Abstract: A multi-PAM equalizer receives an input signal distorted by inter-symbol interference (ISI) and expressing a series of symbols each representing one of four pulse amplitudes to convey two binary bits of data per symbol. High-order circuitry resolves the most-significant bit (MSB) of each two-bit symbol, whereas low-order circuitry 115 resolves the immediate least-significant bit (LSB). The MSB is used without the LSB for timing recovery and to calculate tap values for both MSB and LSB evaluation.

Abstract: A serial receiver combines continuous-time equalization, analog interleaving, and discrete-time gain for rapid, efficient data reception and quantization of a serial, continuous-time signal. A continuous-time equalizer equalizes a received signal. A number N of time-interleaved analog samplers sample the equalized continuous-time signal to provide N streams of analog samples transitioning at rate reduced by 1/N relative to the received signal. A set of N discrete-time variable-gain amplifiers amplify respective streams of analog samples. A quantizer then quantizes the amplified streams of analog samples to produce a digital signal.

Abstract: A multi-PAM equalizer receives an input signal distorted by inter-symbol interference (ISI) and expressing a series of symbols each representing one of four pulse amplitudes to convey two binary bits of data per symbol. High-order circuitry resolves the most-significant bit (MSB) of each two-bit symbol, whereas low-order circuitry 115 resolves the immediate least-significant bit (LSB). The MSB is used without the LSB for timing recovery and to calculate tap values for both MSB and LSB evaluation.

Abstract: Disclosed is a system where indicators of the relative phase differences between combinations of clocks in a multi-phase clock system are developed and/or measured. These indicators convey information regarding which phase difference between a given pair of the clocks is greater than (or less than) the phase difference between another pair of the clocks. This information is used to sort/rank/order phase differences between the various combinations of pairs of clocks according to their phase differences. This ranking is used to select the pair of clocks to be adjusted.

Abstract: A multi-PAM equalizer receives an input signal distorted by inter-symbol interference (ISI) and expressing a series of symbols each representing one of four pulse amplitudes to convey two binary bits of data per symbol. High-order circuitry resolves the most-significant bit (MSB) of each two-bit symbol, whereas low-order circuitry 115 resolves the immediate least-significant bit (LSB). The MSB is used without the LSB for timing recovery and to calculate tap values for both MSB and LSB evaluation.

Abstract: A multi-PAM equalizer receives an input signal distorted by inter-symbol interference (ISI) and expressing a series of symbols each representing one of four pulse amplitudes to convey two binary bits of data per symbol. High-order circuitry resolves the most-significant bit (MSB) of each two-bit symbol, whereas low-order circuitry 115 resolves the immediate least-significant bit (LSB). The MSB is used without the LSB for timing recovery and to calculate tap values for both MSB and LSB evaluation.

Abstract: A voltage-mode differential driver may include a first nominal path that selectively couples a first supply or a second supply to a first output terminal in response to an input data. The voltage-mode differential driver may further include a first capacitive boost path that selectively couples the first supply or the second supply to the first output terminal responsive to the input data. The first capacitive boost path may be selectively enabled to provide a boost current to be added to a current from the first nominal path resulting in an output current to be provided to the first output terminal.

Abstract: In some communications circuits a phenomenon called duty-cycle distortion—that is, a distortion of the apparent duration of the pulses in clock signals—causes the circuits to read clock signals as having a different duration than intended. Accordingly, the inventors devised unique circuitry for correcting or preventing this distortion. One exemplary circuit uses a voltage divider, comprising a pair of transistors, to set the DC or average voltage of the clock signals input to the digital circuit at a level approximating the logic threshold voltage of the digital circuit. In another example, a feedback circuit drives the DC or average voltage of signals input to the digital circuit to match a reference voltage that is substantially equal to the logic threshold voltage. In both examples, equating the DC or average voltage of the clock signals to the logic threshold voltage of the digital circuit reduces or prevents duty-cycle distortion.

Abstract: A typical occurrence in communication circuits, such as transmitters and receivers, is the internal transfer of a sequence of pulses, known as a clock signal, from an amplifier to a digital circuit. For proper operation, it is critical that the digital circuit accurately comprehends the clock signal. However, in some communications circuits a phenomenon called duty-cycle distortion—that is, a distortion of the apparent duration of the pulses in clock signals—causes the digital circuit to read the clock signals as having a longer or shorter duration than intended. Accordingly, the inventors devised unique circuitry for correcting or preventing this distortion. One exemplary circuit uses a voltage divider, comprising a pair of transistors, to set the DC or average voltage of the clock signals input to the digital circuit at a level approximating the logic threshold voltage of the digital circuit.