Abstract: A sample and hold circuit is provided. The circuit includes a first switch configured to receive an input, a second switch coupled to a second end of the first switch, a first capacitor coupled to the second end of the first switch, a third switch coupled to a second end of the first capacitor, a fourth switch coupled between the second end of the first capacitor and ground, an op-amp having a first input coupled to the second end of the third switch and a second input connected to ground and an output coupled to the second end of the second switch, a fifth switch coupled to a second end of the third switch, a second capacitor coupled between the output of the op-amp and a second end of the fifth switch, and a sixth switch coupled between the second end of the second capacitor and ground.

Abstract: A pipelined analog-to-digital converter is provided that has advantages of both a high input sample rate as well as low power consumption due to having all but the first pipeline stage operate at a frequency that is a fraction of the input sample rate. The first stage of the pipelined ADC has an internal operating frequency that is the full ADC sample rate, and samples the input signal on the same clock edge for each sample. Subsequent pipeline stages have parallel input sampling circuitry that samples provided input signals at a reduced rate. Since the input sampling circuitry operates at a reduced frequency, power consumption is reduced by those stages. Further, by virtue of sampling the input signal on the same clock edge for each sample, frequency response image generation issues associated with ADC architectures that sample the input signal on more than one clock edge are avoided.

Abstract: A pipelined analog-to-digital converter is provided that has advantages of both a high input sample rate as well as low power consumption due to having all but the first pipeline stage operate at a frequency that is a fraction of the input sample rate. The first stage of the pipelined ADC has an internal operating frequency that is the full ADC sample rate, and samples the input signal on the same clock edge for each sample. Subsequent pipeline stages have parallel input sampling circuitry that samples provided input signals at a reduced rate. Since the input sampling circuitry operates at a reduced frequency, power consumption is reduced by those stages. Further, by virtue of sampling the input signal on the same clock edge for each sample, frequency response image generation issues associated with ADC architectures that sample the input signal on more than one clock edge are avoided.

Abstract: Embodiments of apparatus and methods for applying a gain to an input signal are provided. An embodiment of a switched-capacitor gain stage circuit includes an input node, an output node, an operational amplifier, a correlated-double-sampling portion, a correlated-level-shifting portion, and a switching configuration. The operational amplifier has a first amplifier input, a second amplifier input, and an amplifier output. The correlated-double-sampling portion includes a plurality of sampling capacitors arranged in parallel and selectively coupled between the input node and a central node, and an offset storage capacitor including a first terminal coupled to the first amplifier input. The correlated-level-shifting portion includes a correlated-level-shifting capacitor including a first terminal coupled to the output node.

Abstract: Embodiments of switched-capacitor gain stage circuits and methods of their operation are provided. The circuit includes an operational amplifier, parallel sampling capacitors, an offset storage capacitor coupled to an amplifier input, and multiple switches that are configurable to place the gain stage circuit in a sampling state, a gain state, and an output state. In the sampling state, the switches are configured so that a first charge component representing an input signal is stored on the sampling capacitors, and a second charge component representing an amplifier offset voltage is stored on the offset storage capacitor. In the gain state, the switches are configured so that a third charge component representing a finite gain of the amplifier is stored on the offset storage capacitor. In the output state, the switches are configured so that the first, second, and third charge components contribute to an output signal produced at the output node.

Abstract: Embodiments of apparatus and methods for applying a gain to an input signal are provided. An embodiment of a switched-capacitor gain stage circuit includes an input node, an output node, an operational amplifier, a correlated-double-sampling portion, a correlated-level-shifting portion, and a switching configuration. The operational amplifier has a first amplifier input, a second amplifier input, and an amplifier output. The correlated-double-sampling portion includes a plurality of sampling capacitors arranged in parallel and selectively coupled between the input node and a central node, and an offset storage capacitor including a first terminal coupled to the first amplifier input. The correlated-level-shifting portion includes a correlated-level-shifting capacitor including a first terminal coupled to the output node.

Abstract: Embodiments of switched-capacitor gain stage circuits and methods of their operation are provided. The circuit includes an operational amplifier, parallel sampling capacitors, an offset storage capacitor coupled to an amplifier input, and multiple switches that are configurable to place the gain stage circuit in a sampling state, a gain state, and an output state. In the sampling state, the switches are configured so that a first charge component representing an input signal is stored on the sampling capacitors, and a second charge component representing an amplifier offset voltage is stored on the offset storage capacitor. In the gain state, the switches are configured so that a third charge component representing a finite gain of the amplifier is stored on the offset storage capacitor. In the output state, the switches are configured so that the first, second, and third charge components contribute to an output signal produced at the output node.

Abstract: A converter (200) adapted to convert an analog input signal into a digital output signal includes an analog input terminal (205) for receiving the analog input signal, a Redundant Signed Digit (RSD) stage (210) coupled to the analog input terminal, and a digital section (220). The RSD stage is configured to receive the analog input signal at the analog input terminal, produce a first number of bits at a digital output from the analog input signal during a first half of a first clock cycle, provide a residual feedback signal of the analog input signal at the analog input terminal during a second half of the first clock cycle, and produce a second number of bits at the digital output from the residual feedback signal during a first half of a second clock cycle, the second number of bits less than the first number of bits.

