摘要:
A data processing system having a compression and decompression apparatus based on the Lempel-Ziv algorithm. The compression apparatus includes an array section having a circular history CAM unit for receiving and storing one or more data elements and a coding unit for determining whether received data elements previously have been stored in the history CAM unit and are a candidate for compression. If a received data element matches at least one of the stored data elements, a PS logic section determines whether there is the presence of a string. An encoding section identifies the address of the matching stored data element in a string and the length of the string. The compression apparatus generates a compression token comprising an identification of whether a data element is compressed, the length of the coded data within a plurality of predetermined data length categories and an address. The compression apparatus uses a particular hardware implementation of the PS logic section.
摘要:
A voltage-controlled oscillator (VCO) comprising an odd number of delay stage circuits. Each delay stage circuit operates between supply voltages VDD and VSS (VDD>VSS) and comprises (1) an input node, (2) an output node, (3) an inverting circuit, and (4) an electric discharge path coupling the output node to VSS. The electric discharge path includes a switch circuit and a resistance adjusting circuit electrically coupled in series between the output node and VSS. In response to an input signal rising at the input node, the inverting circuit decreases an output signal at the output node, and the electric discharge path opens to help pull the output signal down faster. In response to an input signal falling at the input node, the inverting circuit increases the output signal at the output node, and the electric discharge path closes to minimize its own effect.
摘要:
A method and structure for calibrating an analog to digital converter comprises an input signal; a driver receiving the input signal, wherein the driver outputs a driver output signal; a flash circuit receiving the driver output signal, wherein the flash circuit outputs a comparison result equaling 2n−1 digital outputs; an encoding logic unit encoding the comparison result into n digital bits as an output signal; a calibration engine outputting a calibration input adjust signal, a reference adjust signal, a driver gain adjust signal, a driver offset adjust signal; and a calibration input circuit receiving the calibration input adjust signal, wherein the driver receives the driver gain adjust signal and the driver offset adjust signal, wherein the flash circuit receives the reference adjust signal, wherein the calibration engine receives n digital bits, and controls an operation of the driver or flash circuit based on the output signal.
摘要:
A voltage boosting circuit for an "H-driver," providing for each "pull-up" switch in the H-driver a switching shunt that charges a capacitor from a supply voltage when the "pull-up" switch is open and couples the capacitor directly to the write head when the "pull-up" switch is closed. The side of the capacitor which is not directly coupled to the write head is coupled to the data signal (or its inverse, in the case of the capacitor for the otherwise identical circuit serving the parallel half of the "H-driver") through a buffer which sets the voltage at the signal level (or its inverse), thereby dumping the charge to the write head and elevating the voltage of the write head significantly above the supply voltage. The identical circuit serving the parallel half of the "H-driver" similarly boosts the negative going transition voltage.
摘要:
A data processing system having a compression and decompression apparatus based on the Lempel-Ziv algorithm. The compression apparatus includes an array section having a circular history CAM unit for receiving and storing one or more data elements and a coding unit for determining whether received data elements previously have been stored in the history CAM unit and are a candidate for compression. If a received data element matches at least one of the stored data elements, a PS logic section determines whether there is the presence of a string. An encoding section identifies the address of the matching stored data element in a string and the length of the string. The compression apparatus generates a compression token comprising an identification of whether a data element is compressed, the length of the coded data within a plurality of predetermined data length categories and an address. The compression apparatus uses a particular hardware implementation of the PS logic section.
摘要:
According to the preferred embodiment, a self-biased phase-locked loop is provided that overcomes the limitations of the prior art bias methods and apparatus. In general, a self-biased current controlled semiconductor device, typically a current controlled oscillator, is self biased by the use of a first feedback path, typically provided by a phase-locked loop, where the feedback path provides a control current for controlling the current controlled device. A second feedback path, typically a pair current mirrors, serves as a bias loop having unity gain. The bias loop provides a bias current that is responsive to the control current. This device has the advantage of being self biasing, thus no other biasing circuitry is required.
摘要:
A communication system for transmitting data between cores embedded in an integrated circuit on a silicon chip. Communication system includes transmitter circuitry for wirelessly transmitting data between cores and receiver circuitry for wirelessly receiving the transmission of data from other cores. Both transmitter circuitry and receiver circuitry may include of a phase-locked loop circuit having a voltage-controlled oscillator. Each core may transmit and receive data on a unique frequency with respect to other cores embedded in an integrated circuit on a silicon chip or transmit and receive data on the same frequency as other cores embedded in an integrated circuit on a silicon chip. Groups of cores may share transmitter and receiver circuitry.
摘要:
A structure and associated method for controlling an amplitude of oscillation in a voltage controlled oscillator. The voltage controlled oscillator circuit comprises a drive circuit, an inductor/capacitor (LC) tank circuit, and a diode. The LC tank circuit and the drive circuit collectively comprise a first oscillating node and a second oscillating node. The first oscillating node is adapted to have a first voltage. The second oscillating node is adapted to have a second voltage. The first diode is adapted to control an amplitude of the first voltage and an amplitude of the second voltage.
摘要:
A complementary metal oxide semiconductor PLL includes an input for receiving a reference frequency and a feedback loop for determining a phase error based on the reference frequency. The feedback loop includes a calibration DAC (amplifier with a digital gain control input) and a bandwidth DAC in series. The ICO controller is well known in control theory as a PI or proportional-integral controller. A proportional path supplies a proportional signal to the calibration amplifier and an integral path supplies an integral signal (a signal that is integrated in time) to the calibration amplifier.
摘要:
The present invention provides an improved method and apparatus for independently controlling phase and frequency using an oscillator having a plurality of stages in combination with a phase selector within a digitally controlled phase-locked loop, preferably, a read phase locked loop. The present invention provides a digitally controlled variable phase of the read timing loop in read channel integrated circuits associated with data storage devices. The phase selector has a digitally controlled fine interpolator with 12 states for further fine interpolation between at least two multiplexer phase outputs to provide a single phase output selected from a range comprising at least 2&pgr; in selectable variable phase increments of 2&pgr;/96 radian. The combined oscillator with the phase selector within a phase locked loop controls phase by exact fractional increments of equally space phases of the operating frequency within the phase locked loop, therein controlling phase at all operating frequencies.