Patent classifications
H03L7/0992
METHOD FOR UP-CONVERTING CLOCK SIGNAL, CLOCK CIRCUIT AND DIGITAL PROCESSING DEVICE
The present disclosure relates to a method for up-converting a clock signal, a clock circuit and a digital processing device. More specifically, provided is a method for up-converting a clock signal, comprising: employing a first clock sub-circuit to provide a clock signal having a first frequency to a chip; receiving an instruction to up-convert the clock signal having the first frequency to a clock signal having a second frequency; in response to receiving the instruction, causing a second clock sub-circuit to output the clock signal having the second frequency; and after the second clock sub-circuit outputs the clock signal having the second frequency, employing the second clock sub-circuit to provide the clock signal having the second frequency to the chip in place of the first clock sub-circuit.
CONTROLLER IN HIGH-SPEED SPI MASTER MODE
In view of defects in the prior art, the present disclosure provides a controller in a high-speed serial peripheral interface (SPI) master mode, where clock signals are provided by a phase locked loop (PLL), and the entire controller includes: a low-speed clock domain and a high-speed clock domain, where the PLL provides two main clock signals by different clock frequency dividers, provides a low-speed clock signal to the low-speed clock domain, and provides a high-speed source clock signal to the high-speed clock domain. By such technical solutions in the present disclosure, functions of different clock domains are divided through asynchronization of a high-speed SPI controller, and the function of a high-speed SPI flash access is implemented, thereby saving a read/write time. Especially in an application scenario of an SPI flash boot, the controller can greatly optimize a startup time.
Apparatus for Digitally Controlled Oscillators and Associated Methods
An apparatus includes a digitally controlled oscillator (DCO), which includes an inductor coupled in series with a first capacitor. The DCO further includes a second capacitor coupled in parallel with the series-coupled inductor and first capacitor, a first inverter coupled in parallel with the second capacitor, and a second inverter coupled back-to-back to the first inverter. The DCO further includes a digital-to-analog-converter (DAC) to vary a capacitance of the first capacitor.
CIRCUITRY AND METHODS FOR FRACTIONAL DIVISION OF HIGH-FREQUENCY CLOCK SIGNALS
An oscillator provides a plurality of clock signals, including a first clock signal having a first frequency and a first period, wherein each clock signal has the first frequency and is phase shifted from the first clock signal by an integer times a predetermined fractional amount of the first period. A multiphase frequency divider receives the plurality of clock signals and provides a divided clock output, and includes an integer frequency divider which provides the divided clock output based on a modified clock input and a clock selector which provides a current clock as the modified clock input during a first portion of the divided clock output and a next clock as the modified clock input during a subsequent portion of the divided clock output. The next clock is selected from the plurality of clock signals based on a selected fractional phase shift amount indicated by a sigma-delta modulator.
BAW OSCILLATORS WITH DUAL BAW TEMPERATURE SENSING
A temperature compensated oscillator circuit includes a first oscillator, a second oscillator, a first divider, a second divider, a frequency ratio circuit, and a temperature compensation circuit. The first divider is coupled to the first oscillator, and is configured to divide a frequency of a first oscillator signal generated by the first oscillator. The second divider is coupled to the second oscillator, and is configured to divide a frequency of a second oscillator signal generated by the second oscillator. The frequency ratio circuit is coupled to the first divider and the second divider, and is configured to determine a frequency ratio of an output of the first divider to an output of the second divider. The temperature compensation circuit is coupled to the frequency ratio circuit and the first oscillator, and is configured to generate a compensated frequency based on the frequency ratio and the first oscillator signal.
Data output apparatus and semiconductor apparatus including the data output apparatus
A semiconductor apparatus includes a memory controller and data storage configured to input and output data in synchronization with a clock signal provided from the memory controller. The data storage includes a memory cell array and a data output apparatus configure to output read data from the memory cell array by sensing a logic level of the read data during a low-level period of a first clock, which is an inverted signal of a divided clock of the clock signal, and a low-level period of a second clock, the second clock having a set to phase delay amount from the divided clock.
