Abstract: An input buffer circuit includes an output circuit and supplies a plurality of signals in response to an input signal. A delay line is constituted of a plurality of delay cells connected in series and delays the signals supplied from the input buffer circuit. A PLL circuit connected to the delay line, includes a level converter which outputs a control signal for controlling a delay time of the delay line. An output signal generation circuit generates a signal having a multiplied frequency from the output signal of the input buffer circuit and the output signal of a tap of the delay line. Each of the delay cells has an output circuit having the same arrangement as that of the output circuit provided in the input buffer circuit, and a clocked inverter circuit included in each of the output circuits of the delay cells and input buffer circuit is controlled by the control signal output from the level converter.

Abstract: The invention discloses a method and an apparatus for implementing an L phase clock in conjuction with L counters, where L is an integer, to count at a frequency scalable by L.

Abstract: A clock signal generator for creating an output clock signal with fifty percent duty cycle and multiple of the input clock signal frequency allows generation of such a signal independent of input signal frequency and duty cycle. The generator utilizes an adjustable-delay oscillating feedback loop. A serial array of propagating delay elements measure the period of the input clock signal by triggering on successive input clock signal leading edges. This propagation lengthens the oscillating feedback loop until the output signal matches the desired frequency multiple. The feedback loop automatically adjusts according to a predetermined fraction of the period of the input clock signal. A fixed ratio of feedback loop delay to serial array delay ensures an output signal with a desired frequency multiple of the input signal frequency. Incorporation of an inverting logic gate in the oscillating feedback loop ensures a half-wave output clock signal having a fifty percent duty cycle.

Abstract: A circuit (10) for generating an output signal having a frequency that is a multiple of an input clock signal (CLKIN). The circuit includes a delay circuit (12) having an input port and a plurality of output ports (A,B,C). The input port is coupled during use to the input clock signal. Individual ones of the plurality of output ports output a signal that is delayed with respect to the input clock signal and also with respect to others of the plurality of output ports. The circuit further includes a logic network (20) having a first input for coupling to the input clock signal and a plurality of second inputs for coupling to the plurality of output ports. The logic network operates to logically combine signals emanating from the plurality of output ports with the input clock signal, and has an output port (OUTPUT) for outputting a signal having a frequency that is multiple of a frequency of the input clock signal.

Abstract: A counter and/or divider arrangement, comprising at least two subsidiary counter circuits, each of which comprises a number of flipflops which are concatenated in respect of their data inputs and outputs, all subsidiary counter circuits receiving a common clock signal, and also comprising at least one logic element, enables the implementation of arbitrary counting operations or division ratios with a low expenditure as regards circuitry and with low-noise operation in that in each logic element signals from the data output of one of the flipflops of at least a part of the subsidiary counter circuits are combined in conformity with an AND-function so as to form an associated resultant signal, each of the resultant signals being applied to at least one of the subsidiary counter circuits as a reset signal in order to switch the subsidiary circuit to an initial state, an output signal being formed from at least one of the resultant signals, the product of the total numbers of flipflops of all subsidiary counter c

Abstract: In a circuit for dividing the frequency of a received signal by an uneven number, initially another signal is derived through half-integer frequency division and thereafter divided by two. Preferably, a frequency division is performed alternately by an integer under the half-integer and by an integer above the half-integer, in order to achieve frequency division by a half-integer, whereby the toggling is performed dependent on the output signal.

Abstract: A multiplication circuit of minimized transfer error having a selector for inputting analog data to one of a plurality of sample hold circuits. The data input in the sample hold circuit is introduced to one of a plurality of multiplication circuits by a multiplexer with multi-input and -output. Data is not transferred between adjacent sample hold circuits.

