63 results about "RC oscillator" patented technology

The invention discloses a method for eliminating interference of isolator chip radiation on a radio frequency system, which can measure the frequency of a low-frequency RC oscillator in a chip wafer test stage or a packaged finished product test stage, flexibly burn a corresponding frequency control signal of a storage unit according to the requirement of a client product communication system, and improve the reliability of the radio frequency system. Therefore, the local frequency and the harmonic frequency of the isolator chip are adjusted, so that the isolator chip can avoid the communication frequency band of a client. According to the method, a low-temperature-drift RC oscillation circuit is combined with a frequency-locked loop technology, and it is guaranteed that the frequency deviation of a local oscillation signal is controlled within 3% in different process deviations and a full-temperature range. Besides, the frequency of the high-frequency oscillator is accurately adjusted until the frequency is close to the target frequency, and the configuration parameters are stored in the nonvolatile storage module, so that the isolator chip does not interfere with other communication systems in the actual working process, and the stability and the reliability of the whole communication system are improved.

The invention belongs to the technical field of integrated circuits, and particularly relates to a high-precision RC oscillator circuit. According to the invention, the influence of the delay introduced by the limited bandwidth of the comparator and the delay of a logic circuit is eliminated from the circuit structure, and high frequency precision and stability can be obtained: by designing the adjustable capacitor, the actual output clock frequency can be discretely adjusted; by designing the temperature-adjustable resistor, the temperature coefficient of the resistor can be flexibly adjusted, so that the variation of the output clock frequency along with the temperature can be ignored, and the stability of the output clock frequency is improved. The system is especially suitable for some low-cost and low-power-consumption application scenes, and has the characteristics of low cost, high integration level and good stability.

The invention provides a design method and system of a high-speed RC clock system. The system comprises a high-speed RC oscillator, a reference clock module, a clock calibration module, a trigger module and a state machine module. The method comprises the following steps of: controlling a calibration process through a state machine module, counting a high-frequency clock signal by taking a theoretical count value as a reference after a clock calibration module is triggered, judging whether the frequency has deviation or not and the direction of the deviation according to a counting result, performing stepping adjustment on a calibration value, and performing frequency adjustment on a high-speed RC oscillator. And circularly executing the calibration step until the counting result falls into an allowable error range. A phase-locked loop circuit does not need to be additionally arranged, high and low temperature calibration in the production stage does not need to be introduced, the chip design complexity, the manufacturing cost and the production test cost can be effectively reduced, meanwhile, high precision and stability of clock signals are ensured, and output of a low-cost, high-frequency and high-precision RC clock is achieved.

The invention relates to the technical field of electronic circuits, and provides a temperature compensation circuit and an RC oscillator, the temperature compensation circuit comprises a voltage control module and a clock signal generation module, the voltage control module is used for outputting a control signal to the clock signal generation module according to the environment temperature; wherein the frequency of the control signal is related to the temperature of the environment; the clock signal generation module is used for generating a clock signal according to the control signal; wherein the duty ratio of the clock signal is related to the frequency of the control signal. According to the temperature compensation circuit, the clock signal with the duty ratio changing along with the environment temperature can be generated, and the precision of an RC oscillator and other circuits under the influence of the temperature is improved.

The present invention discloses a method for eliminating the interference of isolator chip radiation on the radio frequency system. The method can measure the frequency of the low-frequency RC oscillator during the chip wafer test or the finished product test stage after packaging, and flexibly burn the corresponding frequency control signal of the storage unit according to the needs of the customer's product communication system to adjust the local oscillator frequency and its harmonic frequency of the isolator chip to avoid the customer's communication frequency band. This method uses a low-temperature drift RC oscillator circuit combined with frequency-locked loop technology to ensure that the frequency deviation of the local oscillator signal is controlled within 3% within different process deviations and the full temperature range. In addition, by accurately adjusting the frequency of the high-frequency oscillator until it is close to the target frequency, and storing these configuration parameters in a non-volatile storage module, the isolator chip will not interfere with other communication systems during actual operation, thereby improving the stability and reliability of the entire communication system.

