupled to a gate terminal of each of the first and second active devices, a gate terminal coupled to a drain terminal of the second active device, and a drain terminal coupled to a voltage source. The biasing transistor device is complementary to the current mirror.

Current mirror and high-compliance single-stage amplifier

In accordance with some embodiments, a method for high frequency clock distribution in a VLSI system includes splitting an original master clock signal into one or more pairs of lower-frequency sub-clocks for a destination in the VLSI system, distributing each lower-frequency sub-clock of the one or more pairs of lower-frequency sub-clocks to a corresponding channel coupled to the destination, and reconstructing a reference master clock signal at the destination from the one or more pairs of lower-frequency sub-clocks, wherein the reconstructed reference master clock signal replicates the original master clock signal.

Methods and systems for high frequency clock distribution

A capacitor in an integrated circuit ('IC') has a distribution grid formed in a first patterned metal layer of the integrated circuit and a first vertical conductive filament connected to and extending away from the distribution grid along a first direction. A second vertical conductive filament is connected to the distribution grid and extends in the opposite direction. First and second grid plates are formed in the metal layers above and below the first patterned metal layer. The grid plates surround the first and second vertical conductive filaments. The distribution grid, first vertical conductive filament and second vertical conductive filament are connected to and form a portion of a first node of the capacitor and the first grid plate and the second grid plate are connected to and form a portion of a second node of the capacitor.

Integrated capacitor with cabled plates

An offset cancellation circuit can include an amplifier having a negative input, a positive input, and a single-ended output, wherein the positive input is configured to receive a reference voltage. The circuit also can include a capacitor having a first terminal and a second terminal. The first terminal can be coupled to the negative input of the amplifier. The capacitor can be configured to sample the offset voltage of the amplifier. The second terminal of the capacitor can be selectively coupled to the output of the amplifier.

Differential reference interface with low noise offset cancellation

A capacitor in an integrated circuit ('IC') has a first plurality of conductive crosses formed in a layer of the IC electrically connected to and forming a portion of a first node of the capacitor and a second plurality of conductive crosses formed in the metal layer of the IC. The conductive crosses in the second plurality of conductive crosses are electrically connected to and form a portion of a second node of the capacitor and capacitively couple to the first node.

Integrated capacitor with array of crosses

A capacitor in an IC has a first layer of conductive strips extending along a first direction (Z-direction). A first plurality of conductive strips in the first layer forms a portion a first node of the capacitor and alternates with a second plurality of conductive strips forming a portion of a second node of the capacitor. A plate layer adjacent to the first layer has a third plurality of conductive strips forming a portion the first node. Each strip in the third plurality of conductive strips is adjacent to another strip forming a part of the first node. The strips in the plate layer extend along a second direction (X-direction) orthogonal to the first direction. A first via electrically connects a first conductive strip in the first plurality of conductive strips in the first layer to a second conductive strip in the plate layer.

Integrated capacitor with tartan cross section

A capacitor in an integrated circuit ('IC') includes a core capacitor portion having first conductive elements electrically connected to and forming a part of a first node of the capacitor formed in a first layer and second conductive elements electrically connected to and forming a part of a second node of the capacitor formed in the first layer. The first and second conductive elements alternate in the first conductive layer. Third conductive elements electrically connected to and forming a part of the first node are formed in a second layer adjacent to the first layer. The capacitor also includes a shield capacitor portion having fourth conductive elements formed in at least first, second, third, and fourth layers. The shield capacitor portion is electrically connected to and forms a part of the second node of the capacitor and surrounds the first and third conductive elements.

Shielding for integrated capacitors

A capacitor in an integrated circuit ('IC') has a first node conductor formed in a first metal layer of the IC with a first spine extending along a first direction, a first vertical element extending from the first spine along a second direction perpendicular to the first direction. A first capital element extends along the first direction, and a first serif element extends from the capital element. The capacitor also has a second node conductor having a second spine, a second vertical element extending from the second spine toward the first spine, a second capital element, and a second serif element extending from the second capital between the first vertical element and the first serif element.

Integrated capacitor with interlinked lateral fins

An integrated circuit includes a pass gate having an input and an output. An NMOS pass transistor is connected between the input and the output. The drain of the NMOS pass transistor is connected to the input and the source of the NMOS pass transistor is connected to a node between the source of the NMOS transistor and the output of the pass gate. A current clamp is connected between the node and a current sink so as to conduct current to the current sink when the node reaches a threshold value.

Pass gate with improved latchup immunity

A method and apparatus for the calibration of current cells, whereby a current signal from each current cell may be generated by either a thermometer current cell, or a binary current cell. If generated by a binary current cell, then two or more replica binary current cells exist to form a group of binary current cells within two or more binary current cell sets. The current magnitude generated by each replica current cell of each binary current cell group is first calibrated to be substantially equal to each other. Next, the combined current generated by the replica current cell group is calibrated to be substantially equal to a magnitude of a temporary current signal, or a portion thereof. Subsequent less-significant binary current cell groups are similarly calibrated to the temporary current signal through the use of the previously calibrated, more-significant binary current cell groups.

Method and apparatus for calibrating a scaled current electronic circuit

A method and apparatus compensate for process variations in the fabrication of semiconductor devices. A semiconductor device includes a control circuit that measures a performance parameter of the device, and in response thereto selectively biases one or more well regions of the device to compensate for process variations. For some embodiments, if measurement of the performance parameter indicates that the device does not fall within a specified range of operating parameters, the control circuit biases selected well regions to sufficiently alter the operating characteristics of transistors formed therein so that the device falls within the specified range of operating parameters.

Method and apparatus for compensating for process variations

Method and apparatus for a system monitor embedded in a programmable logic device are described. The system monitor includes a dynamic reconfiguration port interface for configuring or reconfiguring the system monitor during operation thereof. The system monitor includes an analog-to-digital converter which is reconfigurable responsive to input via a dynamic reconfiguration port.

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Dublin, Ireland

Patrick J Quinn