Abstract: A single printed-circuit board of a class-D amplifier includes an input ground, an output ground, an input amplifying circuit, a modulation circuit, an output amplifying circuit, and an output filter, a solid pattern, a first feedback circuit, and a second feedback circuit. The solid pattern of the output ground extends into all regions of the input amplifying circuit, the modulation circuit, the output amplifying circuit and the output filter. The first feedback circuit executes a feedback where a voltage at a first connecting point is negatively fed back to an inverting input of the input amplifying circuit. The second feedback circuit executes a feedback where a voltage at a second connecting point is negatively fed back to a non-inverting input of the input amplifying circuit.

Abstract: In a switching power supply, a rectifying circuit outputs a first voltage. A switching circuit switches the first voltage into a switching voltage. An output circuit generates a second voltage based on the switching voltage. A feedback circuit generates the feedback signal based on the first and second voltages, and includes a carrier wave generation circuit that generates a carrier wave. The carrier wave has a non-linear shape at its rising edge and/or falling edge. A PWM circuit generates a PWM signal based on a comparison between the first voltage and a voltage of the carrier wave. Due to the non-linear shape, as the first voltage is higher, a pulse width of the PWM signal is changeable more greatly based on a change in the first voltage. A low-pass filter generates the feedback signal based on the PWM signal.

Abstract: A vibration controller includes: a piezoelectric element fixed to an object of control; and a quasi-inductor circuit and a negative resistance circuit connected in series to the piezoelectric element.

Abstract: 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.

Abstract: A vibration controller includes: a piezoelectric element fixed to an object of control; and a quasi-inductor circuit and a negative resistance circuit connected in series to the piezoelectric element.

Abstract: 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.

Abstract: The present invention provides a rainwater catchment apparatus that is easily installed without renovating a building. The rainwater catchment apparatus comprises a rainwater inlet for introducing rainwater, a flange portion engaged with a peripheral portion of a rainwater outlet serving as a leading end of a drainage canal formed in a building framework for introducing rainwater in the rainwater inlet, a drain portion for discharging excessive water exceeding a predetermined level to the drainage canal, a reservoir freely fitted into the drainage canal through the rainwater outlet, and a pumping mechanism for pumping water stored in the reservoir to the outside.

Abstract: The present invention provides a rainwater catchment apparatus that is easily installed without renovating a building. The rainwater catchment apparatus comprises a rainwater inlet for introducing rainwater, a flange portion engaged with a peripheral portion of a rainwater outlet serving as a leading end of a drainage canal formed in a building framework for introducing rainwater in the rainwater inlet, a drain portion for discharging excessive water exceeding a predetermined level to the drainage canal, a reservoir freely fitted into the drainage canal through the rainwater outlet, and a pumping mechanism for pumping water stored in the reservoir to the outside.