25 results about "Relaxation oscillator" patented technology

The invention discloses a hardware circuit for realizing limp control of a steering lamp function, and belongs to the technical field of automobile body control modules. According to the method, when the main control module of the BCM fails, the steering lamp limping control function is automatically started through a hardware circuit, it is ensured that the flickering function of the steering lamp or the danger warning lamp can still be achieved under the condition that the main control module of the vehicle fails, and the driving safety is improved. The hardware circuit comprises a main control module, an LIMPHOME logic judgment circuit, a relaxation oscillator circuit, a high-side driving circuit, a steering lamp switch and a steering lamp. The LIMPHOME logic judgment circuit detects a PWM output signal of the main control module through the capacitor charging and discharging circuit and judges whether the main control module works normally or not; when the master control module fails, the relaxation oscillator circuit generates a PWM control signal based on the turn light switch signal and the LIMPHOME logic output; and the high-side driving circuit drives the steering lamp to flicker according to the PWM signal. The method is realized through pure hardware, is low in cost, quick in response and high in reliability, and is suitable for various vehicle BCM systems.

A voltage mode relaxation oscillator includes a bandgap reference (BGR) circuit configured to generate a BGR voltage that does not depend on temperature and a BGR current that depends on temperature; a control voltage generating circuit configured to generate a control voltage that does not depend on temperature based on the BGR voltage; a reference current generating circuit configured to generate a reference current that does not depend on temperate based on the BGR current; and an oscillator circuit configured to generate a clock signal that does not depend on temperature based on the control voltage and the reference current.

A relaxation oscillator includes first to the sixth transistor, a resistor, a capacitor, an inverter, a pulse generator, and first to the third switch. The resistor is coupled between the third source and the third gate of the third transistor. The capacitor is coupled between the fourth source and the fourth gate of the fourth transistor. The input terminal of the inverter is coupled to the sixth drain of the sixth transistor. The pulse generator generates a pulse signal. The first switch is coupled between the inverter and a first reference voltage. The second switch is coupled between the inverter and the fifth transistor. The third switch is coupled between the fourth transistor and a second reference voltage. The first to third switches are turned on or off according to the pulse signal.

This invention discloses a frequency self-calibration circuit based on a voltage-mode RC relaxation oscillator, belonging to the field of integrated circuits. By storing time errors, it performs negative feedback control on the trigger times of the rising and falling edges of the output clock signal, automatically calibrating the output signal frequency. Furthermore, it achieves DC deviation elimination in the self-calibrating operational amplifier, significantly reducing offset voltage. This invention solves the problem of unstable signal output frequency in voltage-mode RC relaxation oscillator circuits due to changes in ambient temperature. It can be applied to Delta-Sigma ADC circuits, filter circuits, phase-locked loop circuits, etc., improving resistance to ambient temperature changes and compensating for comparator switching delays. t d This improves the linearity of the clock oscillator, enhances circuit reliability, and meets the accuracy requirements of highly integrated signal chain acquisition systems.

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 invention relates to the field of circuit hardening technology, and provides a voltage-controlled oscillator (VCO) circuit and phase-locked loop (PLL) circuit that are resistant to single-event transients. Addressing the issue that traditional three-mode relaxation oscillator (VCO) circuits are unsuitable for low-voltage conditions, especially when the power supply voltage drops to around 0.8V, this invention employs six oscillation branches coupled into three large oscillation loop circuits to improve loop gain. Furthermore, by combining bias circuits, comparators, and voting circuits for each path, the problem of increasing nonlinearity is avoided. This achieves a combination of large oscillation loops, bias circuits, and a three-mode VCO architecture, resulting in a VCO circuit that maintains high-frequency stable operation under ultra-low voltage conditions such as 0.8V, thus achieving a single-event transient resistance effect, especially at low voltages of 0.8V.

