Abstract:
Methods, systems, and apparatuses are described for reducing the latency in a transceiver. A transceiver includes a high latency communication channel and a low latency communication channel that is configured to be a bypass channel for the high latency communication channel. The low latency communication channel may be utilized when implementing the transceiver is used in low latency applications. By bypassing the high latency communication channel, the high latency that is introduced therein (due to the many stages of de-serialization used to reduce the data rate for digital processing) can be avoided. An increase in data rate is realized when the low latency communication channel is used to pass data. A delay-locked loop (DLL) may be used to phase align the transmitter clock of the transceiver with the receiver clock of the transceiver to compensate for a limited tolerance of phase offset between these clocks.
Abstract:
A high-speed clock generator device includes a phase-interpolator (PI) circuit, a smoothing block, and inverter-based low-pass filters. The PI circuit receives a multiple clock signals with different phase angles and generates an output clock signal having a correct phase angle. The smoothing block smooths the clock signals with different phase angles and generates a number of smooth clock signals featuring improved linearity. The inverter-based low-pass filters filter harmonics of the clock signals with different phase angles.
Abstract:
A communication system may include a number of communication channels operating in accordance with one or more communication standards. The channels may generate data clocks from one or more master clock signals. The phase of the data clocks may be aligned using phase detectors for determining respective phase relationships and using phase interpolators for adjusting respective clock phases. The communication system may include communication channels that operate at different data clock frequencies. These systems may divide their respective data clocks in order to achieve a common clock frequency for use in their phase alignment. The phase detectors and associated circuitry may be disabled to save power when not in use.
Abstract:
A phase lock loop with multiple divider paths is presented herein. The phase lock loop can be used to provide a wide range of frequencies. The phase lock loop can also be used as a portion of a clock multiplier unit or a clock data and recovery unit.
Abstract:
According to an example embodiment, a communications receiver may include a variable gain amplifier (VGA) configured to amplify received signals, a VGA controller configured to control the VGA, a plurality of analog to digital converter (ADC) circuits coupled to an output of the VGA, wherein the plurality of ADC circuits are operational when the communications receiver is configured to process signals of a first communications protocol, and wherein only a subset of the ADC circuits are operational when the communications receiver is configured to process signals of a second communications protocol.
Abstract:
Methods and apparatuses are described for a DSP receiver with an analog-to-digital converter (ADC) having high speed, low BER performance with low power and area requirements. Speed is increased for multi-path ADC configurations by resolving a conventional bottleneck. ADC performance is improved by integrating calibration and error detection and correction, such as distributed offset calibration and redundant comparators. Power and area requirements are dramatically reduced by using low BER rectification to nearly halve the number of comparators in a conventional high speed, low BER flash ADC.
Abstract:
An apparatus and method is disclosed to compensate for one or more offsets in a communications signal. A communications receiver may carry out an offset adjustment algorithm to compensate for the one or more offsets. An initial search procedure determines one or more signal metric maps for one or more selected offset adjustment corrections from the one or more offset adjustment corrections. The offset adjustment algorithm determines one or more optimal points for one or more selected offset adjustment correction based upon the one or more signal maps. The adaptive offset algorithm adjusts each of the one or more selected offset adjustment corrections to their respective optimal points and/or each of one or more non-selected offset adjustment corrections to a corresponding one of a plurality of possible offset corrections to provide one or more adjusted offset adjustment corrections. A tracking mode procedure optimizes the one or more adjusted offset adjustment corrections.
Abstract:
A communication system may include a number of communication channels operating in accordance with one or more communication standards. The channels may generate data clocks from one or more master clock signals. The phase of the data clocks may be aligned using phase detectors for determining respective phase relationships and using phase interpolators for adjusting respective clock phases. The communication system may include communication channels that operate at different data clock frequencies. These systems may divide their respective data clocks in order to achieve a common clock frequency for use in their phase alignment. The phase detectors and associated circuitry may be disabled to save power when not in use.
Abstract:
Reference-less repeating circuits provide significant advantages over repeating circuits requiring external frequency references. These repeating circuits eliminate the need for external frequency references provide significant power, layout, and physical isolation advantages. Digitally controlled reference-less repeating circuits have a relatively narrow frequency detection range, but typically consume significantly less power than analog repeating circuits while providing data rate flexibility, particularly at lower data rates. Due to the narrow frequency detection range of digitally controlled reference-less repeating circuits, efficient frequency estimation techniques allow these circuits to quickly lock to an input signal, and provide an accurate repeated output signal.
Abstract:
A device for passive equalization and slew-rate control of a signal includes a first branch and a second branch. The first branch includes a first driver coupled in series with an equalization capacitor. The second branch includes a second driver coupled in series with a resistor. The second branch may be coupled in parallel to the first branch. The first branch may be configurable to enable either passive equalization or slew-rate control of the signal based on a mode control signal.