Abstract: A sound signal processing device supplies an output sound signal to an amplification device configured to supply a first sound signal to a high-frequency speaker and a low-frequency speaker. The sound signal processing device includes a high-pass filter, an amplitude limitation circuit, a low-pass filter, and a synthesis circuit. The high-pass filter removes a low-frequency component from an input sound signal to generate a high-frequency sound signal. The amplitude limitation circuit limits an amplitude of the input sound signal at or below a reference value to generate a second sound signal. The reference value corresponds to a clipping voltage of the amplification device. The low-pass filter removes a high-frequency component from the second sound signal to generate a low-frequency sound signal. The synthesis circuit synthesizes the high-frequency sound signal and the low-frequency sound signal to generate the output sound signal.

Abstract: A sound signal processing device supplies an output sound signal to an amplification device configured to supply a first sound signal to a high-frequency speaker and a low-frequency speaker. The sound signal processing device includes a high-pass filter, an amplitude limitation circuit, a low-pass filter, and a synthesis circuit. The high-pass filter removes a low-frequency component from an input sound signal to generate a high-frequency sound signal. The amplitude limitation circuit limits an amplitude of the input sound signal at or below a reference value to generate a second sound signal. The reference value corresponds to a clipping voltage of the amplification device. The low-pass filter removes a high-frequency component from the second sound signal to generate a low-frequency sound signal. The synthesis circuit synthesizes the high-frequency sound signal and the low-frequency sound signal to generate the output sound signal.

Abstract: A MEMS device including a fixed member and a movable member supported via a resilient body. The MEMS device includes an impact alleviation mechanism provided at a position where the movable member and the fixed member collide during operation. The impact alleviation mechanism includes a stopper provided to either the fixed member or the movable member and that protrude to be parallel between sides of the two members with at least one side edge fixed to the respective member. Moreover, the impact alleviation mechanism includes an elongate protruding member provided on the other of the fixed member and the movable member. The elongate protruding member and the stopper are configured such that as collision force increases between the movable member and the fixed member during operation, an abutment area of an outer edge position of the elongate protruding member approaches the fixed side edge of the stopper.

Abstract: A vibrator drive circuit is configured to drive a vibrator mass 3 in a prescribed vibration direction. The vibrator drive circuit includes a drive unit configured to drive a vibrator based on a reference signal SG1 of a predetermined frequency to cause the vibrator to vibrate in a vibration direction, a phase detector configured to detect a vibration waveform of the vibrator in the vibration direction and to output an output voltage Vcnt in accordance with a phase difference between reference signal SG1 and a vibration waveform thereof, and two capacitors each formed of a movable electrode provided in the vibrator and a fixed electrode provided to face the movable electrode, the output voltage Vcnt being applied to the fixed electrode. The phase detector is configured to adjust the output voltage Vcnt in accordance with the phase difference, thereby changing electrostatic force in each of the capacitors for controlling the phase difference to be 90 degrees.

Abstract: A MEMS structure includes a planar substrate, a support body coupled to the planar substrate, a fixed electrode coupled to the planar substrate and a moveable portion. The movable portion is spaced from and faces the fixed electrode. The movable electrode includes a movable weight and an intermediate frame surrounding an outer edge of the movable weight. A plurality of elastic supports connect the movable weight to the intermediate frame. The elastic supports are elastically deformable in a first direction extending parallel to the plane of the substrate such that the movable weight can move in the first direction. At least one torsion bar pivotally connects one end of the intermediate frame to the support body so as to allow the intermediate frame, and with it the movable weight, to pivot around an axis which extends parallel to the plane of the substrate and perpendicular to the first direction.

Abstract: A MEMS device including a fixed member and a movable member supported via a resilient body. The MEMS device includes an impact alleviation mechanism provided at a position where the movable member and the fixed member collide during operation. The impact alleviation mechanism includes a stopper provided to either the fixed member or the movable member and that protrude to be parallel between sides of the two members with at least one side edge fixed to the respective member. Moreover, the impact alleviation mechanism includes an elongate protruding member provided on the other of the fixed member and the movable member. The elongate protruding member and the stopper are configured such that as collision force increases between the movable member and the fixed member during operation, an abutment area of an outer edge position of the elongate protruding member approaches the fixed side edge of the stopper.

