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:
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:
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:
An object of this invention is to provide a D/A converter of a multibit type for improving its performance by reducing dispersion of the electric currents of plural electric current sources as much as possible. To achieve this object, the D/A converter has a constant electric current source (10) constructed by 2N (N=2, 3, - - - and here, N=16) constant electric current sources having constant electric current values equal to each other; selecting means (7, 8) for selecting Di constant electric current sources according to input data Di {here, Di=0, 1, 2, 3, - - - (2N−1)} having N-bits in input word length so as to use these 2N constant electric current sources one by one until a sum of values of one input data or continuous plural input data among these 2N constant electric current sources exceeds 2N; and electric current adding means (9) for adding each of the constant electric currents from the Di constant electric current sources selected by the selecting means to each other.
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:
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; and a control section operable to perform a muting process by causing the gain-adjusting section to set the gain of the digital audio signal to a zero level, the dither-superposing section to stop superposing the dither, and the pulse-width changing section to change, step by step, the ratio between the “high” state and the “low” state of the pulse-width modulated signal toward the “low” state upon receipt of a predetermined muting signal for muting the digital audio signal, thereby maintaining the “low” state and stopping the switching operation performed in accordance with the pulse-width modulated signal.
摘要:
A power amplifier apparatus includes a dither superimposing unit superimposing DC dither on a digital signal; a switching signal generating unit converting the digital signal on which the DC dither is superimposed by the dither superimposing unit to a pair of drive pulses on high and low sides having opposite levels; and a cancel signal generating unit generating a cancel signal to cancel a DC component caused by the DC dither by changing a ratio of pulse widths of the drive pulses on the high and low sides generated by the switching signal generating unit.
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:
This invention is an improved process for the conversion of a C.sub.9 mixed alkyl aromatic feedstream containing ethyl substituted aromatics to a product rich in toluenes and/or xylenes via catalytic transalkylation/disproportionation using a palladium loaded moderately, dealuminated mordenite catalyst in the presence of added hydrogen and benzene.