The present application belongs to the field of analog integrated circuit, and particularly relates to an RC oscillator without starting circuit. The present application uses Schmitt trigger as the comparator in the RC oscillator, and uses the hysteresis effect and positive feedback characteristics of the Schmitt trigger to reduce the influence of kickback noise. Meanwhile, a reset port is added to the Schmitt trigger, so that the working state of the input end of the RS flip-flop is simultaneously low when the circuit starts; and the two output signals of the RS flip-flop are respectively applied to the reset ends of the two Schmitt triggers through the delay control module, so that the reset signal of the Schmitt trigger cannot control the output result in advance before the input signal changes, and the timing error is avoided. The present application effectively solves the problems of the existing RC oscillator, such as the need of starting circuit and high noise.

The application discloses a low-temperature-drift calibratable RC relaxation oscillator circuit, which comprises an oscillator core module, a voltage reference module, a voltage-to-current conversion module and a current DAC module, wherein the voltage reference module generates a reference voltage VREF; the voltage-to-current conversion module converts the obtained reference voltage into a reference current IREF; the current DAC module provides the adjusted currents I1, I2 and I3 to the oscillator core module, and the non-linear influence of process corners on the output frequency of the RC oscillator is reduced by adjusting the currents; the oscillator core module finally generates a clock signal CLK, and the problems that the comparator delay and the comparator offset are greatly changed with temperature are reduced by using the current self-compensation technology and the chopping technology, and thus the performance of the oscillator output frequency is improved. Compared with the traditional RC relaxation oscillator, the application reduces the temperature drift of the output frequency and improves the accuracy of the frequency by structural optimization and technical innovation.

This disclosure provides systems, devices, apparatus, and methods, including computer programs encoded on storage media, for ESYNC hybrid mode. A processor determines that an AP is to transition from a first power mode to a second power mode based on a change in a refresh rate of a display panel. The processor switches, based on the determination and during a transmission of a continuous external HSYNC signal, a source of a clock associated with the external HSYNC signal from being generated via PLL clock to being generated via an RC oscillator clock.

This application discloses a low-power temperature-compensated RC oscillator, comprising a low-voltage linear buffer, an RC core circuit, a comparator, a Schmitt trigger, a non-overlapping clock generator, and a level shifter. The low-voltage linear buffer uses intrinsic transistors to reduce operating voltage and power consumption; the RC core circuit employs temperature compensation technology, including a series low-temperature drift resistor and a temperature-dependent current source, causing the equivalent resistance to increase with temperature; the comparator compares a triangular wave signal with a reference voltage and outputs a reference clock; the Schmitt trigger filters out clock glitches; the non-overlapping clock generator generates a two-phase clock with dead time to control charging and discharging; and the level shifter converts the low-voltage domain clock to the high-voltage domain. This oscillator eliminates the influence of comparator offset voltage through two-phase switching control and employs low-voltage and temperature compensation technology to achieve a high-precision, low-temperature drift reference frequency in a small area with low power consumption, making it suitable for compact sensing and measurement systems.

The present disclosure relates to a starting method and starting circuit of a crystal oscillator, and belongs to the technical field of electronic circuits, which can realize fast starting of the crystal oscillator. The starting method of the crystal oscillator comprises: receiving a crystal oscillator starting signal, wherein the crystal oscillator starting signal is used to indicate that the crystal oscillator needs to be started; in response to the crystal oscillator starting signal, starting an RC oscillator, and selecting, by an injection selector, a signal generated by the RC oscillator as a first injection signal to be injected into the crystal oscillator; starting a phase-locked loop to make the phase-locked loop work under the driving of a square wave signal output by the crystal oscillator, wherein the square wave signal is generated by the crystal oscillator based on the first injection signal; after the phase-locked loop is locked, selecting, by the injection selector, a signal generated by the phase-locked loop as a second injection signal to be injected into the crystal oscillator.

