Freescale Semiconductor,inc.

Sand 9, Inc.

David R LoCascio

Douglas Alan Garrity

Brandt Braswell

Dean A Badillo

Michael McGowan

Patrick Drennan

James F McClellan

Thierry Cassagnes

Mohammad Nlzam U Kablr

Christopher J Cavanagh

A differential current signal circuit is described which includes a voltage to differential current converter circuit that generates a differential pair of current output signals in response to receiving a voltage input signal, where the differential pair of current output signals are linearly proportional to the voltage input signal within a voltage operating range from a minimum operating voltage to a maximum operating voltage. The differential pair of current output signals are linear over a wide range of voltage input signals. A correction circuit is included which eliminates voltage offsets in the voltage operating range due to process and temperature variations. The correction circuit also provides the capability to adjust the minimum operating voltage, and eliminates variations in the minimum operating voltage due to process and temperature variations.

Differential current signal circuit

A double sampled switched capacitor architecture as described herein includes an amplifier having two separate inputs corresponding to two separate amplifier sections. The amplifier uses a first differential transistor pair for the first amplifier section, a second differential transistor pair for the second amplifier section, a first tail current bias arrangement for the first differential transistor pair, and a second tail current bias arrangement for the second differential transistor pair. The tail current bias arrangements are driven by a bias switching architecture that alternately activates one tail current bias arrangement while at least partially deactivating the other tail current bias arrangement. The amplifier and bias switching architecture cooperate to eliminate gain error that would otherwise be caused by a common parasitic capacitance shared by a single amplifier section.

Amplifier circuit for double sampled architectures

The present invention provides a method for tiling an integrated circuit having a critically matched device such as a transistor. The method obtains an advantage of automatically improving metallic density over critically matched devices thus yielding improved CMP. The method may include the steps of: identifying critically matched devices in the integrated circuit; placing metal tiles over the critically matched device; performing a density test around each critically matched device; and if a density test is not satisfied around a critically matched device, placing at least one metal strip over a critically matched device.

Method of tiling analog circuits

A method for placing tiles in an integrated circuit has matched devices that includes the steps of (1) calculating a metal spacing for tiles to be placed adjacent to the matched device in the integrated circuit; (2) calculating a lateral spacing for tiles to be placed adjacent to the matched device in the integrated circuit; (3) placing tiles about the matched device based on the metal spacing and the lateral spacing; (4) performing a density test in an area around the matched device; and (5) if a density test is not satisfied in the area around the matched device, dividing the matched device into at least two subdevices and repeating, with respect to each subdevice, the steps of calculating a metal spacing, calculating a lateral spacing, and placing tiles about each subdevice. The method is further adaptable to various kinds of matched devices including poly resistors, diffused resistors, double-poly capacitors, metal-insulator-metal capacitors, and fringe capacitors.

Method of tiling analog circuits that include resistors and capacitors

A pipelined analog to digital converter ('ADC') as described herein is capable of processing two or more input channels. The analog input voltages from the multiple channels are concurrently sampled (every other clock phase) using isolated input stages. The outputs of the input stages are concurrently sampled (every other clock phase) by a delay/holding and synchronization ('DHS') stage. The DHS stage processes the samples using a double sampling technique, generates residual voltage samples (every clock phase), and generates digital outputs for the multiple channels in an alternating manner. The DHS stage provides equal input loading for the input stages, which enhances the performance of the ADC.

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Chandler, AZ, United States of America

David R LoCascio