摘要:
A ring oscillator for circulating pulse edges of two types therein includes an even number of inverting circuits connected in a ring. Each of the inverting circuits is operative to invert an input signal and output an inversion of the input signal. One of the inverting circuits is a first start inverting circuit which starts an operation of inverting an input signal in response to a first control signal applied from an external input. One of the inverting circuits except the first start inverting circuit and an inverting circuit immediately following the first start inverting circuit is a second start inverting circuit which starts an operation of inverting an input signal in response to a second control signal. A control signal inputting arrangement serves to input the second control signal to the second start inverting circuit during an interval from a first moment at which the first control signal is inputted into the first start inverting circuit and the first start inverting circuit starts the inverting operation to a second moment at which a pulse edge initially generated by the start of the inverting operation of the first start inverting circuit and travelling while being sequentially inverted by the inverting circuits enters the second start inverting circuit.
摘要:
A ring oscillator for circulating pulse edges of two types therein includes an even number of inverting circuits connected in a ring. Each of the inverting circuits is operative to invert an input signal and output an inversion of the input signal. One of the inverting circuits is a first start inverting circuit which starts an operation of inverting an input signal in response to a first control signal applied from an external input. One of the inverting circuits except the first start inverting circuit and an inverting circuit immediately following the first start inverting circuit is a second start inverting circuit which starts an operation of inverting an input signal in response to a second control signal. A control signal inputting arrangement serves to input the second control signal to the second start inverting circuit during an interval from a first moment at which the first control signal is input into the first start inverting circuit and the first start inverting circuit starts the inverting operation to a second moment at which a pulse edge initially generated by the start of the inverting operation of the first start inverting circuit and travelling while being sequentially inverted by the inverting circuits enters the second start inverting circuit.
摘要:
A method of placing delay units of a pulse delay circuit on a programmable logic device having logic cells in each of cell strings has a step of arranging each delay unit in one logic cell of the device such that the delay units are placed in respective specific cell strings aligned in a row direction and a step of serially connecting the delay units with one another as a straight delay line such that the delay units placed in the specific cell strings in the connecting order are aligned in the row direction. In the device, an inter-string transmission delay time on a line between two logic cells of different cell strings differs from an intra-string transmission delay time on a line between two logic cells of one cell string.
摘要:
An inverter circuit configuring a delay unit is a so-called CMOS transistor including a PMOS transistor and an NMOS transistor, of which respective gates are interconnected and respective drains are interconnected. The source and a back gate of the NMOS transistor are connected to the ground. The source of the PMOS transistor is connected to a positive drive terminal and controlled by an analog input signal. The back gate of the PMOS transistor is connected to a control terminal and controlled by a control signal.
摘要:
In a digital control pulse generator including a ring oscillator composed of multiple inversion circuits connected in a ring for circulating a pulse, a counter and selectors which turn data of a flip-flop to high when a counted value of the pulse from a terminal of the ring oscillator becomes a value corresponding to ten high order bits of control data, a pulse selector for taking out a clock of the flip-flop from the inversion circuit at the position specified by four bit control data and a delay line and logical product circuit which turn an output signal of the system to a high level for a predetermined time when the output of the flip-flop turns high, a register and adder accumulate the four low order bits of the control data every time the output signal turns high to update the data four bit data. As a result, the ring oscillator may be continuously operated and an oscillation cycle proportional to the control data may be set.
摘要:
In a device for encoding a pulse phase difference or controlling an oscillation frequency based on delayed signals sequentially output by a delay circuit, the encoding of a pulse phase difference or the oscillation control can be simultaneously performed using a single delay device. There is provided a frequency converter including a ring oscillator consisting of inverting circuits interconnected in the form of a ring, a pulse phase difference encoding circuit for encoding the cycle of a reference signal into a binary digital value based on a pulse output by the ring oscillator, an arithmetic circuit for multiplying or dividing the binary digital value by a predetermined value to generate control data and a digitally controlled oscillation circuit for generating a pulse signal in a cycle in accordance with the control data based on the pulse output by the ring oscillator, the ring oscillator being shared by the encoding circuit and oscillation circuit. This makes the time resolution of the encoding and oscillation circuits constant, thereby allowing accurate frequency conversion.
摘要:
A physical quantity detecting is capable of easily adjusting sensitivity and an offset of a detected output without being increased in size. In a signal processor for driving a sensor element in which fixed electrodes are disposed on both sides of a movable electrode displaced in response to acceleration, a signal generator generates PWM signals PA and PB in which an invalid control period during which the fixed electrodes are both deenergized only during a period corresponding to data M3 stored in a memory, is, at a predetermined ratio, inserted into a valid control period during which the fixed electrodes are alternately energized and their energization ratio is controlled so that the movable electrode is placed in position. Since the sensitivity of the sensor element to the acceleration changes according to the length of the invalid control period which does not contribute to control of the position of the movable electrode, its sensitivity can be easily adjusted by simply changing the value set in the memory.
摘要:
A programmable delay line comprises a plurality of delay stages connected in series, each of the delay stages including: a basic path for passing an input signal; a delay path for passing the input signal with a predetermined delay time; and a selector for selecting either the basic path or the delay path to pass the input signal in accordance with digital data externally inputted, wherein differences in times for passing the input signal through the basic path and through the delay path in the plurality delay stages are UD.2.sup.n (n=0, 1, 2 . . . ), UD being unit delay time. A programmable delay apparatus comprises: an oscillator and counter, which determine a coarse delay time in accordance with the upper bit data of control data, and a programmable delay line, which determines a fine delay time according to the lower bit data of the control data after the finish of the coarse delay time to obtain a total delay time. The counter provides a wide range of available delay times. The oscillator of the programmable delay apparatus can be controlled by a control signal. Addition of a feedback circuit for supplying the delay signal from the delay line as the control signal to the oscillator of the programmable delay apparatus provides a digital controlled oscillator.
摘要:
A frequency multiplying device which multiplies the frequency of an externally-supplied reference signal PREF includes a digitally-controlled oscillation circuit, which includes a ring oscillator formed of thirty-two inverting circuits in a ring configuration which are adapted to generate sixteen clock signals having a period that is thirty-two times the inversion time of each inverting circuit and a phase interval that is twice the inverting circuit inversion time, and produces an output signal POUT having a period that corresponds to frequency control data CD at a resolution of the phase difference time of the clock signals, a counter/data-latch circuit which counts the clock signal RCK released by the ring oscillator within one period of the reference signal PREF and delivers the frequency control data CD of the count value to the digital oscillation circuit, and a control circuit which controls the operation of the circuits so that the oscillation output signal POUT having the frequency of the reference signal PREF multiplied by sixteen (32/2) is generated by the digital oscillation circuit.
摘要:
A method of placing delay units of a pulse delay circuit on a programmable logic device having logic cells in each of cell strings has a step of arranging each delay unit in one logic cell of the device such that the delay units are placed in respective specific cell strings aligned in a row direction and a step of serially connecting the delay units with one another as a straight delay line such that the delay units placed in the specific cell strings in the connecting order are aligned in the row direction. In the device, an inter-string transmission delay time on a line between two logic cells of different cell strings differs from an intra-string transmission delay time on a line between two logic cells of one cell string.