Abstract: A first odd-number frequency divider for frequency-dividing and outputting an input signal of optional frequency includes a counter having cascade-connected n [n=1, 2, 3] elements of flip-flop circuits for receiving an input signal and outputting a 1/[2n+1] frequency-divided signal, a register having cascade-connected n [n=1, 2, 3] elements of flip-flop circuits for shifting the 1/[2n+1] frequency-divided signal successively synchronously with the input signal, a latch circuit for holding a register output signal of the [n-1]th flip-flop circuit of the register synchronously with an inverted signal of the input signal, and a logic circuit for receiving an inverted latch output signal outputted from the latch circuit and a register output signal of the nth flip-flop circuit and outputting the 1/[2n+1] frequency-divided signal.

Abstract: A high-voltage generating circuit for use in a CRT display apparatus has a horizontal drive circuit which is supplied with a horizontal frequency signal synchronous with a horizontal synchronizing signal in an input signal, a high-voltage converter output circuit which can be turned on and off by an output signal from the horizontal drive circuit, and a flyback transformer connected to an output terminal of the high-voltage converter output circuit. A frequency multiplier connected between the horizontal drive circuit and a terminal supplying the horizontal frequency signal to the horizontal drive circuit multiples the frequency of the horizontal signal at the terminal by a multiplication factor variable depending on the frequency of the horizontal frequency signal.

Abstract: An apparatus for counting occurrences of a particular input during a plurality of succeeding periods. The apparatus comprises an input terminal for receiving the input, a toggle signal generating circuit for generating a periodic toggle signal to mark the plurality of periods, and a plurality of n counter cell circuits for effecting the counting in n bits. Each counter cell circuit generates at least a respective bit output, a respective toggle output, and respective carry output. The counter cell circuits are arranged in hierarchical order from a least-significant counter cell circuit to a most-significant counter cell circuit.

Abstract: An integrated circuit for frequency synthesis within a microprocessor. The integrated circuit includes at least one of n-bit Johnson counter being clocked by a clock internal to the microprocessor. The n-bit Johnson counter being coupled to odd-even logic which generates "2n-1" outputs having "even" and "odd" divide values. The odd-even logic is coupled to a multiplexor which is selected to pass a selected output to be fed back into the n-bit Johnson counter.

Abstract: A programmable clock divider in which a system reference clock signal is divided by a programmed integer value. A storage register stores a value equal to the desired divisor minus two. A stored value of zero results in a divide by two. The stored value is loaded into a compare register and a counter is implemented to count reference clock signals. The compare register value and the counter value are compared by a comparator logic circuit. When the two values are equal, a flip-flop is toggled to switch the prescale clock value output. The flip-flop control logic includes circuitry for ensuring that odd divides exhibit an output clock frequency having a 50/50 duty cycle by controlling the flip-flop toggle to coincide with system clock edges. The flip-flop control logic also controls the timing for loading and resetting the compare and counter logic, respectively.

Abstract: A circuit for generating a pair of quadrature output signals from a pair of quadrature input signals in which the frequency of the output signals is double that of the input. The circuit consists of two dual phase shifters, two symmetrical multipliers and a phase controller. The circuit is fabricated by conventional integrated circuit processing technology. A method of generating frequency doubled quadrature output signals is disclosed.

Abstract: A divider circuit provides an output signal having a frequency which is equal to the frequency of an input signal divided by an odd integer. This is achieved by feeding back the output from a binary counter through an AND gate, delay flip-flop and an OR gate so that one cycle is added the output of the binary counter.

Abstract: A programmable clock divider in which a system reference clock signal is divided by a programmed integer value. A storage register stores a value equal to the desired divisor minus two. A stored value of zero results in a divide by two. The stored value is loaded into a compare register and a counter is implemented to count reference clock signals. The compare register value and the counter value are compared by a comparator logic circuit. When the two values are equal, a flip-flop is toggled to switch the prescale clock value output, The flip-flop control logic includes circuitry for ensuring that odd divides exhibit an output clock frequency having a 50/50 duty cycle by controlling the flip-flop toggle to coincide with system clock edges. The flip-flop control logic also controls the timing for loading and resetting the compare and counter logic, respectively.

