Abstract: In some aspects, the disclosure is directed to methods and systems for common-mode ripple correction for high-speed transmitters. In one or more embodiments, the system includes a driver circuit of a complementary metal-oxide semiconductor (CMOS) transmitter. In one or more embodiments, the driver circuit has an output common-mode. In one or more embodiments, the system includes a predriver circuit with an output in electrical communication with an input of the driver circuit. In one or more embodiments, a comparator generates a control signal using a difference between an average signal value of the output common-mode and a target value. In one or more embodiments, the comparator block generates signals which can be used to adjust the strength of at least one of a pull-up path or a pull-down path in the predriver circuit.

Abstract: A programmable frequency receiver includes a slicer for receiving data at a first frequency, a de-multiplexer for de-multiplexing the data at a second frequency, a programmable clock generator for generating a clock at the first frequency, and first and second resonant clock amplifiers for amplifying clock signals at the first and second frequencies. The resonant clock amplifiers include an inductor having a low Q value, allowing them to amplify clock signals over the programmable frequency range of the receiver. The second resonant clock amplifier includes digitally tunable delay elements to delay and center the amplified clock signal of the second frequency in the data window at the interface between the slicer and the de-multiplexer. The delay elements can be capacitors. A calibration circuit adjusts capacitive elements within a master clock generator to generate a master clock at the first frequency.

Abstract: Improved master latch for high-speed slicer providing enhanced input signal sensitivity. A pre-charging circuit injects charge into the sources of the differential pair of a latch that samples the input signal during odd clock cycles. This reduces the gate-to-source voltage of the sampling pair, making them less sensitive to data bits latched by a second parallel master latch in odd clock cycles. The injected charge dissipates before the sampling pair is needed to fully sample the input signal in even clock cycles. The pre-charging circuit includes a current mirror, a current source and a transistor that couples the current source to the current mirror during odd clock cycles. A shunt peaked amplifier with excess peaking boosts the high-frequency content of a differential input signal relative to its low-frequency content. Capacitors cross-couple the gates and drains of the differential sampling pair.

Abstract: A programmable frequency receiver includes a slicer for receiving data at a first frequency, a de-multiplexer for de-multiplexing the data at a second frequency, a programmable clock generator for generating a clock at the first frequency, and first and second resonant clock amplifiers for amplifying clock signals at the first and second frequencies. The resonant clock amplifiers include an inductor having a low Q value, allowing them to amplify clock signals over the programmable frequency range of the receiver. The second resonant clock amplifier includes digitally tunable delay elements to delay and center the amplified clock signal of the second frequency in the data window at the interface between the slicer and the de-multiplexer. The delay elements can be capacitors. A calibration circuit adjusts capacitive elements within a master clock generator to generate a master clock at the first frequency.

Abstract: According to one general aspect, a distributed threshold adjuster (DTA) may be interspersed between stages of a multistage amplifier to adjust the DC voltage of an input signal. The DTA may include an input signal terminal configured to receive the input signal. The DTA may also include a plurality of current sources configured to produce an adjustment current signal whose amperage is configured to be increased or decreased by fixed steps in order to adjust the DC voltage of the input signal. The DTA may include a control unit configured to selectively turn on or off the individual current sources of the plurality of current sources to select the amperage of the adjustment current signal. The DTA may further include an output terminal configured to produce an output signal, comprising a combination of the input signal and the adjustment current signal, to a stage of a multistage amplifier.

Abstract: A programmable frequency receiver includes a slicer for receiving data at a first frequency, a de-multiplexer for de-multiplexing the data at a second frequency, a programmable clock generator for generating a clock at the first frequency, and first and second resonant clock amplifiers for amplifying clock signals at the first and second frequencies. The resonant clock amplifiers include an inductor having a low Q value, allowing them to amplify clock signals over the programmable frequency range of the receiver. The second resonant clock amplifier includes digitally tunable delay elements to delay and center the amplified clock signal of the second frequency in the data window at the interface between the slicer and the de-multiplexer. The delay elements can be capacitors. A calibration circuit adjusts capacitive elements within a master clock generator to generate a master clock at the first frequency.

Abstract: Embodiments of a summer block for a Decision Feedback Equalizer are provided herein. The summer block is configured to offset a combination of a Feed Forward Equalized (FFE) data signal and a Feedback Equalized (FBE) data signal by a dc amount: The dc amount is based on at least a weight of a tap previously implemented with an FBE of the DFE. The summer block can be further configured to offset the combination of the FFE data signal and the FBE data signal based on a dc offset value necessary to compensate for asymmetries in the data eye of data received by the FFE over a channel and a dc offset value necessary to compensate for mismatches present in the circuits of the DFE.

