73results about How to "Reduce the oscillation frequency" patented technology

A switching power source comprises a current comparator 27 for comparing a voltage level of signals acquired by a current detector 9 with a reference voltage level VDT to produce detection signals VCP of first or second level L or H; an edge detector 28a for sensing an edge of drive signal VG supplied to a gate terminal of MOS-FET 3 during the period of transition from turning on to off of MOS-FET 3; and a decision means 28b for receiving a current detection signal VCP from current comparator 27 to produce an output signal VLD when edge detector 28a catches an edge of drive signal VG; wherein decision means 28b produces different output signals VLD of respectively first and second voltage levels L and H under the light and heavy load conditions to precisely and certainly detect on the primary side of transformer 2 the load condition on the secondary side of transformer 2 for improvement in conversion efficiency.

An object of this invention is to provide a phase synchronizing circuit capable of automatically adjusting a VCO such that the VCO satisfies a predetermined frequency range even in a frequency range in which the VCO oscillates by a leak current generated if a low threshold process is applied. The phase synchronizing circuit is composed of a PLL consisting of a phase comparator, a charge pump, a loop filter, a VCO, and a divider, and a calibration circuit for automatically adjusting a frequency range of the VCO. Before a convergence operation is started, a switch is closed in response to a signal Rst of the calibration circuit such that an output of the loop filter is leveled to the ground and the PLL is set to be an open loop. A VCO output Fo is set at an upper limit frequency or a lower limit frequency in response to a Vcal signal, and its frequency is measured by comparing its period with a period of a reference signal Fr, and signals Hb, Lb used for adjusting the frequency of the VCO are updated. The signals Hb, Lb are updated until the VCO satisfies the predetermined frequency range, and subsequently their values are maintained. The switch opens in response to the signal Rst, and the PLL is changed over to a close loop to start phase synchronization.

A thermoacoustic generator includes a housing with a thermoacoustic core supported in the housing. The core is operable to introduce acoustical power into the housing to thereby oscillate the pressure of the gas in the housing at a frequency. A piezoelectric alternator is also supported in the housing and has a face that is movable when acted on by the acoustical power. The alternator includes a portion of piezoelectric material operable to produce electrical power when acted upon by a stress. The piezoelectric material is in mechanical communication with the movable face so that movement of the face stresses the piezoelectric material. The alternator has a moving mass that serves as a substantial portion of the resonating mass inside the housing, thereby providing a pressure oscillation frequency in the housing substantially lower than for a similar system with a rigid member replacing the alternator.

A switching power source comprises a current comparator 27 for comparing a voltage level of signals acquired by a current detector 9 with a reference voltage level VDT to produce detection signals VCP of first or second level L or H; an edge detector 28a for sensing an edge of drive singal VG supplied to a gate terminal of MOS-FET 3 during the period of transition from turning on to off of MOS-FET 3; and a decision means 28b for receiving a current detection signal VCP from current comparator 27 to produce an output signal VLD when edge detector 28a catches an edge of drive signal VG; wherein decision means 28b produces different output signals VLD of respectively first and second voltage levels L and H under the light and heavy load conditions to precisely and certainly detect on the primary side of transformer 2 the load condition on the secondary side of transformer 2 for improvement in conversion efficiency.

To provide a highly stable crystal oscillator having increased thermal efficiency. The highly stable crystal oscillator comprises; a thermostat mainframe which maintains the temperature of a crystal resonator including a resonator container for sealing a crystal piece constant, an oscillating element which constitutes an oscillation circuit together with said crystal resonator, a temperature control element which controls the temperature inside of said thermostat mainframe, and a circuit board mounted with said thermostat mainframe, said oscillating element, and said temperature control element. The construction is such that a heat generating chip resistor and a highly heat sensitive element having a higher temperature dependency, among said oscillating element and said temperature control element, are arranged on one principal plane of said circuit board, and said heat generating chip resistor, said highly heat sensitive element, and said thermostat mainframe are directly heat bonded by a thermo-conductive material.

A power supply has a plurality of switching regulators providing a like plurality of regulated output voltages. The oscillators of the switching regulators are synchronized with one another by a synchronization signal. A synchronization signal detector is provided on one or more of the switching regulators to shift the switching frequency of the oscillator to a lower frequency upon detection of a synchronization signal.

A crystal oscillator is configured by accommodating a crystal blank that functions as a crystal unit and an IC chip that includes at least an oscillator circuit using the crystal blank into a container in an integrated manner. In the IC chip, the oscillator circuit is connected to the crystal unit via a pair of crystal connecting terminals, an output from the oscillator circuit is supplied to a plurality of output buffers. In relation to the crystal connecting terminal having a phase opposite to that of an output from the on / off controllable output buffer, an output terminal of this output buffer is disposed farther than an output terminal of the output buffer that is not subjected to the on / off control.

