Abstract: Integrated circuits such as multi-channel receivers may require loop inductors resistant to electromagnetic field interference. Such loop inductors may include multiple non-overlapping loops each defining a corresponding dipole, the multiple dipoles summing to zero, with at least one of said loops having unequal areas. The multiple non-overlapping loops may include: a center loop defining a central magnetic dipole; and a plurality of peripheral loops equally spaced around a perimeter of the center loop, each peripheral loop defining a peripheral magnetic dipole oriented opposite the central magnetic dipole, the plurality of peripheral loops substantially canceling a field from the central magnetic dipole. The total number of loops may be odd, with particular embodiments of three, five, and seven loop designs disclosed. Single and multi-turn embodiments are provided.

Abstract: Mass-manufactured cables suitable for large communication centers may convert from differential PAM4 interface signaling to parallel single-ended NRZ transit signaling at 53.125 GBd to provide bidirectional data rates up to 800 Gbps and beyond. One illustrative cable embodiment includes: electrical conductors connected between a first connector and a second connector, each adapted to fit into an Ethernet port of a corresponding host device to receive an electrical input signal to the cable conveying an outbound data stream from the host device and to provide an electrical output signal from the cable conveying an inbound data stream to that host device. The electrical input and output signals employ differential PAM4 modulation to convey the inbound and outbound data streams.

Abstract: Modular layout design units are provided with an internal channel for multi-directional distribution of a shared signal. In one illustrative embodiment, an integrated circuit includes: one or more modular units, each modular unit having an internal channel for signal distribution. The internal channel possesses: an edge connection on each edge of the modular unit; a hub node coupled to each edge connection by a respective bi-directional buffer having an incoming buffer and an outgoing buffer with at least one of the incoming and outgoing buffers disabled, the bi-directional buffers cooperating to steer a signal from a selectable one of the edge connections to one or more of the other edge connections; and a tap providing the signal for use by internal circuitry of the modular unit.

Abstract: Integrated circuits such as multi-channel receivers may require loop inductors resistant to electromagnetic field interference. Such loop inductors may include multiple non-overlapping loops each defining a corresponding dipole, the multiple dipoles summing to zero, with at least one of said loops having unequal areas. The multiple non-overlapping loops may include: a center loop defining a central magnetic dipole; and a plurality of peripheral loops equally spaced around a perimeter of the center loop, each peripheral loop defining a peripheral magnetic dipole oriented opposite the central magnetic dipole, the plurality of peripheral loops substantially canceling a field from the central magnetic dipole. The total number of loops may be odd, with particular embodiments of three, five, and seven loop designs disclosed. Single and multi-turn embodiments are provided.

Abstract: Integrated circuits such as multi-channel receivers may require loop inductors resistant to electromagnetic field interference. Such loop inductors may include multiple non-overlapping loops each defining a corresponding dipole, the multiple dipoles summing to zero, with at least one of said loops having unequal areas. The multiple non-overlapping loops may include: a center loop defining a central magnetic dipole; and a plurality of peripheral loops equally spaced around a perimeter of the center loop, each peripheral loop defining a peripheral magnetic dipole oriented opposite the central magnetic dipole, the plurality of peripheral loops substantially canceling a field from the central magnetic dipole. The total number of loops may be odd, with particular embodiments of three, five, and seven loop designs disclosed. Single and multi-turn embodiments are provided.

Abstract: High-data rate channel interface modules and equalization methods employing a finite impulse response (FIR) analog receive filter. Embodiments include an illustrative channel interface module having multiple amplifier-based delay units arranged in a sequential chain to convert an analog input signal into a set of increasingly-delayed analog signals that are weighted and combined together with the analog input signal to form an equalized signal; and a symbol decision element operating on the equalized signal to obtain a sequence of symbol decisions. An interface that extracts received data from the sequence of symbol decisions. The delay units may employ one or more delay cells each having a common-source amplifier stage followed by a source follower output stage, the two stages providing approximately equal portions of the propagation delay. An enhanced gate-to-drain capacitance in the common-source amplifier may increase propagation delay while reducing bandwidth limitations.

Abstract: High-data rate channel interface modules and equalization methods employing a finite impulse response (FIR) analog receive filter. Embodiments include an illustrative channel interface module having multiple amplifier-based delay units arranged in a sequential chain to convert an analog input signal into a set of increasingly-delayed analog signals that are weighted and combined together with the analog input signal to form an equalized signal; and a symbol decision element operating on the equalized signal to obtain a sequence of symbol decisions. An interface that extracts received data from the sequence of symbol decisions. The delay units may employ one or more delay cells each having a common-source amplifier stage followed by a source follower output stage, the two stages providing approximately equal portions of the propagation delay. An enhanced gate-to-drain capacitance in the common-source amplifier may increase propagation delay while reducing bandwidth limitations.