Abstract: A programmable frequency receiver includes a slicer for receiving data at a first frequency, a de-multiplexer for de-multiplexing the data at a second frequency, a programmable clock generator for generating a clock at the first frequency, and first and second resonant clock amplifiers for amplifying clock signals at the first and second frequencies. The resonant clock amplifiers include an inductor having a low Q value, allowing them to amplify clock signals over the programmable frequency range of the receiver. The second resonant clock amplifier includes digitally tunable delay elements to delay and center the amplified clock signal of the second frequency in the data window at the interface between the slicer and the de-multiplexer. The delay elements can be capacitors. A calibration circuit adjusts capacitive elements within a master clock generator to generate a master clock at the first frequency.

Abstract: Improved master latch for high-speed slicer providing enhanced input signal sensitivity. A pre-charging circuit injects charge into the sources of the differential pair of a latch that samples the input signal during odd clock cycles. This reduces the gate-to-source voltage of the sampling pair, making them less sensitive to data bits latched by a second parallel master latch in odd clock cycles. The injected charge dissipates before the sampling pair is needed to fully sample the input signal in even clock cycles. The pre-charging circuit includes a current mirror, a current source and a transistor that couples the current source to the current mirror during odd clock cycles. A shunt peaked amplifier with excess peaking boosts the high-frequency content of a differential input signal relative to its low-frequency content. Capacitors cross-couple the gates and drains of the differential sampling pair.

Abstract: Embodiments of a summer block for a Decision Feedback Equalizer are provided herein. The summer block is configured to offset a combination of a Feed Forward Equalized (FFE) data signal and a Feedback Equalized (FBE) data signal by a dc amount. The dc amount is based on at least a weight of a tap previously implemented with an FBE of the DFE. The summer block can be further configured to offset the combination of the FFE data signal and the FBE data signal based on a dc offset value necessary to compensate for asymmetries in the data eye of data received by the FFE over a channel and a dc offset value necessary to compensate for mismatches present in the circuits of the DFE.

Abstract: According to one general aspect, an apparatus may include a terminal configured to receive an analog input signal. In various embodiments, the apparatus may also include a multistage amplifier configured to amplify the analog input signal by an amount of gain. In some embodiments, the apparatus may include a distributed threshold adjuster interspersed between the stages of the multistage amplifier configured to adjust the DC voltage of the analog input signal to facilitate a decision by an analog-to-digital converter (ADC). In one embodiment, the apparatus may include the ADC configured to convert the amplified analog input signal to a digital output signal.

Abstract: According to one general aspect, a distributed threshold adjuster (DTA) may be interspersed between stages of a multistage amplifier to adjust the DC voltage of an input signal. The DTA may include an input signal terminal configured to receive the input signal. The DTA may also include a plurality of current sources configured to produce an adjustment current signal whose amperage is configured to be increased or decreased by fixed steps in order to adjust the DC voltage of the input signal. The DTA may include a control unit configured to selectively turn on or off the individual current sources of the plurality of current sources to select the amperage of the adjustment current signal. The DTA may further include an output terminal configured to produce an output signal, comprising a combination of the input signal and the adjustment current signal, to a stage of a multistage amplifier.

Abstract: According to one general aspect, an output driver configured to drive output signals from a core device may include a voltage convertor, an output stage, and a biasing unit. In various embodiments, the output driver is configured to operate in either a core device voltage mode or a high voltage mode. In some embodiments, the voltage convertor may be configured to receive a pair of differential input signals from a core device, wherein a maximum voltage of the input signals is equivalent to a core device voltage, and convert the input signals to a pair of intermediate input signals. In one embodiment, when in high voltage mode, the maximum voltage of the intermediate input signals may be equivalent to a high voltage that is higher than the core device voltage.

Abstract: According to one general aspect, an apparatus may include a terminal configured to receive an analog input signal. In various embodiments, the apparatus may also include a multistage amplifier configured to amplify the analog input signal by an amount of gain. In some embodiments, the apparatus may include a distributed threshold adjuster interspersed between the stages of the multistage amplifier configured to adjust the DC voltage of the analog input signal to facilitate a decision by an analog-to-digital converter (ADC). In one embodiment, the apparatus may include the ADC configured to convert the amplified analog input signal to a digital output signal.

Abstract: According to one general aspect, an output driver configured to drive output signals from a core device may include a voltage convertor, an output stage, and a biasing unit. In various embodiments, the output driver is configured to operate in either a core device voltage mode or a high voltage mode. In some embodiments, the voltage convertor may be configured to receive a pair of differential input signals from a core device, wherein a maximum voltage of the input signals is equivalent to a core device voltage, and convert the input signals to a pair of intermediate input signals. In one embodiment, when in high voltage mode, the maximum voltage of the intermediate input signals may be equivalent to a high voltage that is higher than the core device voltage.