Embodiments of the present disclosure disclose an RC oscillator, an electronic device and a chip. The RC oscillator comprises: a current generation circuit comprising a transistor and a resistor, configured to output a bias current according to a power supply voltage, an inter-electrode voltage of the transistor and a resistance value of the resistor; a charging and discharging control circuit comprising a capacitor and connected to the current generation circuit, configured to charge the capacitor by the power supply voltage or discharge the capacitor by the bias current; and a logic control circuit connected to the current generation circuit and the charging and discharging control circuit, configured to compare a capacitor voltage of the capacitor with a voltage threshold determined based on the inter-electrode voltage, and control the charging and discharging control circuit to switch to a first stage or a second stage. The present disclosure does not need to design a complex voltage reference and current reference circuit, greatly simplifies the overall circuit structure, and saves chip area and power consumption.

An RC oscillator circuit is provided. An output terminal of the first current source unit is connected to the oscillation resistor and non-inverting inputs of the comparators, and the other end of the oscillation resistor is grounded. The second current source unit has two output terminals. Sources of the two oscillation MOS transistors are grounded, drains of the oscillation MOS transistors are connected to a corresponding oscillation capacitor, and gates of the oscillation MOS transistors are connected to an output of the RS latch. The first current source unit includes four MOS transistors and a first resistor. The frequency of the output clock signal is unaffected by substrate bias effects of MOS transistors and resistor variations, thereby ensuring a highly stable output frequency with minimal deviation, and greatly improving the reliability and stability of the RC oscillator circuit.

The invention discloses a low-power-consumption temperature compensation RC oscillator which is composed of a low-voltage linear buffer, an RC core circuit, a comparator, a Schmitt trigger, a non-overlapping clock generator and a level shifter. The low-voltage linear buffer adopts an intrinsic transistor to reduce working voltage and power consumption; the RC core circuit adopts a temperature compensation technology and comprises a series low-temperature drift resistor and a temperature positive correlation current source, so that equivalent resistance is increased along with temperature; the comparator compares the triangular wave signal with a reference voltage and outputs a reference clock; the Schmitt trigger filters clock burrs; the non-overlapping clock generator generates a two-phase clock with dead time to control charging and discharging; the level shifter converts the low voltage domain clock to the high voltage domain. The oscillator eliminates the influence of offset voltage of the comparator through two-phase switch control, adopts a low-voltage and temperature compensation technology, realizes high-precision and low-temperature-drift reference frequency under the conditions of small area and low power consumption, and is suitable for a compact sensing measurement system.

The invention provides a terminal, a clock synchronization circuit, system and method and a storage medium. The clock synchronization circuit comprises a crystal oscillator which is started to provide a first clock signal in a terminal working state; the RC oscillator is started to provide a second clock signal different from the first clock signal when the terminal is in a dormant state; the timer is connected with the RC oscillator and starts timing based on a second clock signal when the terminal is in a dormant state; when the timing time reaches the preset time, the terminal is in a working state, and the crystal oscillator starts the RC oscillator to keep starting; the calibrator is connected with the crystal oscillator and the RC oscillator, starts to detect the first clock signal and the second clock signal in a working dormant state and judges whether a preset condition is met or not, and if not, the second clock signal is calibrated based on the first clock signal; and the controller is connected with the crystal oscillator RC oscillator timer and the calibrator, controls the starting or closing of the crystal oscillator RC oscillator timer and the calibrator, and controls the terminal to switch between a working state and a dormant state, so that the balance of low cost, low power consumption and clock accuracy is realized.