Abstract: A converter (200) adapted to convert an analog input signal into a digital output signal includes an analog input terminal (205) for receiving the analog input signal, a Redundant Signed Digit (RSD) stage (210) coupled to the analog input terminal, and a digital section (220). The RSD stage is configured to receive the analog input signal at the analog input terminal, produce a first number of bits at a digital output from the analog input signal during a first half of a first clock cycle, provide a residual feedback signal of the analog input signal at the analog input terminal during a second half of the first clock cycle, and produce a second number of bits at the digital output from the residual feedback signal during a first half of a second clock cycle, the second number of bits less than the first number of bits.

Abstract: A multi-stage non-overlapping clock signal generator as described herein is suitable for use with a pipelined analog-to-digital converter architecture. The clock signal generator generally includes a back end clock generator, a second stage clock generator, and a first stage clock generator coupled in series. The clock signal generator may also include any number of intermediate stage clock generators coupled in series between the back end clock generator and the second stage clock generator. Example implementations of the various clock generator stages are also described herein.

Abstract: An analog-to-digital converter (ADC) device includes an input terminal to receive an analog signal, an analog component, and control logic. The analog component includes an amplifier having an input and an output and a capacitor network coupled to the input and the output of the amplifier. The capacitor network comprises a plurality of capacitors. The control logic is configured to, in a first mode, configure the capacitor network and the amplifier in an amplification configuration to amplify the analog signal by a predetermined gain to generate an amplified analog signal. The control logic further is configured to, in a second mode, configure the capacitor network and the amplifier to generate a series of one or more residue voltages using the amplified analog signal.

Abstract: An analog-to-digital converter (ADC) device includes an input terminal to receive an analog signal, an analog component, and control logic. The analog component includes an amplifier having an input and an output and a capacitor network coupled to the input and the output of the amplifier. The capacitor network comprises a plurality of capacitors. The control logic is configured to, in a first mode, configure the capacitor network and the amplifier in an amplification configuration to amplify the analog signal by a predetermined gain to generate an amplified analog signal. The control logic further is configured to, in a second mode, configure the capacitor network and the amplifier to generate a series of one or more residue voltages using the amplified analog signal.

Abstract: An analog-to-digital converter (ADC) includes a multiplying digital-to-analog converter (MDAC) having a plurality of capacitors and a plurality of capacitor positions. The ADC generates a random number for a conversion cycle. The ADC configures each capacitor of the plurality of capacitors in a corresponding capacitor position of the plurality of capacitor positions based on the random number for the conversion cycle. The ADC converts, for the conversion cycle, a voltage of an analog signal to a digital value based on the capacitor configurations.

Abstract: A converter (200) adapted to convert an analog input signal into a digital output signal includes an analog input terminal (205) for receiving the analog input signal, a Redundant Signed Digit (RSD) stage (210) coupled to the analog input terminal, and a digital section (220). The RSD stage is configured to receive the analog input signal at the analog input terminal, produce a first number of bits at a digital output from the analog input signal during a first half of a first clock cycle, provide a residual feedback signal of the analog input signal at the analog input terminal during a second half of the first clock cycle, and produce a second number of bits at the digital output from the residual feedback signal during a first half of a second clock cycle, the second number of bits less than the first number of bits.

Abstract: A converter (200) adapted to convert an analog input signal into a digital output signal includes an analog input terminal (205) for receiving the analog input signal, a Redundant Signed Digit (RSD) stage (210) coupled to the analog input terminal, and a digital section (220). The RSD stage is configured to receive the analog input signal at the analog input terminal, produce a first number of bits at a digital output from the analog input signal during a first half of a first clock cycle, provide a residual feedback signal of the analog input signal at the analog input terminal during a second half of the first clock cycle, and produce a second number of bits at the digital output from the residual feedback signal during a first half of a second clock cycle, the second number of bits less than the first number of bits.

Abstract: A switched-capacitor gain stage suitable for use with a pipelined analog to digital converter (“ADC”) is capable of processing two or more input channels. The analog input voltages from the multiple channels are concurrently sampled (every other clock phase), and the gain 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 gain stage provides equal input loading for the input stages, which enhances the performance of the ADC.

Abstract: 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.

Abstract: 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.

Abstract: A system and method for converting an analog signal to a digital signal is provided including a first circuit (22) having a signal range and an input for receiving a first signal, and a second circuit (24) having an input receiving the analog signal and a first output coupled to the input of the first circuit. The first circuit (22) includes an amplifier (28). The first circuit (22) samples the first signal and produces the digital signal from the first signal using the amplifier. A second output of the second circuit (24) is coupled to the amplifier (28). The second circuit (24) samples and scales the analog signal via the amplifier (28) to produce the first signal within the signal range and cancels an offset of the first signal. The system and method reduce power consumption and save device area.

Abstract: A system and method for converting an analog signal to a digital signal is provided including a first circuit (22) having a signal range and an input for receiving a first signal, and a second circuit (24) having an input receiving the analog signal and a first output coupled to the input of the first circuit. The first circuit (22) includes an amplifier (28). The first circuit (22) samples the first signal and produces the digital signal from the first signal using the amplifier. A second output of the second circuit (24) is coupled to the amplifier (28). The second circuit (24) samples and scales the analog signal via the amplifier (28) to produce the first signal within the signal range and cancels an offset of the first signal. The system and method reduce power consumption and save device area.