摘要:
A data communication system includes circuitry to assure components respond to variations in the time length of the valid data window or “eye” of the high speed data communication signal. A self-test portion of the system periodically injects the effects of phase jitter into the data communication signal to assure the system performs properly.
摘要:
Methods and arrangements to determine phase adjustments for a sampling clock of a clock and data recovery (CDR) loop based upon subsets of data samples, or values, derived from an incoming data signal are disclosed. In particular, embodiments extend the CDR loop by slowing the clock rate with respect to the sampling clock. For instance, the slower clock rate may be implemented by dividing the frequency of the sampling clock by a number such as 128, slowing a sampling clock frequency designed to handle multiple gigabits per second (Gbps) to a frequency of less than one kilohertz (Khz). In addition to the reduced power consumption realized by operating at a lower frequency, the slower clock rate allows components of the CDR loop circuitry to operate a lower operating voltage reducing power consumption by the CDR loop even more.
摘要:
A data receiver is provided which is operable to receive a signal controllably pre-distorted and transmitted by a transmitter, to generate information for adjusting the pre-distortion applied to the signal transmitted by the transmitter, and to transmit the information to the transmitter. The receiver is further operable to perform adaptive equalization to receive the signal transmitted by the transmitter.
摘要:
A data communication system includes a transmitter unit and a receiver unit. The transmission unit has a transmission characteristic that is adjustable in accordance with equalization information. The transmission unit is operable to transmit a predetermined signal and the receiver unit is operable to receive the predetermined signal. The receiver unit is further operable to generate the equalization information by examining the eye opening of the received signal, and to transmit the equalization information to the transmitter unit.
摘要:
A phase adjustment apparatus and method adjusts phase or timing bias of a sample clock in a data receiver system by determining a time adjustment value as a function of equalizer feedback. The time adjustment value is then applied to a device capable of adjusting a timing bias of a sample clock.
摘要:
A structure and method for damping LC (inductance-capacitance) ringing in integrated circuit (IC) power distribution systems. The structure comprises a resistance electrically connected in parallel with a plurality of electrical switches. The resistance and electrical switches are electrically connected in series with the package and on-chip power distribution circuit. When on-chip switching activity creates a sudden and appreciable change in IC power demand the electrical switches are opened to temporarily increase the resistance in series with the power supply. This serves to dampen the power-distribution LC ringing. Later, the electrical switches are closed to shunt the series resistance and reduce the level of steady-state voltage drop in the power structure.
摘要:
A packaged semiconductor chip is provided which includes a semiconductor chip and a package element. The semiconductor chip includes a plurality of semiconductor devices and a plurality of conductive features disposed at an exterior face of the semiconductor chip. The package element has a plurality of external features conductively connected to the plurality of conductive features of the semiconductor chip. The semiconductor chip includes a monitored element including a conductive interconnect that conductively interconnects a first node of the semiconductor chip to a second node of the semiconductor chip. A detection circuit in the semiconductor chip is operable to compare a variable voltage drop across the monitored element with a reference voltage drop across a reference element on the chip at a plurality of different times during a lifetime of the packaged semiconductor chip so as to detect when the resistance of the monitored element is over threshold.
摘要:
An apparatus is provided which includes a common signal node operable to conduct a first signal, a first circuit coupled to the common signal node to utilize the first signal and a signal-handling element coupled to the common signal node. The signal-handling element includes an isolating circuit coupled to the first conductor, a second conductor operable to conduct an output of the isolating circuit, and a signal-handling circuit coupled to the second conductor. The signal-handling circuit is operable to perform a signal-handling function in response to the output of the isolating circuit. By virtue of the isolating circuit, the signal-handling circuit and the first circuit are isolated from the second conductor and the signal-handling circuit. Preferably, the achieved isolation permits a communication signal included in the first signal to be conducted within a communication apparatus with less capacitance, and producing less return loss of that signal.
摘要:
A voltage controlled oscillator (VCO) is provided which includes a threshold level setting circuit operable to set a lower variable threshold level and to set an upper variable threshold level. The VCO includes a frequency band selection unit operable to adjust a frequency band setting of the VCO to one of a plurality of frequency band settings. The VCO further includes a comparator operable to determine whether a control voltage of the VCO falls between the lower threshold level and the upper threshold level. The VCO further includes a threshold adjustment and calibration circuit operable to maintain the frequency band setting when the control voltage falls between the lower and upper threshold levels. Otherwise, when the control voltage lies below the lower threshold level, the lower threshold level is adjusted downward and the upper threshold level is adjusted upward, and when the control voltage lies above the upper threshold level, the frequency band selection is increased to a next higher frequency band.
摘要:
Systems are provided for generating and distributing a plurality of reference currents on an integrated circuit. More particularly, an integrated circuit is provided which includes a reference current generating system. The reference current generating system includes a first reference current generator disposed at a first location of the integrated circuit which is operable to generate a plurality of first reference currents. A plurality of second reference current generators are disposed at a plurality of second locations of the integrated circuit. Each of the second reference current generators are operable to generate a second reference current from one of the plurality of first reference currents. In a particular example, the first location at which the first reference current generator is disposed is a central location and the second locations are disposed remote from the first location.