The present invention relates to a low-power RC oscillator applied to a temperature sensor. By means of capacitance multiplication technology and high-order temperature compensation technology, the oscillator reduces the layout area and the output frequency drift caused by temperature changes. In addition, the present invention reduces the influence of non-linear factors caused by the manufacturing process in mass production of the oscillator through multi-range frequency trimming technology. Through structural optimization and technological innovation, the invention can achieve a highly stable effect at low power consumption and is applicable to temperature sensor systems.

The invention discloses a low-power-consumption low-temperature-drift high-frequency oscillator circuit capable of internally dividing frequency, and relates to the technical field of oscillators. The oscillator circuit comprises a digital power supply voltage generating circuit, a reference voltage generating circuit and an RC oscillator, the digital power supply voltage generating circuit is used for generating digital power supply voltage VDDD and inputting the digital power supply voltage VDDD to the RC oscillator, and the reference voltage generating circuit is used for outputting reference voltage VREF and bias current IB, the reference voltage VREF and the bias current IB are input to the RC oscillator, and the RC oscillator is used for outputting frequency under the action of the digital power supply voltage generating circuit and the reference voltage generating circuit. The oscillator circuit can accurately carry out frequency division, and the output frequency is stable.

The utility model relates to the technical field of sampling and metering circuits, in particular to a control circuit for controlling an asynchronous transceiver based on GPIO (General Purpose Input / Output) chip selection signals. The circuit design comprises a voltage sampling circuit, a current sampling circuit, an optocoupler isolation communication circuit and a V9240 metering chip circuit, the working state of a metering chip is flexibly controlled through GPIO chip selection signals, and accurate electric energy metering is achieved. A voltage sampling part of the circuit adopts a divider resistor and a sampling capacitor, and a current sampling part collects signals by using a manganese-copper diverter and parallel resistors and capacitors. The optical coupler isolation communication circuit provides safety and isolation protection for data transmission. An RC oscillator is integrated in the V9240 metering chip, the requirement for an external crystal oscillator is eliminated, the circuit design is simplified, and the cost is reduced. The control circuit has the characteristics of low power consumption, high sensitivity and capability of adapting to different power grid frequencies, and is suitable for application occasions sensitive to power consumption, such as an intelligent electric meter and a remote monitoring system.

This disclosure provides systems, devices, apparatus, and methods, including computer programs encoded on storage media, for ESYNC hybrid mode. A processor determines that an AP is to transition from a first power mode to a second power mode based on a change in a refresh rate of a display panel. The processor switches, based on the determination and during a transmission of a continuous external HSYNC signal, a source of a clock associated with the external HSYNC signal from being generated via PLL clock to being generated via an RC oscillator clock.

The invention discloses a low-power-consumption RC oscillator. The low-power-consumption RC oscillator comprises a starting circuit, a current source circuit and a core oscillation circuit. The starting circuit is responsible for enabling the whole circuit to successfully reach a designed working point, and is turned off after being started; the current source circuit is responsible for generating a PTAT current; the core oscillation circuit is responsible for generating square wave oscillation. By adopting an AVDD / AVSS dual-power supply architecture and a multi-path current mirror structure, the technical bottlenecks of starting delay, temperature drift, power consumption efficiency compromise and the like of a traditional RC oscillator are effectively solved through the collaborative optimization design of the core oscillation circuit and the buffer output stage while the oscillation frequency stability is ensured, and the stability of the RC oscillator is improved. And a novel solution is provided for the power management module of a miniaturized electronic system.

A system with a low-drift on-chip (LD-RC) oscillator with lowered sensitivity to Random Telegraph Noise when generating a current (Id) for the LD-RC oscillator. A control resistor (R) is connected through an intermediary arrangement to one of a first MOS transistor (M1) or of a second MOS transistor (M2) between two terminals of a supply voltage source (Vdd). The gate of the first MOS transistor (M1) is connected to the gate of the second MOS transistor (M2), whereas the source of the first MOS transistor (M1) and the source of the second MOS transistor (M2) are connected to one terminal of the supply voltage source (Vdd), the control resistor (R) being connected to the other opposite terminal of the supply voltage source.