A digitally controlled oscillator includes a ring oscillator and a first supplementary circuit. The ring oscillator is coupled to a supply voltage and generates a signal oscillated at an oscillating frequency. The oscillating frequency is controlled by a digital code and further varies with a supply voltage drift in a first direction. The first supplementary circuit is coupled to the ring oscillator and facilitates the oscillating frequency to vary with the supply voltage drift in a second direction reverse to the first direction.

An oil pressure warning sensor for a pressure sensitive capacitor relates to a sensor, which comprises a telescoping oil tank main element, an oil tank telescoping component arranged in the telescoping oil tank main element, and a casing cooperating with the telescoping oil tank main element to close the oil tank telescoping component in the telescoping oil tank main element, wherein the telescoping oil tank main element comprises an iron-bottomed bowl and screws in sealed fit with through holes reserved at the bottom of the iron-bottomed bowl; the oil tank telescoping component comprises a sealing washer, a waveform return spring plate, a knurled spring plate, a sliding sleeve, a movable electrode plate, a return spring, a double-sided circuit board and a circuit board retaining snap ring, which are arranged in the iron-bottomed bowl in turn; a fixed electrode plate is arranged on one side, close to the movable electrode plate, of the double-sided circuit board; the movable electrodeplate and the fixed electrode plate form a capacitor with variable capacitance; upon receiving the pressure from the engine oil, the waveform return spring leaf and the knurled spring leaf deform anddrive the movable electrode plate to compress and deform the return spring so as to change the distance between the movable electrode plate and the fixed electrode plate to change the capacitance of the capacitor; and the oil pressure warning sensor for the pressure sensitive capacitor is further provided with a control circuit connected with the capacitor and used for converting the variation ofoil pressure into an electrical signal and transmitting the electric signal to an oil instrument.

An apparatus for determining and / or monitoring at least one physical or chemical, process variable of a medium and includes at least one mechanically oscillatable unit and at least one driving / receiving unit. The mechanically oscillatable unit includes a tube and an internal oscillator. The tube is connected to a securement unit with an end turned away from the process and the end of the tube turned toward the process is embodied as a free end. The tube surrounds the internal oscillator and the internal oscillator is secured to the end of the tube turned toward the process with an end turned toward the process. The driving / receiving unit excites the mechanically oscillatable unit to oscillate, respectively it receives the oscillations of the mechanically oscillatable unit. The internal oscillator has at least one groove / neck, which determines at least the oscillation frequency of the mechanically oscillatable unit.

A crystal oscillator is configured by accommodating a crystal blank that functions as a crystal unit and an IC chip that includes at least an oscillator circuit using the crystal blank into a container in an integrated manner. In the IC chip, the oscillator circuit is connected to the crystal unit via a pair of crystal connecting terminals, an output from the oscillator circuit is supplied to a plurality of output buffers. In relation to the crystal connecting terminal having a phase opposite to that of an output from the on / off controllable output buffer, an output terminal of this output buffer is disposed farther than an output terminal of the output buffer that is not subjected to the on / off control.

The invention provides a human body medium capacity transducer used in bed. The invention comprises two sheets of copper electrodes which tiles on a bed and are connected with a control circuit by a conducting line. The control circuit comprises an LC oscillator, a frequency-voltage transformer, a voltage comparator and a relay; wherein, the copper electrodes are connected with the LC oscillator, and the outputting of the oscillator is connected into the frequency-voltage transformer, the outputting of which is connected with the voltage comparator, the outputting of which controls the relay. The invention is convenient to use and install, and the exterior is an ordinary blanket which can be used when tiled on the bed. The capacitance variation of the transducer is obvious, thereby being very sensitive and reliable. The invention is just two copper sheets; therefore, the material is simple and the cost is low. The capacity of the transducer changes according the changing of the contacting area and medium without needing power source. The invention is easier than the traditional pressure switch type transducer in installation, more effective than human body pyroelectric sensor and more reliable than an opto-electrical reflect-typed or shot-typed transducer.

A power supply has a plurality of switching regulators providing a like plurality of regulated output voltages. The oscillators of the switching regulators are synchronized with one another by a synchronization signal. A synchronization signal detector is provided on one or more of the switching regulators to shift the switching frequency of the oscillator to a lower frequency upon detection of a synchronization signal.