Abstract: A MEMS structure includes a planar substrate, a support body coupled to the planar substrate, a fixed electrode coupled to the planar substrate and a moveable portion. The movable portion is spaced from and faces the fixed electrode. The movable electrode includes a movable weight and an intermediate frame surrounding an outer edge of the movable weight. A plurality of elastic supports connect the movable weight to the intermediate frame. The elastic supports are elastically deformable in a first direction extending parallel to the plane of the substrate such that the movable weight can move in the first direction. At least one torsion bar pivotally connects one end of the intermediate frame to the support body so as to allow the intermediate frame, and with it the movable weight, to pivot around an axis which extends parallel to the plane of the substrate and perpendicular to the first direction.

Abstract: A vibrator drive circuit is configured to drive a vibrator mass 3 in a prescribed vibration direction. The vibrator drive circuit includes a drive unit configured to drive a vibrator based on a reference signal SG1 of a predetermined frequency to cause the vibrator to vibrate in a vibration direction, a phase detector configured to detect a vibration waveform of the vibrator in the vibration direction and to output an output voltage Vcnt in accordance with a phase difference between reference signal SG1 and a vibration waveform thereof, and two capacitors each formed of a movable electrode provided in the vibrator and a fixed electrode provided to face the movable electrode, the output voltage Vcnt being applied to the fixed electrode. The phase detector is configured to adjust the output voltage Vcnt in accordance with the phase difference, thereby changing electrostatic force in each of the capacitors for controlling the phase difference to be 90 degrees.

Abstract: A resonance frequency adjustment module is disclosed forming a MEMS sensor for detecting an angular velocity. The resonance frequency adjustment module includes a movable electrode; a fixed electrode facing the movable electrode to form a capacitor; and an elastic body supporting the movable electrode so as to be displaceable in one direction. The movable electrode and the fixed electrode have surfaces facing each other to form a capacitor, and the surface can be inclined to a displacement direction. A region sandwiched between the movable electrode and the fixed electrode has a volume fixed region where the volume is not decreased by movement of the movable electrode.

Abstract: A MEMS sensor module of the present invention, in particular, a vibration driving module includes: a movable electrode supported such that the movable electrode is able to be vibrated, the movable electrode extending in a vibration direction; a fixed electrode provided substantially in parallel with the movable electrode and extending in the vibration direction; a plurality of projection portions provided side by side on a facing wall surface of the movable electrode in the vibration direction, the facing wall surface of the movable electrode facing the fixed electrode; and a plurality of projection portions provided on a facing wall surface of the fixed electrode, the facing wall surface of the fixed electrode facing the movable electrode, the plurality of projection portions of the fixed electrode facing the projection portions of the movable electrode.

Abstract: A power amplifying circuit includes a first field effect transistor and a second field effect transistor that are connected in series, are interposed between a high potential power line and a low potential power line, and drive a load; a predriver that generates, in response to an input signal, gate voltages applied to the first field effect transistor and the second field effect transistor respectively; and a variable power source that supplies source voltages to the high potential power line and the low potential power line respectively, and is configured to control the source voltages.

Abstract: A voltage generation circuit includes a voltage detection circuit that generates a detection voltage according to an output voltage, a reference voltage generation circuit that generates a reference voltage which changes periodically, a comparison circuit that generates a control signal according to a result of a comparison between the detection voltage and the reference voltage, wherein control pulses each having a pulse width according to the detection voltage are sequentially appeared in the control signal, and a driving pulse generation circuit that generates a driving pulse corresponding to the control pulse and supplies the generated driving pulse to a transistor connected to a DC power source when the pulse width of the control pulse exceeds a predetermined width, and stops generating the driving pulse when the pulse width of the control pulse becomes smaller than the predetermined width.