The invention provides a high-precision low-temperature-drift relaxation oscillation system with a symmetrical double-path architecture and a calibration method thereof. The system comprises a symmetric double-channel relaxation oscillator core framework, a fine adjustment circuit, a coarse adjustment circuit and a band-gap reference source module. The method comprises the following steps: S1, acquiring initial working parameters of a relaxation oscillator by a system, and determining an initial frequency value of the oscillator; s2, executing coarse adjustment calibration by a coarse adjustment circuit, and adjusting the frequency of the oscillator to be within a first preset range of a target frequency value; s3, the fine adjustment circuit executes fine adjustment calibration, and further adjusts the frequency of the oscillator to be within a second preset range of the target frequency value; s4, the band-gap reference source module executes temperature compensation calibration; s5, the system adjusts the proportion of the charging current and the discharging current, and duty ratio adjustment is executed; s6, the system executes frequency stability verification; and S7, generating a final calibration configuration and storing the final calibration configuration for long-term use of the oscillator. The invention is applied to the technical field of integrated circuits.

Relaxation oscillator comprising: a current source (11; 40; 50) for providing a charging current, a capacitor arrangement (12; 41; 51, 52) coupled to the current source (11; 40; 50), wherein the current source is configured to charge the capacitor arrangement (12; 41; 51, 52) during an operating period (Tideal), a detection arrangement (13; 43, 44, 45, 46) configured to detect when a voltage across the capacitor arrangement (12; 41; 51, 52) reaches a threshold voltage, and to discharge the capacitor arrangement (12; 41; 51, 52) in response to reaching the threshold voltage during the operating period (Tideal), wherein the charging and discharging of the capacitor arrangement (12; 41; 51, 52) in each operating period occurs exactly once, and a measuring device (14; 47, 48; 53) is set up to provide a measure of a propagation delay of the detection device (13;43, 44, 45, 46) to measure, wherein the relaxation oscillator is configured to increase a charging rate of the capacitor device (12; 41; 51, 52) for a duration based on the measure of the propagation delay, wherein the relaxation oscillator is configured to end the operating period (Tideal) following discharge and to begin a next operating period, at the beginning of which the capacitor device (12; 41; 51, 52) is recharged.;

The application discloses a compact time domain reflectometer probe based on high-speed logic gates, which comprises a power filter module, an ultrafast edge pulse generation module, an impedance matching driving module and a signal separation and test port module, the power filter module supplies power for the ultrafast edge pulse generation module and the impedance matching driving module, the ultrafast edge pulse generation module is a relaxation oscillator, the relaxation oscillator outputs a square wave signal to the impedance matching driving module, the impedance matching driving module inputs the square wave signal after impedance matching to the signal separation and test port module, and the signal separation and test port module comprises a triangular resistance distribution network formed by three resistors. Compared with the existing simple TDR scheme or expensive professional equipment, the time domain reflectometer probe disclosed by the application has the advantages of high resolution, excellent impedance matching, compact structure, low cost and the like.

The utility model relates to a relaxation oscillator. Comprising a resistor, a capacitor, a voltage comparator, a low-pass filter and a temperature compensation circuit, the resistor and the capacitor are combined to form an RC charging circuit which is responsible for generating a gradually changing voltage. The voltage can generate charging and discharging fluctuations at the two ends of the capacitor as time goes on, and then periodic changes are provided for the oscillator. And the voltage comparator is used for monitoring the voltage on the capacitor. And two input ends of the comparator are respectively connected to a connection point of the capacitor and a reference voltage Vref. When the voltage at the two ends of the capacitor exceeds or is lower than the reference voltage Vref, the comparator outputs a digital signal (high or low) so as to trigger the oscillation behavior. And the output signal enters the low-pass filter after passing through the voltage comparator. The low-pass filter is used for smoothing signals, reducing high-frequency noise and stabilizing signal output.

