Abstract: An integrated circuit includes analog test cells to determine if an analog signal is within a predetermined voltage or current range. The test cell uses one or more analog reference signals to establish boundaries of a test range. Different embodiments of the analog test cells selectively test multiple analog signals provided in an integrated circuit. A test system can be provided to test multiple analog signals of an integrated circuit by scanning multiple analog test cells distributed throughout the integrated circuit and providing the test data for analysis. An analog circuit of an integrated circuit can be tested at different stages in manufacturing, including during a wafer stage prior to separation of individual circuit dice. Further, analog circuitry can be tested and characterized without the need for analog or digital/analog testers. In contrast, a digital only tester can be used to test analog circuitry.

Abstract: A charge pump circuit that can be used in a phase-locked loop circuit provides a differential output signal that has a common mode voltage. The charge pump includes a common mode feedback circuit that maintains a predetermined common mode voltage on output connection of the charge pump. The charge pump can operate with a small supply voltage. In one embodiment, the charge pump can operate with a supply voltage that is less than 2.0 volts and maintain a common mode voltage that is less than 1.0 volts. The common mode feedback circuit includes current mirror circuitry and bias circuitry. The current mirror circuitry and the bias circuitry adjust the common mode voltage in response to input signals.

Abstract: A communication system for transferring digital data over a distribution network is described. The communication system includes an interface for receiving successive strings of digital data from a source, each string representing a certain number of bits. The system also includes a symbol mapper for converting the strings into a sequence of symbols representing a constellation of discrete values of the amplitude and phase of a carrier for a predetermined period. The constellation is rotationally asymmetric for valid ones of the data strings. The system further includes a modulator for synthesizing a plurality of orthogonal carriers from said symbols a transmitter for sending the modulated carriers over a distribution network.

Abstract: A current source calibration circuit and methodology reduce noise generated by current switching. In one embodiment, the calibration circuit provides a random or pseudo-random clock signal to control a switching of calibration circuit. A clock signal generator has been described that provide a number of clock signals having different phases. In one embodiment, the clock signals are used to select a current source of a DAC for calibration. By using a random clock to select the current source, noise, which is generated by switching a primary current source with a backup current source, is spread out over a wider frequency range.

Abstract: A scalable physical coding sublayer (PCS) can be adjusted to provide different combinations of communication channels and data widths. The PCS can use 8B/10B encoders having a disparity input connection and at least one disparity output connection. In one embodiment, the encoder has both a synchronous and an asynchronous disparity output connection. The encoder can be coupled with additional encoders to provide an expanded width channel of 16B/20B encoding. Additional configurations are possible. In expanded operation, only one of the encoders needs to output special codes. The encoders, therefore, include a slave input connection to place the encoder in a slave mode so that a special code is replaced with an inert special code. All but one encoder in an expanded system are slave encoders. An idle input connection is also provided in the encoders to place the encoder in an idle mode where pre-defined data is output from the encoder.

Abstract: A segmented digital-to-analog converter (DAC) has been described that uses a two-step calibration process to calibrate current sources to a single primary reference source. In one embodiment, the DAC includes sub-DACs, a reference generator circuit and a primary, or golden, reference source. Current sources of both the sub-DACs and the reference generator are calibrated to a golden current source or primary reference current. In one embodiment, the current sources each include a transistor coupled so that a gate voltage can be adjusted during calibration. The multiple current sources of the reference generator are first calibrated to the primary reference source. The calibrated output currents of the reference generator are then used to calibrate current sources in the sub-DACs.

Abstract: A method for controlling a plurality of service units in a telecommunications system with a multi-carrier transmission scheme is provided. Specifically, in one embodiment, the method includes broadcasting control signals for the service units over a plurality of control channels distributed in a number of subbands of a frequency bandwidth. The method further includes identifying the service unit to use the control signal with an identifier.

Abstract: A scanning method for establishing communication between a head end and a plurality of remote units in a multi-point to point communication system is described. The method includes transmitting information from the head end to the plurality of remote units in a plurality of regions of a first frequency bandwidth, each of the regions having at least one control channel associated therewith, identification information corresponding to each of the remote units of the plurality of remote units being periodically transmitted from the head end on the at least one control channel of one of the plurality of regions of the first frequency bandwidth.

Abstract: A memory device has a segmented memory cell array that take a row address and a column address and allows for data words in a column page to be read internally in parallel for faster access. The memory device employs a segmented memory array that routes column address and column address+1 to the segments. This allows for a random starting data word in the column page, while the data words in the next column page (column address+1) are loaded into the memory array segments before the starting data word. When the data page mode or linear burst access crosses a column address boundary the next data words in column address+1 are available and no wait states need to be asserted to allow for new column address values to propagate.

Abstract: A translator includes an initial circuit device configured to charge a translator output to a first voltage level in response to a change in an input signal. The translator further includes a sensing device configured to detect the output's potential approaching the first voltage level and smoothly shift charging functions over to a secondary circuit device, which will continue to charge the output up to a second voltage level.