Abstract: A signal generator includes a frequency divider having an input node for receiving a first signal having a first frequency f.sub.1 and a single output node for outputting a second signal having a second frequency f.sub.2, wherein a ratio f.sub.1 /f.sub.2 is equal to an odd number that is equal to or greater than three. A synchronous delay circuit has an input node coupled to the single output node of the frequency divider and an output node for outputting a third signal that is delayed in time with respect to the second signal by an amount that is a function of a period of the first signal. Logic is provided having a first input node coupled to the single output node of the frequency divider and a second input node coupled to the output node of the delay circuit. The logic has an output node for outputting a fourth signal having the second frequency f.sub.2 and a 50% duty cycle.

Abstract: A frequency doubler having adaptive biasing includes one shot circuits 10 and 12, which are responsive to particular transitions of an input signal for generating pulsed signals at each such transition. The widths of the pulses are determined by the magnitude of a bias current supplied to the one shot circuits. The pulsed signals of one shot circuits 10 and 12 are combined by OR gate 14 to provide an output signal whose frequency is twice the frequency of the input signal. A low-pass filter 16, coupled to the output signal, produces a signal which is a measure of the average voltage level of the output signal. Voltage-to-current converting FET 18, responsive to the average voltage level of the output signal, supplies bias current to one shots 10 and 12. Comparators 20 and 22 detect when the average voltage level is not within a predetermined range, and enable either up or down counting of digital counter 24.

Abstract: A basic clock signal generating circuit for use in a single chip microcomputer includes a frequency divider receiving an external clock signal for generating a frequency-divided clock signal, and a waveform shaping circuit receiving the frequency-divided clock signal output so as to generate a waveform-shaped frequency-divided clock as a basic clock of single chip microcomputer. An original oscillation clock generation circuit receives the external clock signal and generates an original oscillation clock having a frequency which is a-double of that of the basic clock. The basic clock and the original oscillation clock can be supplied to a peripheral circuit so that either the basic clock or the original oscillation clock can be selectively used in an internal circuit of the peripheral circuit.

Abstract: A phase lock loop monitors a first digital signal and generates a second digital signal operating substantially at frequency and in-phase with the first digital signal. A programmable divider latches a program integer for providing a latch integer, compares the latch integer to a constant integer, and generates a flag signal having a first state when the latch integer mismatches the constant integer and a second state when the latch integer matches the constant integer. The latch integer is decremented when the flag signal has the first state. The flag signal is delayed in response to first and second clock signals for providing the second digital signal having a frequency determined by the program integer. The first and second digital signals are applied to a lock detection circuit for providing a lock detection signal.

Abstract: An integrated circuit, such as a microprocessor or math coprocessor, having a clock generator circuit for generating a high frequency internal clock signal based on an external input signal is disclosed. A clock generator circuit comprises circuitry for detecting an active edge of an input signal, circuitry for generating a plurality of clock edges responsive to the detection of the clock signal and circuitry for inhibiting the edge generating circuitry after generation of a predetermined number of clock edges. The factor by which the input clock signal is multiplied may be set by the circuit designer, or programmably set, without impact on the circuit design. Hence, a single circuit may be used to generate clocks of various frequencies. Further, the duty cycle of the generated clock is independent of the input clock signal.

Abstract: A method and apparatus for improving the speed of response and display accuracy of a periodic input signal, of the type having a widely variable frequency, on an analog gauge have a meter deflection representative of the frequency of the input signal. Frequency scaling means are provided for multiplying the frequency of the input signal by a first constant to generate an intermediate signal. Counting means are coupled to the frequency scaling means for counting the frequency of the intermediate signal for a time period which is directly proportional to the maximum sweep deflection arc of the gauge times a second constant, and is inversely proportional to the maximum expected frequency of the input signal. Meter driver means coupled to the counting means are provided for deflecting the meter proportional to the counted intermediate signal frequency.

