摘要:
A sampling rate converting method and apparatus for converting the sampling frequency of a 1-bit digital data obtained by a .SIGMA..DELTA. modulator to 32 kHz, 48 kHz, 96 kHz or 192 kHz without producing jitter. A decimation filter 3 decimates the sampling frequency of 1-bit digital data of 2.8224 MHz supplied from an input terminal 2 by 1/21-tuple decimation. An interpolation filter 4 oversamples the frequency of the output of the decimation filter 3 by quintuple oversampling with an integer ratio of 1:5. A decimation filter 5 decimates the frequency of the output of the interpolation filter 4 by 1/21-tuple decimation with an integer ratio of 21:1.
摘要:
Information is transmitted by a digital audio transmission line, which may include recording and play back from a digital audio disc, that includes information other than conventional two channel audio signals and error correction of the data transmitted in either direction between a user and a medium is provided. Information integrity is maintained by a first and second cross-interleave Reed-Solomon code (CIRC), in which a third Reed-Solomon code is overlaid on the CIRC code, whereby a sector is built from users words and protected by a quasi-product code, and then an encoded sector is divided into groups, which are group-wise presented to the CIRC encoder.
摘要:
The cash handling machine with a cash containing device housed within a safe and a receipt printer mounted on the safe comprises a cash carrying device for carrying cash from the cash containing device to an operation panel cash outlet and a receipt carrying device for carrying a printed receipt to an operation panel receipt outlet. Since the receipt carrying device is pivotally supported by the receipt printer at one end thereof and disposed obliquely between the receipt printer and the receipt outlet, it is possible to bring the receipt outlet into close proximity to the cash outlet in the operation panel even where the safe wall is sufficiently thick for crime prevention. Therefore, the user can readily take both the discharged cash and receipt simultaneously. Further, the receipt carrying device can be moved backward for easy access thereto in case of receipt jamming trouble.
摘要:
A pulse width modulated signal amplifier includes an integrator having a positive or non-inverted input terminal supplied with a modulating signal, such as, an audio signal, and an inverted input terminal supplied with a rectangular wave signal as a carrier, a high gain amplifier receiving the output of the integrator and producing a pulse width modulated signal, a pulse power amplifier receiving the pulse width modulated signal, a low pass filter receiving the output of the pulse power amplifier and producing an amplified demodulated signal corresponding to the original modulating signal and which is supplied to an output terminal, and a negative feedback circuit connected between the output terminal of the pulse power amplifier and the inverted input terminal of the integrator.
摘要:
A switching regulator includes a chopper circuit and a DC-DC converter. A switching signal for use with the chopper circuit is derived from an inverter portion of the DC-DC converter so as not to use an external pulse oscillator. A DC voltage feeback circuit is provided from the output of the DC-DC converter to the chopper circuit so as to stabilize the DC output signal of the DC-DC converter.
摘要:
A pulse amplifier formed of first and second field effect transistors, each exhibiting an inherent input capacitance at its gate electrode, the field effect transistors being connected in push-pull relation whereby their drain or source electrodes are connected to a common output terminal. First and second resistive circuits are connected in a pulse supply circuit to supply pulse signals to the respective gate electrodes of the field effect transistors. Each of the resistive circuits exhibits a higher resistance when a pulse is supplied therethrough to turn the respective field effect transistor ON and a lower resistance when the pulse is terminated to turn the respective field effect transistor OFF. The higher resistance of the resistive circuit cooperates with the inherent input capacitance of the respective field effect transistor to provide a higher discharge time constant to turn that field effect transistor ON and the lower resistance cooperates with the inherent input capacitance of the field effect transistor to provide a lower charge time constant to turn that field effect transistor OFF, whereby the field effect transistors are not ON concurrently. In a preferred embodiment, the field effect transistors are complementary field effect transistors so that a positive-going pulse turns one of those field effect transistors OFF while turning the other ON, and a negative-going pulse turns the one field effect transistor ON while turning the other OFF.
摘要:
A surge current protection circuit includes an input terminal supplied with a rectified alternating voltage, an output terminal to be connected to a load, and a semiconductor controlled rectifier having its anode and cathode electrodes connected in series between the input and output terminals. The collector and emitter electrodes of a control transistor are connected between the gate and cathode electrodes of the rectifier. The base-emitter voltage is supplied with any sharp transients, and the transistor becomes conductive before the rectifier if the transients are sharp enough and of high enough amplitude. Conduction of the transistor prevents the semiconductor controlled rectifier from conducting surge currents and protects circuits connected in series with the rectifier.
摘要:
A starting circuit for an inverter includes, at least, a control winding provided in connection with a saturable magnetic core of an input transformer of the inverter, a transistor and a capacitor. When a DC voltage source is activated, a discharge current of the capacitor flows through the collector-emitter circuit of the transistor and the control winding so as to start the switching operation of the inverter. A control circuit is provided for detecting a secondary voltage of the inverter so as to cut off the operation of the starting circuit after the inverter starts.
摘要:
A transistor inverter includes a pair of switching transistors each having base, emitter and collector electrodes, each of the collector and emitter circuits of which is connected between a DC voltage source through a primary winding of an output transformer, respectively, the secondary winding of which is connected to a rectifying circuit so as to produce a DC output voltage at its output. The transistor inverter also includes an input transformer with a saturable core and voltage feedback and current feedback circuits. The current feedback circuit has another transformer which controls the amount of current feedback, and the winding ratio of the primary and secondary windings is determined in connection with the current amplification factor of said first and second switching transistors in order to improve a switching speed of the switching transistors.