Abstract: A flash memory device incorporating redundant rows. The memory device includes a memory array, control circuitry and a register. The control circuitry controls operations to the memory array. The register stores an address of a defect in the memory array and data indicating a type of defect associated with the address. The control circuitry increments row addresses during an erase operation based on the type of defect stored in the register.

Abstract: A translator includes an initial circuit device configured to charge a translator output to a first voltage level in response to a change in an input signal. The translator further includes a sensing device configured to detect the output's potential approaching the first voltage level and smoothly shift charging functions over to a secondary circuit device, which will continue to charge the output up to a second voltage level.

Abstract: A method of transmitting data in a communication system is provided. The method includes adjusting upstream power levels in a multipoint-to-point communications system having a head end and a plurality of service units is provided. The method includes measuring power levels of signals from the service units at the head end and comparing the power levels with a nominal power level. Further, the method provides at least one coarse adjustment at the service units to correct for large variations between the measured power level nominal power level and at least one fine adjustment at the head end to correct for smaller variations between the measured power level and the nominal power level.

Abstract: An integrated circuit input buffer system includes numerous buffers used to receive input signals. The buffer system controls the buffers in a manner that places some of the buffers in a standby mode while other buffers are active. The integrated circuit input buffer system reduces the capacitive load on any individual buffer. The buffers can be activated in a variety of patters, such as sequential activation. In one embodiment, the buffers have differential transistors coupled to receive differential input signals. The differential transistors are coupled to conduct a total current defined by a tail current circuit. The buffers are placed in a standby state by electrically isolating the tail current from the differential transistors. In one embodiment, a standby transistor is electrically located between the differential transistors and a tail current transistor. The differential transistors conduct a trickle current during the standby state.

Abstract: A method and apparatus for trimming a non-volatile memory cell. One method comprising, erasing the memory cell below a desired voltage threshold (Vt) level, applying a program pulse to the memory cell, reading the memory cell, comparing a current conducted by the memory cell with an externally provided reference current using a sense amplifier that is internal to a memory device that contains the memory cell, producing a digital output based on the comparison of the currents and applying successive program pulses until the digital output changes from one logic state to another.

Abstract: Methods for forming multiple dielectric layers at low temperatures include forming a number of metallic layers on a substrate and oxidizing the metallic layers to different dielectric oxides. Oxidation is performed one layer at a time, or all layers together. Dielectric layers thus formed have multiple different oxides in layers, reducing defects, providing high capacitance, and low leakage currents.

Abstract: A synchronous flash memory includes an array of non-volatile memory cells. The memory device has a package configuration that is compatible with an SDRAM. The synchronous flash memory device includes an array of non-volatile memory cells arranged in a plurality of addressable blocks. Control circuitry is provided to access the plurality of addressable blocks to perform a write or erase operation on memory cells contained in a first one of the plurality of addressable blocks. The control circuitry performs the write or erase operation in response to an externally provided command sequence and prohibits the write or erase operation if an externally provided bank address changes during the externally provided command sequence.

Abstract: A sliding power switch is provided. The switch includes a power interface module having a first power port, a second power port and a third power port. The switch also includes a shunt adapted to engage with the power interface module in a first position so as to provide a first electrical path from one of the first, second, and third power ports to another one of the first, second, and third power ports and a second position so as to provide a second electrical path from one of the first, second, and third power ports to another of the first, second, and third power ports. The switch further includes a shunt retainer coupled to the shunt and adapted to aid in placing and removing the shunt from the first and second positions and a slide actuator adapted to engage with and enable the shunt retainer to slide from the first position to the second position.

Abstract: Clock generator circuits containing a delay circuit having at least one delay element and at least one bypass are arranged to activate the bypass in response to a first logic level presented at the input of the delay circuit and to deactivate the bypass in response to a second logic level presented at the input of the delay circuit. Such clock generators are useful in synchronous memory devices for generating internal clock signals of fixed pulse width from an external clock signal. The internal clock signal is generated from a triggering event, such as a rising edge of the external clock signal, and has a pulse width determined by the delay time of the delay element. The first logic level is generated in response to the beginning of an output pulse of the clock generator.

Abstract: A synchronous flash memory includes an array of non-volatile memory cells. The memory device has a package configuration that is compatible with an SDRAM. In one embodiment, the present invention can include a memory device comprising an array of memory cells arranged in addressable blocks and an n-bit status register. The memory includes a control circuit coupled to the n-bit status register to program a first bit of the n-bits to a first state indicating if a program operation is being performed on the array. The control circuit further programs second and third bits of the n-bits to identify one of the addressable blocks while the array is being programmed. A method of operating a memory device includes initiating a write operation on a first programmable location of the memory device using a first processor, and reading a status from status data stored in the memory device during the write operation. The status indicates an identification of the first programmable location.