The application discloses a relaxation oscillator based on a switched capacitor array and a peak feedback structure and a stabilizing method, the oscillator comprising a reference source, a switched capacitor array, a peak voltage feedback module, a comparator and a digital logic circuit, the switched capacitor array comprising two symmetric charge-discharge branches, each branch having a main charging capacitor and a tracking holding capacitor, and the peak voltage feedback module being composed of an operational amplifier, a feedback capacitor and a sampling switch. In operation, the capacitor voltage of one branch charged alternately is compared with a dynamic threshold, and the peak voltage on the tracking holding capacitor of the other branch is sampled to the feedback module at the switching moment, the comparator threshold is dynamically adjusted through the integral action, and finally the capacitor peak voltage is locked to the fixed reference voltage, so that the influence of non-ideal factors such as comparator delay on the oscillation period is systematically offset. The application also adopts a chopping comparator to eliminate the offset. The architecture significantly improves the stability of the oscillation frequency to the power supply voltage and temperature, and helps to realize low phase noise, and is suitable for high-precision on-chip clock sources.

A relaxation oscillator includes first to sixth transistors, a resistor, a capacitor, an inverter, a pulse generator, and first to third switches. The resistor is coupled between a third source and a third gate of the third transistor. The capacitor is coupled between a fourth source and a fourth gate of the fourth transistor. The input end of the phase inverter is coupled with the sixth drain electrode of the sixth transistor. The pulse generator generates a pulse signal. The first switch is coupled between the inverter and a first reference voltage. The second switch is coupled between the inverter and the fifth transistor. The third switch is coupled between the fourth transistor and a second reference voltage. The first to third switches are switched on or switched off according to the pulse signal.

This invention discloses a fast-start relaxation oscillator and electronic device, relating to the field of oscillator technology. The circuit includes: a constant current source; a digital adjustment module for adjusting the current of the constant current source; a first charging circuit, with its input connected to the output of the digital adjustment module; a second charging circuit connected in parallel with the first charging circuit; a first comparator, with its positive input connected to the positive terminal of a first capacitor and its inverting input connected to a reference voltage; a second comparator, with its positive input connected to the positive terminal of a second capacitor and its inverting input connected to the reference voltage; and a transistor-level cross-coupled latch, with its input connected to the outputs of the first and second comparators, and its output connected to the controlled terminals of the first and second charging circuits. This circuit can eliminate the reset dead time problem through the alternating charging of the two capacitors.

The application provides a relaxation oscillator circuit and a control method, an integrated chip and an electronic device. A first control unit of the relaxation oscillator circuit is configured to perform digital logic determination on a wake-up indication signal and output a first control signal; a second control unit is configured to output a second control signal based on the wake-up indication signal; in a low-frequency mode and when the first control signal is a valid signal, the relaxation oscillator unit switches to a normal working high-frequency mode; in the low-frequency mode and when the second control signal is a valid signal and the first control signal is an invalid signal, the relaxation oscillator unit switches to a wake-up detection high-frequency mode; and in the wake-up detection high-frequency mode, if the first control signal output is a valid signal, the relaxation oscillator unit switches to the normal working high-frequency mode. The relaxation oscillator unit can be switched to the wake-up detection high-frequency mode or the working high-frequency mode under different conditions, which is beneficial to reducing power consumption and improving overall processing speed.

The application discloses a high-precision relaxation oscillator with fast starting, comprising: a reference voltage generating module for generating a first and a second reference voltage; a capacitor charging and discharging module for generating a periodically changing first and a second real-time voltage; a bypass reference voltage generating module electrically connected with the reference voltage generating module, for generating a bypass reference voltage based on the second reference voltage; a charging and discharging control module electrically connected with the reference voltage generating module and the capacitor charging and discharging module, for controlling the capacitor charging and discharging module to alternately charge and discharge based on the first reference voltage and the first and the second real-time voltage; and a bypass control module electrically connected with the reference voltage generating module and the bypass reference voltage generating module, for controlling the charging current multiple of the capacitor charging and discharging module based on the first reference voltage and the bypass reference voltage. The application can realize high-precision frequency output of the oscillator in a wide voltage and temperature range, and achieve a fast starting effect that is stable in the second cycle.