Abstract: An illustrative multi-lane communication method includes: (a) receiving receive signals on different receive channels; (b) converting each of the receive signals into a lane of a multi-lane receive data stream, wherein said converting includes demodulation and error measurement; (c) determining remote pre-equalizer adaptation information based in part on the error measurement; (d) detecting alignment markers in the multi-lane receive data stream; (e) extracting local pre-equalizer adaptation information in, or proximate to, the alignment markers in the multi-lane receive data stream; (f) using the local pre-equalizer adaptation information to adjust coefficients of a local pre-equalization filter; (g) periodically inserting an alignment marker in a multi-lane transmit data stream, wherein the remote pre-equalizer adaption information is included in, or inserted proximate to, the alignment markers; and (h) transforming each lane of the multi-lane transmit data stream into a transmit signal, wherein said transf

Abstract: An illustrative driver embodiment supplies an electrical transmit signal to an emitter module in response to an input bit stream. The illustrative driver embodiment includes: a voltage supply node which may be powered via a parasitic series inductance; a transmit signal buffer that drives the electrical transmit signal with current from the voltage supply node, the electrical transmit signal including transitions at bit intervals as dictated by the input bit stream; and an auxiliary signal buffer that supplies an auxiliary signal with current from the voltage supply node to an auxiliary module having an input impedance matched to an input impedance of the emitter module, the auxiliary signal having a transition at every bit interval where the electrical transmit signal lacks a transition.

Abstract: An illustrative driver embodiment supplies an electrical transmit signal to an emitter module in response to an input bit stream. The illustrative driver embodiment includes: a voltage supply node which may be powered via a parasitic series inductance; a transmit signal buffer that drives the electrical transmit signal with current from the voltage supply node, the electrical transmit signal including transitions at bit intervals as dictated by the input bit stream; and an auxiliary signal buffer that supplies an auxiliary signal with current from the voltage supply node to an auxiliary module having an input impedance matched to an input impedance of the emitter module, the auxiliary signal having a transition at every bit interval where the electrical transmit signal lacks a transition.

Abstract: A multichannel receiver includes multiple receiver modules, each having: a voltage-controlled oscillator that generates a clock signal with a controllable frequency; a phase interpolator that applies a controllable phase shift to the clock signal to provide a sampling signal; a sampling element that produces a digital receive signal by sampling an analog receive signal in accordance with the sampling signal; a timing error estimator that operates on the digital receive signal to provide timing error estimates; a phase control filter that derives, from the timing error estimates, a phase control signal supplied to the phase interpolator, wherein the phase control signal minimizes a phase error between the sampling signal and the analog receive signal; and a frequency control filter that derives, from the timing error estimates, a frequency control signal for controlling the clock signal frequency, wherein the frequency control signal minimizes a frequency offset between the clock signal and the analog receive

Abstract: Disclosed is at least one flash analog-to-digital converter embodiment having a linear voltage ladder, a set of comparators each of which is coupled to one or more operational amplifiers by a sampling switch. Each of the sampling switches samples the comparator output, using the parasitic capacitance of the operational amplifier to hold the voltage. The sampling switches may be single transistors. Some embodiments further include, for each comparator, multiple operational amplifiers each of which drives a binary latch via a gating switch. The gating switches operate in sequence to distribute sequential samples to different latches. At least some embodiments of the flash converter further include an automatic gain control (AGC) that has both differential input terminals and differential output terminals. In such embodiments the comparators compare the differential output of the AGC to a differential reference voltage, and may further provide the result as a differential signal.

Abstract: Disclosed is at least one flash analog-to-digital converter embodiment having a linear voltage ladder, a set of comparators each of which is coupled to one or more operational amplifiers by a sampling switch. Each of the sampling switches samples the comparator output, using the parasitic capacitance of the operational amplifier to hold the voltage. The sampling switches may be single transistors. Some embodiments further include, for each comparator, multiple operational amplifiers each of which drives a binary latch via a gating switch. The gating switches operate in sequence to distribute sequential samples to different latches. At least some embodiments of the flash converter further include an automatic gain control (AGC) that has both differential input terminals and differential output terminals. In such embodiments the comparators compare the differential output of the AGC to a differential reference voltage, and may further provide the result as a differential signal.