The invention discloses an RC oscillator circuit, relates to the technical field of integrated circuits, and provides the RC oscillator circuit for solving the problem that an existing RC oscillator cannot flexibly adjust the duty ratio of output square wave signals, and the RC oscillator circuit is characterized in that an adjustable capacitor is connected to the output end of a square wave signal generation module through a first switch; when a square wave signal output by the square wave signal generation module is in a certain level stage, the first switch is closed to enable the adjustable capacitor to be connected to the output end of the square wave signal generation module, and the connected adjustable capacitor enables the square wave signal to generate time delay when the square wave signal is turned from the current level to another level; due to the fact that the capacitance value of the adjustable capacitor is adjustable, time delay generated when the level of the square wave signal is overturned is adjustable, and the effect that the duty ratio of the square wave signal can be freely adjusted is achieved.

The invention relates to the technical field of ultrasonic motor driving, and discloses a reverse-phase double-path bias ultrasonic motor driving system based on RC oscillation, which comprises an RC oscillator module, a reverse-phase double-path bias circuit module, a control module, a self-adaptive filter module, a temperature sensor and an environment monitoring module, the invention also provides a control method of the reverse-phase double-path bias ultrasonic motor drive based on RC oscillation, and the method comprises the following steps: generating a high-frequency signal by using the RC oscillator, forming oscillation frequency through the combination of a resistor and a capacitor, and carrying out the temperature compensation of the RC oscillator module based on the environment temperature; complementary signals are generated through the reverse-phase double-path bias circuit module to drive the positive direction and the negative direction of the ultrasonic motor. By adopting the technical scheme of combining the RC oscillator and a temperature compensation mechanism, the influence of temperature change on frequency is compensated by adjusting resistance and capacitance values in real time, and the stability of the system at different environment temperatures is ensured.

An embodiment of the present application discloses an RC oscillator that can employ a first amplifier and a second amplifier to amplify the difference between a first voltage and a second voltage. The first amplifier can include a first amplifier circuit and a second amplifier circuit. The first amplifier circuit and the second amplifier circuit can reuse the same voltage-to-current conversion circuit. The RC oscillator disclosed in the embodiment of the present application not only avoids noise introduced by the first amplifier but also reduces the internal noise of the RC oscillator, thereby reducing the jitter of the clock signal.

The invention provides a low-power RC oscillator circuit and a working method thereof. The low-power RC oscillator circuit comprises a chopper circuit, a path delay offset loop, a power supply structure and an RC circuit, the chopper circuit is connected with the path delay offset loop and the RC circuit and is used for eliminating the offset influence of the comparator; the path delay counteracting loop is also connected with the RC circuit and is used for extracting delay to counteract path delay; the power supply structure is used for supplying power to the chopper circuit, the path delay offset loop and the RC circuit; the RC circuit is used for generating an oscillation signal; therefore, the frequency precision of the circuit is improved, the performance of low voltage and low power consumption is realized, and a more stable clock signal is realized under the condition that the temperature and the power supply change.

The invention discloses a threshold switch memristor for image encryption and a true random number generator with the memristor, the memristor comprises a substrate, a bottom electrode, a first dielectric layer, a second dielectric layer, a third dielectric layer and a top electrode which are sequentially arranged from bottom to top, and the first dielectric layer and the third dielectric layer are made of starch. The true random number generator comprises an RC oscillator, a comparator and an FPGA, and in the RC oscillator, a resistor connected with a capacitor and an output end adopts a memristor. According to the memristor disclosed by the invention, the switching current, the threshold voltage, the high resistance state and the low resistance state have extremely high irregularity; the sequence generated by the true random number generator has stronger randomness.