Abstract: A front end scalar to a frequency multiplier such as a synchronous delay line (SDL) allows the SDL to operate at a single clock frequency for all multiplier coefficients and input frequencies and provides for maximum SDL design margins. A frequency multiplier of this type relies upon a feedback voltage to maintain a desired output clock frequency. So long as the input clock frequency is within predetermined limits, the feedback voltage will maintain the output frequency at a desired frequency for which the SDL has been optimized. As the input frequency approaches the upper or lower limit for which an SDL basic building block has been optimized, it may become impossible for an SDL to provide frequency lock since control voltage is already below or above V.sub.cc /2 due to a lower or a higher input frequency.

Abstract: The programmable clock circuit of the present invention provides the means to generate lower frequency clock signals from a higher clock frequency signal while maintaining the synchronous relationship of the signals as well as compatible electrical characteristics of the signal. The advantages to the circuit are realized in a system in which the processor core operates at a first higher frequent clock frequency while components coupled to the processor, such as memory, operate at a lower frequency. In order to maintain electrical and timing compatibility, it is desirable to derive the lower clock frequency used to communicate with external components from the clock frequency utilized by the processor core. In the clock circuit of the present invention, the high frequency input clock signal is input to the clock circuit which has the ability to generate multiple lower frequency output signals. The actual signal output is programmable to conform to system clock requirements.

Abstract: According to the frequency multiplier of the present invention, an output clock signal of multiplied frequency is emitted from an exclusive NOR circuit which enters an input clock signal and a signal obtained by delaying the input clock signal via a first delay circuit. To the first delay circuit, second and third delay circuits are sucessively cascaded to delay the input clock signal. A circuit which comprises two flip-flops is supplied with the input clock signal and the output of the third delay circuit to emit a set signal when the rise in output of the third delayed circuit becomes faster than the fall of the input clock signal due to change in the delay time caused by the external conditions.

Abstract: A method and apparatus for providing a lower frequency signal with reference to a higher frequency signal are disclosed. The apparatus of the invention comprises an oscillating signal generator, an integer logical divider, and a signal combiner. The signal generator receives an input voltage and, in response thereto, generates a first output oscillating signal and a second output oscillating signal, both having a first frequency. The two oscillating signals are separated by a ninety-degree phase shift. The integer logical divider receives the two oscillating signals and provides two output divided signals in response. The first divided signal is representative of the first oscillating signal except that its frequency is one-third the frequency of the first oscillating signal. Likewise, the second divided signal is representative of the second oscillating signal except that its frequency is one-third that of the second oscillating signal.

Abstract: Conventional microprocessors await the data on the bus for acceptance for a given number of processor clock signals after accessing an external device, notably after a read instruction for an external data memory. When a comparatively slow memory is used in conjunction with a fast microprocessor, it may occur that the data is not yet present at the anticipated instant. In microprocessors in which no hold state is provided it is known to reduce the clock frequency during the reading of the external memory until the data is actually available. However, this results in a fluctuating mean clock frequency of the microprocessor so that internal timing members, controlled by the clock, cannot determine defined periods of time. In accordance with the invention, the clock frequency is reduced during the part of the operating cycle of the microprocessor during which an external device can be accessed, the microprocessor operating at the maximum clock frequency during the remainder of the cycle.

Abstract: A doubling circuit for adjusting the duty ratio of an output signal automatically and implemented as a digital circuit. A variable delay circuit delays an input signal while an exclusive-OR (EOR) gate produces EOR of the output signal of the delay circuit and the input signal. The resulting output of the EOR gate has a frequency double the frequency of the input signal. A low pass filter (LPF) filters the output signal of the EOR gate to produce a means voltage thereof. An integrating circuit integrates a difference between the output voltage of the LPF and a reference voltage. The delay of the variable delay circuit is controlled by the output of the integrating circuit. As a result, the doubled signal from the EOR gate has the duty ratio thereof automatically adjusted.

