Patent classifications
H03L7/00
Method for correcting 1 pulse per second signal and timing receiver
The disclosure provides a method for correcting a 1 pulse per second (1PPS) signal and a timing receiver. In the embodiments of the disclosure, the proposed method allows the timing receiver to provide a corrected 1PPS signal with better quality to back-end slave devices, thereby ensuring that the synchronization effect of the slave devices is not overly affected by jitter in a single 1PPS signal.
INTEGRATED CIRCUIT COMPRISING CIRCUITRY TO DETERMINE SETTINGS FOR AN INJECTION-LOCKED OSCILLATOR
Embodiments of an integrated circuit (IC) comprising circuitry to determine settings for an injection-locked oscillator (ILO) are described. In some embodiments, an injection signal is generated based on a first clock edge of a reference clock signal, and is injected into an ILO. Next, one or more output signals of the ILO are sampled based on a second clock edge of the reference clock signal, and settings for the ILO are determined based on the samples. In some embodiments, a sequence of two or more time-to-digital (TDC) codes is generated based on a reference clock signal and a free-running ILO. In some embodiments, the TDC circuitry that is already present in a delay-locked loop is reused for determining the sequence of two or more TDC codes. The ILO settings can then be determined based on the sequence of two or more
TEMPERATURE-COMPENSATED CRYSTAL OSCILLATOR BASED ON ANALOG CIRCUIT
Disclosed is a temperature-compensated crystal oscillator based on analog circuit; a closed-loop compensation architecture determines the temperature compensation of a crystal oscillator. The power splitter divides the VCXO's current output signal with frequency f=f.sub.0+Δf into two signals, one signal to output of the TCXO and the other signal is sent to an analog frequency-voltage conversion circuit. According to the frequency of the VCXO's current output signal, the analog frequency-voltage conversion circuit produces a voltage signal V(T), which corresponds to current ambient temperature. The difference between V(T) and a reference voltage signal V.sub.ref is produced and amplified to obtain a compensation voltage signal ΔV through a voltage matching circuit. ΔV is smoothed by a filter, then sent to the voltage control terminal of the VCXO to make the VCXO generate a stable signal with desired frequency f.sub.0, to compensate the frequency of the VCXO's output signal when the ambient temperature is changed.
Variable capacitance circuit for phase locked loops
A variable capacitance circuit may operate a Metal Oxide Semiconductor (MOS) transistor or other semiconductor device to switch a capacitor in and out. Several circuits may be combined in a parallel network having offset bias voltages, such that the combined network may produce a variable capacitance over a large voltage range. The variable capacitance circuit may be incorporated into a phase locked loop (PLL) circuit where similar devices may be configured to produce a voltage reference as part of the PLL circuitry. Such a circuit may be immune to temperature, process, or voltage variances, since the current pulse magnitude times the low pass filter resistance times the sensitivity of a controlled voltage oscillator can be held constant.
METHOD FOR PERFORMING DIVIDED-CLOCK PHASE SYNCHRONIZATION IN MULTI-DIVIDED-CLOCK SYSTEM, SYNCHRONIZATION CONTROL CIRCUIT, SYNCHRONIZATION CONTROL SUB-CIRCUIT, AND ELECTRONIC DEVICE
A method for performing divided-clock phase synchronization in a multi-divided-clock system, an associated synchronization control circuit, an associated synchronization control sub-circuit and an associated electronic device are provided. The method may include: performing frequency division operations according to a source clock to generate a first divided clock and a second divided clock; performing phase relationship detection on the first divided clock according to the second divided clock to generate a phase relationship detection result signal; performing a logic operation on a first phase selection result output signal and the phase relationship detection result signal to generate a second phase selection result output signal; and outputting one of the second divided clock and an inverted signal of the second divided clock according to the second phase selection result output signal, for further use in a physical layer circuit.
METHOD FOR PERFORMING DIVIDED-CLOCK PHASE SYNCHRONIZATION IN MULTI-DIVIDED-CLOCK SYSTEM, SYNCHRONIZATION CONTROL CIRCUIT, SYNCHRONIZATION CONTROL SUB-CIRCUIT, AND ELECTRONIC DEVICE
A method for performing divided-clock phase synchronization in a multi-divided-clock system, an associated synchronization control circuit, an associated synchronization control sub-circuit and an associated electronic device are provided. The method may include: performing frequency division operations according to a source clock to generate a first divided clock and a second divided clock; performing phase relationship detection on the first divided clock according to the second divided clock to generate a phase relationship detection result signal; performing a logic operation on a first phase selection result output signal and the phase relationship detection result signal to generate a second phase selection result output signal; and outputting one of the second divided clock and an inverted signal of the second divided clock according to the second phase selection result output signal, for further use in a physical layer circuit.
ELECTRICAL CIRCUIT
An electrical circuit, having: an oscillating element configured to provide a clock signal; and a clock synchronization unit configured to adapt the clock signal based on a reference signal; wherein the clock synchronization unit is configured to extract from an alternating signal the reference signal.
ELECTRICAL CIRCUIT
An electrical circuit, having: an oscillating element configured to provide a clock signal; and a clock synchronization unit configured to adapt the clock signal based on a reference signal; wherein the clock synchronization unit is configured to extract from an alternating signal the reference signal.
Clock and data recovery for multi-phase, multi-level encoding
An apparatus has a plurality of multi-level comparison circuits, each coupled to a pair of wires in a three-wire communication link, a plurality of first-level clock recovery circuits and a second-level clock recovery circuit. Each multi-level comparison circuit provides a multibit signal as an output. Each first-level clock recovery circuit includes a plurality of first-level flipflops clocked by transitions in a multibit signal received from one multi-level comparison circuit of the plurality of multi-level comparison circuits, and a first delay circuit that delays an output of the each first-level clock recovery circuit to provide a first reset signal that resets the each first-level clock recovery circuit. The second-level clock recovery circuit includes a second-level flipflop clocked by transitions in the outputs of the plurality of first-level clock recovery circuits, and a second delay circuit that delays an output of the second-level clock recovery circuit to provide a second reset signal to the second-level flipflop.
SEMICONDUCTOR INTEGRATED CIRCUIT, SEMICONDUCTOR STORAGE DEVICE, MEMORY SYSTEM, AND FREQUENCY GENERATION METHOD
A semiconductor integrated circuit includes a first oscillator configured to generate a first signal with a first frequency based on a control signal and output the first signal to a path. The semiconductor integrated circuit includes a control signal generation circuit operatively coupled to the first oscillator via the path, and configured to receive the first signal from the first oscillator via the path and generate the control signal. The semiconductor integrated circuit includes a second oscillator configured to generate a second signal with a second frequency based on the control signal and output the second signal to an output terminal outside the path.