The invention provides a load protection circuit and method for a power supply module of medical equipment, and relates to the technical field of medical power distribution. One side of the energy absorption circuit is connected with the output direct current port, and the other side of the energy absorption circuit is connected with the input end of the medical device; the driving sub-circuit is electrically connected with the energy absorption circuit; the energy absorption main circuit comprises a voltage sampling unit, a comparison unit, a driving unit and a power switch unit; and the output end of the relaxation oscillator of the driving sub-circuit is connected with the control end of the driving unit in the energy absorption main circuit. The system has the advantages of extremely high reliability, long service life, ultra-fast response, active protection, strong energy absorption capability, excellent anti-interference performance and stability, and the intelligentization and manageability of the system are enhanced.

The invention discloses a relaxation oscillator, method and system capable of calibrating temperature and frequency simultaneously, the relaxation oscillator comprises a voltage average feedback VAF circuit, the voltage average feedback VAF circuit comprises an oscillation capacitor, a comparator, a latch and a voltage division network used for generating reference voltage Vref, and the voltage division network comprises a main voltage division branch and an auxiliary voltage division branch, the main reference voltage generation circuit is connected between power supply voltage and the ground, is used for generating main reference voltage and comprises a first-class resistor and a second-class resistor, the first-class resistor has a first temperature coefficient, and the second-class resistor has a second temperature coefficient; the first programmable adjusting unit is used for responding to a first digital control signal so as to adjust the effective resistance value of the first type of resistors; the second programmable adjusting unit is used for responding to the second digital control signal to adjust the effective capacitance value of the oscillation capacitor; according to the circuit and the method, the output frequency and the temperature coefficient of the oscillator can be independently, accurately, efficiently and simultaneously calibrated, and the product performance and the production yield are greatly improved.

This application relates to a relaxation oscillator and a method for stabilizing the frequency of the relaxation oscillator. The relaxation oscillator includes: a first RC network module comprising an RC network and a signal multiplexing unit with identical structures; the RC network receiving an external power supply signal and a clock signal output from a first clock feedback module, and outputting a first voltage signal pair and a second voltage signal pair respectively; the clock signal including a first clock signal and a second clock signal with opposite phases; the signal multiplexing unit selecting, based on the phase of the clock signal, a voltage pair with a higher common-mode voltage as a first target voltage signal pair and outputting it to the first clock feedback module; and the first clock feedback module comparing the amplitudes of the two voltage signals in the first target voltage signal pair with preset thresholds respectively, and outputting the first clock signal and the second clock signal to the first RC network module based on the comparison results. The frequency stability of the relaxation oscillator is improved by enhancing the RC network through asymmetric swing.

Embodiments herein describe relaxation oscillator circuits for physical unclonable function (PUF) circuits and / or for providing clocks to multiple dies. The relaxation oscillator circuit generates a clock having a frequency that is based in part on random process variations of the passive components of the relaxation oscillator circuit. The relaxation oscillator circuit may be distributed amongst multiple dies of an integrated circuit device, to incorporate additional sources of randomness / entropy, enhance security, to provide clocks to the multiple dies. The relaxation oscillator circuits include differential and single-ended relaxation oscillator circuits. Resistive and / or capacitive components may be configurable, which may be useful for testing purposes, altering PUF codes, and / or generating time-multiplexed clocks.

The invention provides an RC relaxation oscillator with temperature compensation and based on a voltage-controlled variable capacitor, and the oscillator comprises a main chip which comprises an RC relaxation oscillator and is used for generating a clock signal; the control module is used for collecting the temperature of the main body chip, obtaining a temperature sampling value, outputting an analog voltage according to the temperature sampling value, and coupling the analog voltage to the first end of the variable capacitor. The variable capacitor with temperature compensation and based on voltage control is adopted, the precision of frequency compensation can be improved to 0.1 Hz or lower, it is achieved that a quartz crystal oscillator is replaced by an all-silicon chip, expensive MEMS process devices are not needed, and cost is reduced; according to the variable capacitor structure with the temperature compensation function, the temperature drift value and the frequency precision index level are improved through temperature compensation, working is stable, meanwhile, the variable capacitor structure with the temperature compensation function can be suitable for any RC relaxation oscillator, the matching degree is high, and therefore large-scale mass production can be achieved on the premise that the product yield is guaranteed.

