摘要:
A system and method for seamlessly reprogramming clock frequencies includes a phase locked loop (PLL) that generates CPU and double data rate (DDR) clocks. A crystal is used to generate a reference clock. The CPU clock and the reference clock are inputs to a first multiplexer, and the DDR clock and reference clock are inputs to a second multiplexer. In normal operation the multiplexers provide the CPU and DDR clock signal as outputs. To reprogram the clock frequencies and reset the PLL, (1) the reference clock signal is selected to be the output of both multiplexers, so the device is running on the internal reference clock. The mux switching is synchronized with the CPU and DDR clock signals. (2) The PLL is reprogrammed, its internal voltage-controlled oscillator is reset, and the PLL is restarted at the new desired frequency. (3) When the new PLL frequency output is stable, the multiplexers are switched back to the PLL-generated CPU and DDR clocks, synchronously with the reference clock signal.
摘要:
A system and method for seamlessly reprogramming clock frequencies includes a phase locked loop (PLL) that generates CPU and double data rate (DDR) clocks. A crystal is used to generate a reference clock. The CPU clock and the reference clock are inputs to a first multiplexer, and the DDR clock and reference clock are inputs to a second multiplexer. In normal operation the multiplexers provide the CPU and DDR clock signal as outputs. To reprogram the clock frequencies and reset the PLL, (1) the reference clock signal is selected to be the output of both multiplexers, so the device is running on the internal reference clock. The mux switching is synchronized with the CPU and DDR clock signals. (2) The PLL is reprogrammed, its internal voltage-controlled oscillator is reset, and the PLL is restarted at the new desired frequency. (3) When the new PLL frequency output is stable, the multiplexers are switched back to the PLL-generated CPU and DDR clocks, synchronously with the reference clock signal.
摘要:
A system and method are used to allow high speed communication between a circuit and an external device. The system and method include a PLL with multiple phased outputs configured to be controlled digitally, a deskew PLL configured to align a clock of controller circuitry to interface circuitry, and a phase interpolated voltage controlled delay line configured to phase shift incoming signals. Analog design techniques of phase interpolation accurately position clocks and strobe signals that are required for high speed interfaces. The high speed interface is for transmitting and receiving signals from the external device, for example, a DDR DRAM.
摘要:
The present invention relates to frequency dividers. The frequency divider comprises an input, a counter, a first comparator, an interconnect, and an output. The counter has a counter reset port and is configured to receive a clock signal from the input and to produce a sum signal. The first comparator is configured to receive the sum signal, to compare the sum signal to a first integer, and to produce a first comparison signal. The interconnect is configured to convey the first comparison signal from the first comparator to the counter reset port. The output coupled to the first comparator. The clock signal has a periodic waveform. The sum signal represents a first sum, which equals a number of waveforms of the clock signal received by the counter after the counter has been reset. In a first embodiment, the first integer is selectable from a set of at least three consecutive integers. In a second embodiment, a frequency of the clock signal is at least 1.5 gigahertz. A third embodiment includes the features of both the first embodiment and the second embodiment.
摘要:
Methods of processing incoming documents. The methods may comprise receiving a plurality of documents in electronic form and classifying each of the plurality of documents into at least one of a plurality of document classifications. The methods may also comprise extracting metadata from the plurality of documents. In addition, the methods may comprise executing a first workflow for processing documents classified in a first document classification selected from the plurality of document classifications and executing a second workflow for processing documents classified in a second document classification selected from the plurality of document classifications.
摘要:
A system and method are used to allow high speed communication between a chip and an external device. The system and method include a PLL with multiple phased outputs configured to be controlled digitally, a deskew PLL configured to align a clock of controller circuitry to interface circuitry, and a phase interpolated voltage controlled delay line configured to phase shift incoming signals. Analog design techniques of phase interpolation accurately position clocks and strobe signals that are required for high speed interfaces. The high speed interface is for transmitting and receiving signals from the external device, for example, a DDR DRAM.
摘要:
A system for generating multiple synthesized clocks having an input terminal for receiving a reference signal, a phase locked loop circuit coupled to the input signal terminal, where the phase locked loop circuit is capable of generating a plurality of output signals that are frequency locked to the reference signal and having a plurality of different phases, a phase rotator coupled to the phase locked loop circuit, where the phase rotator generates an even greater plurality of phases.
摘要:
At least one method for indicating a weather condition includes indexing a storm based on two or more parameters. One of the parameters is a travel speed of the storm and a second parameter is a location of the storm. The method further includes providing a time before the storm impacts a recipient based on the travel speed of the storm and a track distance to the recipient location. The method further includes delivering the time before the storm impacts the location to the recipient.
摘要:
An embodiment of the invention provides an apparatus and method for varying a voltage controlled oscillator (VCO) sensitivity. A VCO has an oscillator portion coupled to a variable current supply. The variable current supply has one or more enabled variable current cells. The enable variable current cell input provides a control to change the VCO sensitivity. In an example, the oscillator portion has a ring oscillator. In an example, the variable current supply has at least two variable current cells that supply the control current. A binary control signal alters a quantity of variable current cells that supply the control current. Each successive variable current cell has an output current substantially equal to twice that of a prior variable current cell.
摘要:
A system and method are used to allow high speed communication between a chip and an external device. The system and method include a PLL with multiple phased outputs configured to be controlled digitally, a deskew PLL configured to align a clock of controller circuitry to interface circuitry, and a phase interpolated voltage controlled delay line configured to phase shift incoming signals. Analog design techniques of phase interpolation accurately position clocks and strobe signals that are required for high speed interfaces. The high speed interface is for transmitting and receiving signals from the external device, for example, a DDR DRAM.