An environment measuring device 1 has a measuring QCM sensor 10, a reference QCM sensor 20, a measurement oscillation circuit 15, a reference oscillation circuit 25, a frequency counter 31, s humidity sensor 51, a control unit 40, and a storage unit 41. The measuring QCM sensor 10 has an oscillator and an electrode formed by a corrosive metal on the surface of the oscillator, and the reference QCM sensor 20 has an oscillator and an electrode formed by a corrosion-resistant metal on the surface of the oscillator. The storage unit 41 stores the measurement count signal, the reference count signal, and the humidity signal which are associated with a measurement time. The control unit 40 determines an amount of increase in mass due to the corrosion of the electrode of the measuring QCM sensor by using the measurement count signal and the reference count signal.

The invention provides an over-voltage protection method achieved by the adoption of a dry-type air-core shunt reactor combined over-voltage protection circuit and belongs to the field of reactor over-voltage protection. The problems that an existing dry-type air-core shunt reactor combined over-voltage protection device recrudesces and is poor in over-voltage protection effect are solved. The cut-off current over-voltage protection is performed as follows, when a switch K of a circuit breaker is cut-off, cut-off current over-voltage occurs, i0 is set as a power frequency cut-off current value, U0 is set as a reactor power frequency voltage peak value, when t=0, the circuit breaker generates cut-off current, a resistance-capacitance protection device works, when the voltage on a protection device absorption capacitor C is not larger than the residual voltage of a lightning arrester, the resistance-capacitance protection device directly completes the cut-off current over-voltage protection on the reactor, when t=t0, the voltage on the protection device absorption capacitor C is larger than the residual voltage U1 of the lightning arrester, the lightning arrester makes action, when t=t1, the voltage on the protection device absorption capacitor C is less than or equal to the residual voltage U1 of the lightning arrester, the lightning arrester exits action, and the resistance-capacitance protection device continues to complete the cut-off current over-voltage protection on the reactor. The over-voltage protection method achieved by the adoption of the dry-type air-core shunt reactor combined over-voltage protection circuit is mainly used for reactors.

An inductor element 30 effectively functions even when formed on a substrate and comprises two upper and lower conductors 1, 2 spirally formed on the front side of a semiconductor substrate 3. The conductors 1, 2 have substantially the same shape. When viewed from the above of the front side of the substrate 3, the two conductors 1, 2 are superposed one on the other almost exactly. Lead wires 6a, 6b are connected to the outer end (outer peripheral end) and the inner end (center end) of the conductor 1, respectively. The outer end of the conductor 1 is connected to the inner end of the conductor 2 through a connection wire 6c. The conductor 1 functions as an inductor conductor and is connected to a circuit provided on the semiconductor substrate 3 through the lead wires 6a, 6b.

To provide an end point detection method applying a resonance phenomenon, an end point detection apparatus, and a chemical mechanical polishing apparatus on which the detection apparatus is loaded for monitoring variation in the thickness of an electrically conductive film in real time, reliably detecting a polishing end point of the electrically conductive film at high accuracy, without generating noise, low power consumption, and capable of reducing the cost.In order to achieve above described objects, the present invention provides an end point detection method applying a resonance phenomenon in which a polishing end point is detected when the electrically conductive film is polished and removed to an appropriate thickness, wherein a sensor 37 composed of an oscillation circuit of the Colpitts type or the like having a planar inductor and a concentrated constant capacitor is used, and the variation in the thickness of the electrically conductive film is monitored in real time from the variation in the oscillation frequency of the sensor 37 caused along with the variation in the thickness of the electrically conductive film opposed to the planar inductor.

The power supply apparatus includes an inductor; a switching element, which is connected in series to the inductor, and is configured to be driven in accordance with an input pulse signal; and a booster circuit, which is connected to both ends of the inductor, and includes a plurality of rectification units each including a diode and a capacitor, wherein the power supply apparatus is configured to repeat an operation of successively driving the switching element in accordance with the input pulse signal in a cycle that is longer than a cycle in which the switching element is successively driven.

A digitally controlled oscillator includes a ring oscillator and a first supplementary circuit. The ring oscillator is coupled to a supply voltage and generates a signal oscillated at an oscillating frequency. The oscillating frequency is controlled by a digital code and further varies with a supply voltage drift in a first direction. The first supplementary circuit is coupled to the ring oscillator and facilitates the oscillating frequency to vary with the supply voltage drift in a second direction reverse to the first direction.