The invention belongs to the field of analog integrated circuits, and particularly relates to a low-power-consumption temperature sensor based on an MOS tube. A relaxation oscillator with a negative temperature characteristic is used as a temperature sensor, and the output square wave period and the temperature are in a linear relation. The MOS tube M1 in the oscillator has the dual functions of signal amplification and temperature sensing: on one hand, the common-gate amplifier is used for amplifying the voltage of an upper pole plate of a capacitor, increasing the input swing of a comparator and reducing the charge quantity of single charge and discharge, so that the power consumption is remarkably reduced; and on the other hand, the amplified signal improves the input slope at the overturning point of the comparator, the comparison speed is increased, and the influence of circuit noise on oscillator jitter is effectively suppressed. According to the invention, temperature sensing is carried out by using the voltage temperature characteristic of the MOS tube working in the sub-threshold region, the limitation of a traditional sub-threshold region current temperature sensing mode is avoided, low-power-consumption, high-resolution and high-precision measurement in a wide temperature range is realized, and the effective temperature sensing range of the MOS type temperature sensor is obviously widened.

To rapidly measure the magnitude of an external magnetic field.SOLUTION: A magnetoresistive relaxation oscillator magnetometer (1) includes: a capacitor (2); a charge resistor (3); a discharge resistor (4); a charge / discharge switch (5); a high voltage source terminal (6); a grounding terminal (7); and a signal output terminal (Vout). The charge resistor (3) comprises at least one charge magnetoresistive unit, and the discharge resistor (4) comprises at least one discharge magnetoresistive unit. The charge / discharge switch (5) is connected to the high voltage source terminal (6) and the high voltage source terminal (6) charges the capacitor (2) via the charge resistor (3) in a charge state, and the charge / discharge switch (5) is connected to the grounding terminal (7) and the capacitor (2) discharges electricity via the grounding terminal (7) by the discharge resistor (4) during a discharge stage.SELECTED DRAWING: Figure 1

The invention relates to oscillator circuits, corresponding systems and methods. A relaxation oscillator circuit includes one or more oscillator cores configured to generate an oscillating signal based on a controlled current applied thereto via a current flow line. The controlled current has a reduced standby value during a standby state of the oscillator circuit. The start-up circuit block is activated during a start-up phase of the oscillator circuit in response to a start-up enable signal asserted using a controlled current having a reduced standby value. The start-up circuit block includes a start-up current generator configured to generate a start-up current and to apply the start-up current from the start-up current generator to the oscillator core or one of the oscillator cores during a start-up phase.

The invention discloses an on-chip relaxation oscillator, a frequency stabilization method and a vehicle gauge level LED driving system, and relates to a semiconductor. At least two oscillation generation modules alternately work to generate periodic oscillation waveform data; collecting the voltage of the oscillation waveform data through a voltage average feedback active filter module and generating a direct current average voltage; comparing the DC average voltage with a reference voltage Vref and generating a feedback signal; the charging and discharging rate of the oscillation generation module is adjusted according to a feedback signal, the direct-current average voltage is stabilized at the reference voltage Vref by dynamically adjusting the overturning voltage threshold value of a comparator, and closed-loop stable control over the oscillation frequency is achieved; and the frequency stability and the electromagnetic compatibility are improved.

The present application belongs to the field of integrated circuit and switching power supply, and particularly relates to an RT current generating circuit with a clamping. RT On this basis, a current proportional to the current I is used to charge a capacitor, and a fixed current is used for comparison, and the voltage at the capacitor is fed back to the gate of an output current mirror, so that the upper and lower limits of the RT current capacitor are set, the size of the RT current is effectively limited, and it is ensured that the oscillator can work in a normal range even in the case that the RT resistance value is extremely high.