Abstract: A dividing ratio is represented by a ratio (M/N) of two integers (M) and (N), and six data (N), (-N), (M), (M+N), (M-N) and (0) are generated, then one of the six data is selected on the basis of a condition that is predetermined by an input signal to be divided and a comparison result of the data (N), (-N) and data which is derived by addition or subtraction between the selected data from the six data and the previous calculation result of the addition or subtraction; and output or interception of an output signal is controlled on the basis the comparison result, and thereby the input signal is divided by the dividing ratio (M/N).

Abstract: A clock generator is described for generating an output clock frequency from an input clock frequency where the frequencies of the clocks are not integrally related. The division process is designed using the quotients of the Euclidean theorem for determining the greatest common divisor of two integers in such a way as to alleviate the adverse effects of jitter. Applications to oversampled sigma-delta codecs are described.

Abstract: An improved direct digital frequency multiplier that multiplies input frequencies by a factor equal to the number of comparators in the circuit divided by two. The circuit includes a sensing stage, a ramping stage, a storage stage, a comparison stage and a logic stage. A signal containing the frequency to be multiplied is input to the sensing stage, which determines the frequency of the signal and outputs timing signals to the rest of the circuit. Coinciding with the period of the input signal, ramping voltages are generated, whose peak voltages are sampled and held for a specific time. The linearly ramping voltages are compared with the peak voltages and the comparison stage outputs voltage spikes to the logic stage. The logic stage combines the outputs from the comparison stage, and outputs a square wave signal possessing the appropriate multiplied frequency.

Abstract: A low-skew CMOS clock divider circuit for providing tracking of the divide-by-one and divide-by-two output signals obtained from a source of master clock pulses is fabricated using two matched flip-flops externally wired as divide-by-two devices. Coincidence gates are coupled with the outputs of the flip-flops to produce the desired divide-by-one and divide-by-two output signals in a manner such that the signals in each path pass through substantially identical circuit components, Thus, any delays encountered are the same in both circuit paths. In this manner, skew between the edges of the divide-by-two and divide-by-one clock signals is significantly reduced.

Abstract: A semiconductor integrated circuit of this invention includes an oscillation circuit formed on a semiconductor substrate, a frequency dividing circuit formed on the semiconductor substrate, for dividing a frequency of an oscillation output from the oscillation circuit, clocked inverters for selectively permitting one of an original oscillation frequency signal of the oscillation circuit and outputs of the frequency dividing circuit to pass therethrough, an output circuit for outputting a signal selected by the cocked inverters, and a frequency dividing circuit controlling NAND circuit for interrupting the operation of the frequency dividing circuit while the original oscillation frequency signal of the oscillation circuit is being output from the output circuit.

Abstract: A fractional divider using a counter means to provide fractionality. A divider is used to divide the VCO output signal by N or N+1 as selected. A divider control circuit controls the divider to divide by the appropriate divisor to obtain the selected output frequency. The fractional divider circuit counts divider control signals which represent a first division period. The fractional divider circuit establishes a second period of multiple first periods and at the terminal count of each second period, provides a selected number of fractional control signals to the divider control to cause division by a different number, such as N+1. The fractional divider comprises a first counter programmed to count first periods and issue its terminal count upon receiving the programmed count of first periods. The fractional divider also comprises a second counter to provide the selected number of fractional control signals upon receipt of the terminal count of the first counter.

Abstract: A high speed modular counter (100) utilizing a novel counting method in which the first bit changes with the frequency of the driving clock, and changes in the higher order bits are initiated one clock pulse after a "0" to "1" transition of the next lower order bit. This allows all carries to be known one clock period in advance of a bit change. The present counter is modular and utilizes two types of standard counter cells. A first counter cell determines the zero bit. The second counter cell determines any other higher order bit. Additional second counter cells are added to the counter to accommodate any count length without affecting speed.