A class D amplifier includes an output stage that performs a switching operation, a feedback circuit that generates a feedback signal based on the output signal output from the output stage, an integration amplifier that outputs an integrated value signal in response to an input signal and the feedback signal, a comparator that compares the integrated value signal with a standard signal, a driver that controls the output stage based on a signal output from the comparator, a carrier signal generator that generates a carrier signal, a reference signal generator that outputs a reference signal indicating a driving amount for a load at the output stage, and a standard signal switch that switches the standard signal to the carrier signal or a standard potential based on whether a level of the reference signal is smaller than a threshold value.

The present invention discloses a power supply (24) having a plurality of switching regulators (150, 152, 154) providing a like plurality of regulated output voltages (1.2V, 1.8V, 3.3V). The oscillators (28) of the switching regulators are synchronized with one another by a synchronization signal (SYNC, INPUT). A synchronization signal detector (62) is provided on one or more of the switching regulators to shift the switching frequency of the oscillator to a lower frequency upon detection of a synchronization signal.

A method of tuning a filter to a desired frequency using a stepwise approximation. The elements of the filter are selected according to the control code used to change the oscillation frequency of the filter. The control code is set to the middle of the control code range, and the resulting oscillation frequency is compared to the desired frequency. If the control code needs to be increased, the control code is set to 3 / 4 of the control code range. If the control code needs to be reduced, the control code is set to 1 / 4 of the control code range. This method successively uses a stepwise approximation to determine the value of each bit of the control code. Thus, a stepwise approximation is used to converge on the value of the control code that produces the filter's oscillation frequency closest to the desired frequency (with a maximum error of 1 least significant bit).

Provided are an oscillation circuit, a booster circuit, and a semiconductor device capable of reducing power consumption when a power supply voltage is high. In a ring oscillator circuit which is the oscillation circuit, a PMOS transistor in each of inverter circuits has a substrate connected to a first power supply voltage, and a source connected to a drain of a PMOS transistor, which is a first constant current element configured to control a supply current to the inverter circuit, and the PMOS transistor, which is the first constant current element, has a source connected to a second power supply voltage VREG, which serves as a constant voltage when the first power supply voltage is at a predetermined voltage or higher.

A receiver using a harmonic mixer includes a signal receiver for receiving a first signal, a frequency generator for synchronizing a phase of the received first signal, down-converting a frequency size of the synchronized first signal as much as a first size, and outputting the down-converted signal as a second signal; a first harmonic mixer unit for receiving the first signal and the second signal, generating a third signal having a frequency size down-converted as much as a second size, and outputting the third signal. The receiver further includes a second harmonic mixer unit for receiving the third signal and outputting an In-phase signal having a frequency size down-converted as much as a third size, and a third harmonic mixer unit for receiving the third signal and outputting a Quadrature-phase signal having a frequency size down-converted as much as a third size.

A circuit device includes a drive circuit driving a resonator, an oscillation circuit having the resonator and a variable capacitance circuit coupled to an oscillation loop including the drive circuit, and a D / A converter circuit that performs D / A conversion on frequency control data and outputs a first voltage signal and a second voltage signal which are differential signals. The variable capacitance circuit includes a first variable capacitance capacitor, to one end of which the first voltage signal is input and, to the other end of which a first bias voltage is input and a second variable capacitance capacitor, to one end of which the second voltage signal is input and, to the other end of which a second bias voltage is input.

The invention relates to an FPGA service life test method, and belongs to the technical field of FPGA chip service life test. The method comprises the following steps: 1) setting various configurations of a life test circuit; 2) setting external excitation conditions required by the test; and (3) measuring the junction temperature of the device by using an interpolation ring oscillation circuit so as to realize feedback modification and iterative optimization on the working frequency of an input clock, and monitoring the state of the device in the life test process through an LED state indicator lamp connected with the FPGA so as to ensure that the junction temperature reaches a specified value in the life test process. According to the life test method, temperature test is carried out through a method of interpolating a ring oscillation circuit. After the linear relation between the oscillation frequency and the temperature is established, the corresponding temperature can be obtained only through the output frequency of the ring oscillator.

A frequency calibration loop circuit having a pre-set frequency channel word (FCW) command value, a bit inputted to obtain a target frequency in an oscillator and a pre-set minimum division ratio n (n is a constant) of a programmable divider, includes: an oscillator adjusting an oscillation frequency of an oscillation signal according to a control value; a programmable divider dividing the oscillation signal according to a division ratio to output a divided signal; a counter counting the number of clocks of the divided signal for one cycle of a reference signal to output a count value; and a frequency detector obtaining the control value by subtracting the count value from a reference comparison value, wherein the reference comparison value is obtained by dividing a Frequency Channel Word (FCW) command value by a minimum division ratio of the programmable divider.