Macom Technology Solutions Holdings, Inc.

Naga Rajesh Doppalapudi

Echere Iroaga

Jian Wang

Quazi Ikram

Mahmoud Reza Ahmadi

Saman Jafarlou

Amaaduddin Zoab Quraishi

The present invention facilitates optical modulation skew adjustment. Components of an on chip optical device driver system can cooperatively operate to provide modulated driver signals to drive configuration of optical signals. A serializer is configured to receive parallel data signals and forward corresponding serial data signals. A multiplexing component is configured to selectively output an in-phase component and a quadrature component of the serial data signals, including implementing skew adjustments to aspects of a first output signal and a second output signal. An output stage is configured to output signals that modulate an optical signal, including the first output signal and the second output signal. An on chip skew detector is configured to detect a skew difference between the first output signal and the second output signal. A skew calibration component is configured to direct skew adjustment between the first output signal and the second output signal.

Optical modulation skew adjustment systems and methods

Various aspects provide for error detection and compensation for a multiplexing transmitter. For example, a system can include an error detector circuit and a duty cycle correction circuit. The error detector circuit is configured to measure duty cycle error for a clock associated with a transmitter to generate error detector output based on a clock pattern for output generated by the transmitter in response to a defined bit pattern. The duty cycle correction circuit is configured to adjust the clock associated with the transmitter based on the error detector output. Additionally or alternatively, the error detector circuit is configured to measure quadrature error between an in-phase clock and a quadrature clock in response to the defined bit pattern. Additionally or alternatively, the system can include a quadrature error correction circuit configured to adjust phase shift between the in-phase clock and the quadrature clock based on quadrature error.

Error detection and compensation for a multiplexing transmitter

A system for calibration of a multi-channel transceiver includes a plurality of voltage regulator circuits, wherein each circuit is configured to produce a voltage for circuitry of one channel of a multi-channel transceiver. The system also includes an analog multiplexer circuit configured to selectively route the output of one of the plurality of voltage regulator circuits to a single comparison circuit. The single comparison circuit is configured to compare an output of one of the plurality of voltage regulator circuits to a target reference voltage and produce an error signal representing a difference between the output of one of the plurality of voltage regulators and the target reference voltage. The system further includes a processor configured to accept the error signal and produce a feedback signal for the one of the plurality of voltage regulator circuits. The feedback signal is operable to adjust the voltage to minimize the difference.

System and method for calibration of multi-channel transceivers

A system for transmitting signals via serial links includes a plurality of lanes for combining data onto a transmission media, a skew detector configured to detect skew among two of the plurality of lanes, and a variable delay circuit controlled by the skew detector, configured to delay the start of a clock signal to circuitry of one of the plurality of lanes.

Closed loop lane synchronization for optical modulation

A cable equalizer configured as part of a cable comprising a first stage, a second stage, and a third stage. The first stage comprises a first stage bias current circuit configured to generate a bias current and a pre-emphasis module configured to introduce pre-emphasis into a received signal to counter the effects of signal amplification. Also part of the first stage is a bias voltage circuit configured to provide a bias voltage to the first stage. The second stage comprises a buffer configured impedance match the first stage. The third stage comprises a third stage bias current circuit configured to generate a bias current and a tank equalizer circuit configured to perform frequency specific equalization on a second stage signal. An amplifier is configured to amplify the second stage signal to create an amplified signal, which is output from the cable equalizer by an output driver.

Adaptive cable equalizer

Various aspects provide for a digitally programmable analog duty-cycle correction circuit. For example, a system includes a duty-cycle correction circuit and a duty-cycle distortion detector circuit. The duty-cycle correction circuit adjusts a clock associated with the transmitter. The duty-cycle distortion detector circuit facilitates digital control of a duty-cycle of the clock associated with the duty-cycle correction circuit based on duty-cycle distortion error associated with output of the transmitter.

Digitally programmable analog duty-cycle correction circuit

Various aspects provide for a multiplexer for high-speed serial links. For example, a system can include a first stage data path multiplexer circuit and a second stage data path multiplexer circuit. The first stage data path multiplexer circuit comprises a first inverter circuit to select a first data signal from a set of data signals and a second inverter circuit to select a second data signal from the set of data signals. The first inverter circuit comprises a first set of inverters and a first set of transmission gates. The second inverter circuit comprises a second set of inverters and a second set of transmission gates. The second stage data path multiplexer circuit is configured as a third inverter circuit to select the first data signal or the second data signal as an output data signal. The third inverter circuit comprises a third set of inverters and a third set of transmission gates.

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Santa Clara, CA, United States of America

Naga Rajesh Doppalapudi