Mechanical shock detection and phase and frequency correction of a MEMS mirror
A system for driving a microelectromechanical system (MEMS) oscillating structure includes a phase error detector configured to generate a phase error signal based on measured event times and expected event times of the MEMS oscillating structure oscillating about a rotation axis; a disturbance event detector configured to detect a disturbance event based on the phase error signal and a disturbance threshold value; and a phase frequency detector (PFD) and correction circuit configured to, in response to the detected disturbance event, monitor for a plurality of measured crossing events of the MEMS oscillating structure oscillating about the rotation axis, generate a first compensation signal based on at least a first measured crossing event and a second measured crossing event to correct a frequency of the MEMS oscillating structure, and generate a second compensation signal based on a third measured crossing event to correct a phase of the MEMS oscillating structure.
TIME-TO-DIGITAL CONVERTER AND DIGITAL PHASE-LOCKED LOOP CIRCUIT COMPRISING THE SAME
Provided is a time-to-digital converter, comprising a phase frequency detector configured to receive a phase-locked loop input clock and a feedback clock, a ring oscillator configured to perform oscillation with multi-phase clocks of a first period, a counter array configured to count the number of oscillations in which the ring oscillator oscillates in a first period by the number of positive integers during the first pulse width, a multiplexer configured to divide the first period into a plurality of zones using edge information of the multi-phase clocks of the ring oscillator, and selects and outputs voltage information of a plurality of neighboring phase clocks included in a first zone from the plurality of zones, an analog-to-digital converter, a calibrator, and a first adder, wherein the calibrator comprises, an offset lookup table generation circuit, a gain-corrected analog-to-digital conversion output generator, and a second adder.
Hybrid Analog/Digital Phase Locked Loop with Fast Frequency Changes
A hybrid Phase Locked Loop, PLL (10, 34A, 34B, 38) employs an analog control loop during a first period of operation, such as steady-state operation, to achieve a simple design, stable operation at very high frequency, and low phase noise. During a second period of operation, such as frequency changes, a digital control loop takes over. Under digital control, charge pump (14) inputs are forced to be at or near 100% duty cycle for maximum loop filter (16) charging and fast, linear frequency change. The digital control loop monitors when the target frequency is reached, and exits the second period of operation with the proper feedback signal phase. The digital control loop can operate in two control modes. In a first mode, the phase of the divided VCO output signal is synchronized with the phase of a periodic reference signal throughout the frequency change. In a second mode, the frequency and phase are controlled in separate steps, by controlling the integer and fractional parts of delta-sigma generated division number. Three embodiments are disclosed. In a first embodiment, a switch substitutes constant charge pump (14) inputs for the outputs of a phase frequency detector, PFD (12) to maximize the loop filter (16) current. In a second embodiment, one pulse of one of the periodic signals is suppressed, forcing the PFD (12) to output charge pump input signals at near 100% duty cycle. In a third embodiment, all the cycles of one of the periodic signals are suppressed, forcing PFD (12) output signals to 100% duty cycle.
Multi-channel high-speed converter clock synchronization with autonomous coherent deterministic latency
A system and corresponding method that achieves coherency and deterministic latency (CDL) autonomously upon power on is disclosed. The system, for example, a multi-channel RF system, may require CDL with respect to the digital-to-analog converters (DACs) and analog-to-digital converters (ADCs) assigned to the channels in the system. CDL is achieved through a timed combination of external reference and synchronization signals, resetting and disabling of various clock dividers, and enabling clock generation. In addition to synchronizing all of the clocks, the data acquisition sequence must be synchronized across all of the channels, whether they are on chips, cards, or chassis. Data acquisition synchronization may be implemented using an initiator/target or a wired OR mode configuration.