摘要:
A low insertion-withdrawal force electric connector is disclosed wherein a pin is mounted on one side wall of a male housing; a groove into and out of which said pin is movable is provided in a hood of a female housing; a cam lever is pivotally mounted on said hood; and the cam lever has at its front end an eccentric cam groove which is engageable with the pin so as to cause said two housings to be fitted and disengaged relative to each other in response to the pivotal movement of said lever. A fitting-side acting surface of the eccentric cam groove against the pin is disposed generally perpendicular to the direction of advance of said pin when the two housings are completely fitted together.
摘要:
In a terminal protection type connector in which a flexible locking arm for locking a female connector housing is provided on a male connector housing, and the elastic contacts of terminals accommodated in the male connector housing are exposed through openings formed in the latter, a terminal protecting member is slidably mounted on the male connector housing in such a manner that said terminal protecting member covers the openings and engages with the flexible locking arm.
摘要:
In locking metal terminals in a connector, a terminal locking jig having engaging prongs which are extended respectively so as to be engaged with terminal accommodating chambers in the rear end portion of a connector housing is inserted into a terminal-locking-member accommodating chamber formed surrounding the terminal accommodating chambers, to drive the metal terminals which are not completely locked yet to the positions where the metal terminals are completely locked, and thereafter a terminal locking element having engaging prongs which are extended in the same manner is inserted into the connector housing from the rear or side. Thus, the terminal locking member can be engaged with the connector housing with ease.
摘要:
A signal amplification apparatus which supplies an input signal to a signal processing section to perform signal processing on the input signal, amplifies a power supply voltage supplied from a power source section in accordance with the processed signal, and outputs the amplified power supply voltage. The apparatus includes output decrease prediction means for predicting decrease of the output signal on the basis of an amplitude of the input signal; power supply voltage correction signal generation means for generating a power supply voltage correction signal for correcting the power supply voltage of the power source section on the basis of the predicted decrease of the output signal; and feedforward control means for performing feedforward control of the power supply voltage of the power source section by using the power supply voltage correction signal.
摘要:
In an audio amplifier having a D-class power amplifier, a noise upon muting is suppressed. A sampling rate converter circuit for sampling rate converting a digital audio signal into a digital audio signal, and a ΔΣ modulation circuit for re-quantizing the digital audio signal into a bit-reduced digital audio signal are provided. Further, a PWM modulation circuit for converting the digital audio signal into a PWM signal, and a D-class power amplifier to which the PWM signal are supplied. Still further, a dither signal forming circuit for superimposing a dither signal SDI on the digital audio signal, and a forming circuit for forming a muting signal SDET are provided. Upon muting, an input side of the sampling rate converter circuit is stopped by the muting signal SDET.
摘要:
A digital power amplifier includes a pulse width modulator for converting an input signal into a pulse width modulated signal according to a signal level of the input signal; an output stage, switching thereof being controlled by the pulse width modulated signal generated by the pulse width modulator; a pulse width modulation ratio detector for detecting a pulse width modulation ratio of the pulse width modulated signal generated by the pulse width modulator; and a control unit for disabling the switching operation of the output stage. The control unit disables the switching operation of the output stage when the pulse width modulation ratio detector detects that the pulse width modulation ratio is 50%.
摘要:
A digital amplifier apparatus includes a gain-adjusting section operable to adjust a gain of a digital audio signal; a dither-superposing section operable to superpose a predetermined dither on the digital audio signal; a pulse-width-modulated signal generating section operable to generate a pulse-width-modulated signal corresponding to the digital audio signal; an amplifying section operable to cause a switching element to perform a switching operation in accordance with the pulse-width-modulated signal; a pulse-width changing section operable to change a ratio between a “high” state and a “low” state of the pulse-width modulated signal; a synchronizing section operable to synchronize the pulse-width modulated signal with a reset signal that resets the digital audio signal; and a control section operable to perform a resetting operation by setting the gain of the digital audio signal to a zero level upon receiving the reset signal, stopping the superposing of the dither to thereby generate the pulse-width modulated signal, and setting the pulse-width modulated signal to the “low” state by using the pulse-width modulated signal synchronized with the reset signal, thereby causing the switching element to stop performing the switching operation.
摘要:
A sound field correction apparatus that corrects a sound field characteristic by supplying a measurement signal used for measurement purposes to drive a plurality of speakers arranged at arbitrary positions to reproduce the measurement signal and receiving a collected sound signal obtained by collecting the sound reproduced from the plurality of speakers with a sound collector disposed at an arbitrary listening point is disclosed. The sound field correction apparatus includes: a measurement signal supplier, a receiver, a delay calculator, a sound pressure level difference calculator, a delay correction value calculator, and a gain correction value calculator.
摘要:
A power amplifier for reducing emission generated at the edges of output voltages. A pair of PWM modulation circuits (11) and (12) to which an input signal is sent; a pair of push-pull circuits (15) and (16); and drive circuits (13) and (14) for sending the outputs of the PWM modulation circuits (11) and (12) as drive signals to the push-pull circuits (15) and (16) are provided. A speaker (19) is connected between the output end of the push-pull circuit (15) and the output end of the push-pull circuit (16). The drive circuits (13) and (14) are switched at intervals equal to the cycle period of pulse modulation signals such that the drive signals sent to the push-pull circuits (15) and (16) are not changed at the end points of each cycle period of the pulse modulation signals.
摘要:
A power amplifier circuit includes a pair of PWM circuits, to which an input signal is supplied, a pair of push-pull circuits, and drive circuits for supplying the outputs of the PWM circuits to the push-pull circuits as drive signals. A speaker is arranged between the output end of one push-pull circuit and the output end of the other push-pull circuit. The drive circuits alternately drive the respective push-pull circuits every cycle time of a PWM signal. The circuit can suppress radiation caused by the variation in output voltages.