The utility model discloses a novel high-voltage input cascade topology control application circuit, which comprises a first control chip, a second control chip and a synchronizing signal circuit, the working frequency of the first control chip is smaller than that of the second control chip, the second control chip is connected with the first control chip through the synchronizing signal circuit, and the synchronizing signal circuit is connected with the first control chip. And the second control chip controls the post-stage working frequency of the first control chip through the synchronous signal circuit. According to the utility model, the second control chip is added, the second control chip sets the post-stage working frequency required by the first control chip as the target working efficiency, the driving wave of the second control chip is differentiated into a 50nS pulse signal through the synchronizing signal circuit, and the 50nS pulse signal is sent to the RC oscillator in the first control chip; the RC oscillation circuit in the first control chip acts in advance, so that the pre-stage working frequency of the first control chip is equal to the post-stage working frequency of the first control chip, thereby reducing the switching loss of pre-stage power conversion, reducing the heating of a power supply and improving the efficiency of the power supply.

Disclosed is an RC oscillator comprising: a bias circuit, generating first and second bias currents, and outputting a charging current proportional to a total bias current that is the sum of the first and second bias currents, wherein the ratio of the first bias current to the second bias current has a positive temperature coefficient; and an oscillation circuit, for periodically charging a capacitor using the charging current output by the bias circuit, and using a voltage across a resistor through which the second bias current or a current proportional thereto flows as a reference voltage to compare with a charging voltage on the capacitor, so as to obtain a periodically oscillating clock signal. Thus, the present disclosure can compensate the positive temperature coefficient of the subsequent delay and realize the RC oscillator with low temperature drift by making the charging time of the capacitor have a negative temperature coefficient.

The application relates to low temperature drift low adjustment RC oscillator, relates to integrated circuit technology, and the application comprises reference source circuit, the reference source circuit comprises reference current signal output end and reference voltage output end, characterized by further comprising shared comparison circuit, first capacitive oscillator with discharge switch, second capacitive oscillator with discharge switch, first comparator, second comparator and RS trigger, the application offsets temperature changes of the reference current and the reference voltage, so that the output clock frequency of the oscillator circuit is basically not changed with temperature, the oscillator circuit structure is symmetrical, and the error caused by the comparator hysteresis to the clock frequency is eliminated.

This application discloses a real-time clock calibration method, apparatus, device, and medium, relating to the field of real-time clock calibration. Within a preset calibration time period, the frequency of an RC oscillator clock and the frequency of a quartz crystal oscillator clock are acquired, and the compensation bit number of the RC impedance control bit of the RC oscillator clock is generated to physically compensate the RC oscillator clock. The error compensation value of the physically compensated RC oscillator clock is obtained; and the time of the RC oscillator clock is adjusted according to the error compensation value. Therefore, the above scheme generates the compensation bit number of the RC impedance control bit of the RC oscillator clock by using the frequencies of the two clocks in the system, thereby adjusting the RC impedance control bit and achieving physical compensation of the RC oscillator clock. Simultaneously, the error compensation value of the physically compensated RC oscillator clock is obtained, and the remaining error of the RC oscillator clock is calibrated, ultimately achieving accurate output of the RC oscillator clock under low power consumption.

The application discloses a frequency calibration method for an LED driving chip, an LED driving chip and an LED lamp, and is applied to the LED driving chip connected with an external host through an I2C bus. The method comprises the following steps: monitoring a serial clock line in real time during normal I2C communication, and generating a calibration window after detecting a self-calibration enabling signal; counting the output pulse of a built-in RC oscillator in the calibration window, and obtaining a single counting value; performing average operation on the single counting values of multiple different calibration windows, and generating a sampling average value; comparing the sampling average value with a pre-stored standard counting value to obtain a frequency error value; and adjusting the tuning control parameter of the RC oscillator to correct the output frequency according to the frequency error value. The application uses the SCL clock signal in the I2C communication as a calibration reference, does not need to add a hardware pin, does not need the host to participate in operation, does not interrupt normal display business, and independently completes dynamic and real-time calibration of the frequency of the RC oscillator in the normal working process of the chip.