Abstract: A voltage adder circuit includes an amplifier circuit having a first operational amplifier and into which a first voltage is input, a circuit that supplies an output current to the amplifier circuit, and a current providing section that detects the output current of the circuit and supplies an output current equal to the output current of the circuit in magnitude so that the output current of the circuit is prevented from inputting to or outputting from the first operational amplifier through an output terminal of the first operational amplifier. A second voltage is input into the circuit.

Abstract: A voltage generation circuit includes a voltage detection circuit that generates a detection voltage according to an output voltage, a reference voltage generation circuit that generates a reference voltage which changes periodically, a comparison circuit that generates a control signal according to a result of a comparison between the detection voltage and the reference voltage, wherein control pulses each having a pulse width according to the detection voltage are sequentially appeared in the control signal, and a driving pulse generation circuit that generates a driving pulse corresponding to the control pulse and supplies the generated driving pulse to a transistor connected to a DC power source when the pulse width of the control pulse exceeds a predetermined width, and stops generating the driving pulse when the pulse width of the control pulse becomes smaller than the predetermined width.

Abstract: A voltage generation circuit includes a voltage detection circuit that generates a detection voltage according to an output voltage, a reference voltage generation circuit that generates a reference voltage which changes periodically, a comparison circuit that generates a control signal according to a result of a comparison between the detection voltage and the reference voltage, wherein control pulses each having a pulse width according to the detection voltage are sequentially appeared in the control signal, and a driving pulse generation circuit that generates a driving pulse corresponding to the control pulse and supplies the generated driving pulse to a transistor connected to a DC power source when the pulse width of the control pulse exceeds a predetermined width, and stops generating the driving pulse when the pulse width of the control pulse becomes smaller than the predetermined width.

Abstract: A controller 100 updates data LVLm indicative of a level section of an input audio signal and controls a reference level Vr based on a signal CMP representative of a comparison result between the input audio signal and the reference level Vr, and further, controls gains of electronic volumes 10L and 10R in such a manner that these gains become such gains corresponding to the level section of the input audio signal. In this case, the level sections of the input audio signals are related to the gains in such a manner that levels of output signals of the electronic volumes do not exceed a previously set output amplitude upper limit level.

Abstract: A pulse monitor circuit detects the presence or non-presence of the output pulses output from an output stage circuit. The pulse monitor circuit outputs an up signal to the up/down counter when the output pulses do not exist at all and outputs a down signal to the up/down counter when the output pulses exist. The up/down counter outputs a signal for increasing the delay amount of a delay amount variable circuit when a count value is large, that is, when the output pulses disappear. In contrast, when the count value is small, that is, when the output pulses exist, the counter outputs the signal for reducing the delay amount of the delay amount variable circuit.

Abstract: An N-channel transistor is provided as a switch between a high potential power line and a low potential power line. A high-pass filter is constituted by a capacitor and a resistor. When a voltage between the high potential power line and the low potential power line is started to oscillate by a switching operation, the high-pass filter causes a high-pass component thereof to pass, thereby turning ON the N-channel transistor to reduce a ringing.

Abstract: A power amplifying circuit includes a first field effect transistor and a second field effect transistor that are connected in series, are interposed between a high potential power line and a low potential power line, and drive a load; a predriver that generates, in response to an input signal, gate voltages applied to the first field effect transistor and the second field effect transistor respectively; and a variable power source that supplies source voltages to the high potential power line and the low potential power line respectively, and is configured to control the source voltages.

Abstract: A voltage adder circuit includes an amplifier circuit having a first operational amplifier and into which a first voltage is input, a circuit that supplies an output current to the amplifier circuit, and a current providing section that detects the output current of the circuit and supplies an output current equal to the output current of the circuit in magnitude so that the output current of the circuit is prevented from inputting to or outputting from the first operational amplifier through an output terminal of the first operational amplifier. A second voltage is input into the circuit.