Abstract: A serial-parallel converting circuit comprises a four-stage shift register circuit receiving a serial data so as to shift the received serial data through the shift register in response to each clock signal, and an output register circuit coupled in parallel to respective stages of the shift register circuit so as to fetch the content of the shift register circuit in response to a frequency-divided clock supplied from a frequency dividing circuit. The frequency dividing circuit receives the clock signal through an inverter and is composed of only two D-type flipflops and one inverter. Each of the D-type flipflops has a clock input connected to receive the clock signal in common, and the D-type flipflops are connected in series to form a shifter register. A Q output of a second flipflop is connected through the inverter to a data input of a first flipflop, so that the Q output of the last flipflop generates the frequency-divided signal.

Abstract: The electronic counter for counting a periodic clock signal generated at a preset clock frequency (f.sub.o) includes a clock circuit generating the periodic clock signal at the preset clock frequency (f.sub.o); an adjustable frequency divider (4) having an output (8), a first input (5) and a second input (7), the first input of the frequency divider (4) being connected to the clock circuit (6) so as to receive the periodic clock signal and the second input (7) of the frequency divider being connected to receive a cycle speed signal (n), the frequency divider (4) containing means to produce a pulsed output signal at a divider output frequency (c.sub.o); a tracking circuit (T) connected to the output (8) of the frequency divider (4) to receive the pulsed output signal at the divider output frequency (c.sub.

Abstract: A high resolution digitally controlled oscillator is in the form of a digital frequency divider, which uses calculation logic to utilize both the rising edge and the falling edge (start edge and stop edge) of the input clock pulses to provide the capability of alternating between two adjacent frequencies. This results in significantly improved resolution, since the division ratio is not dependent upon any integral number of clock periods.

Abstract: Judgment means provides a first output alternating signal to a .div.2 frequency-divider and also a frequency-division control signal at a first level to operate the .div.2 frequency-divider, when a first input alternating signal is applied to an input terminal. The first output alternating signal frequency divided by the .div.2 frequency divider is applied to an NOR gate, to which a first gate control signal is applied from the judgment means so as to allow the frequency divided first output alternating signal to pass the NOR gate. When a second input alternating signal is applied to the input terminal, the judgment means provides the frequency-division control signal at a second level to the .div.2 frequency-divider which, in turn, provides a second gate control signal to the NOR gate. At this time, the judgment means also provides a second output alternating signal to the NOR gate. The NOR gate with the second gate control signal applied thereto passes the second output alternating signal therethrough.

Abstract: A frequency discriminating circuit suitable for use with a display capable of displaying image data of a plurality of signal formats and which has an oscillator for generating an oscillation frequency corresponding to a horizontal synchronizing frequency of an input signal which can be displayed. This frequency discriminating circuit includes a counter for frequency-dividing the oscillation frequency of the oscillator which is reset by a horizontal synchronizing signal, to thereby discriminate the horizontal synchronizing frequency of the input signal.

Abstract: A frequency division scheme which offsets for a phase lag produced on initial power-on is described. A division ratio of a programmable counter is initially set at a first division ratio at the time of releasing the programmable counter from its reset state. When the first division cycle is complete, the division ratio is reset to its steady state value. Thus, a delay equivalent to the phase lag is produced. A frequency synthesizer is also proposed where the division ratio is set, and a phase difference is detected. Reset signals are continually set while the phase difference is changed. This cycle is continued until the phase difference is reduced to one cycle of the input signals or less.

Abstract: A programmable frequency dividing network comprises a plurality of cascade-connected programmable frequency dividing stages each of which divides the frequency of a clock pulse by two and three based on a logic level of a preset input signal used to change a variable division ratio from one to another. In addition, there is provided a gating means for determining or detecting whether or not each of the outputs of programmable frequency dividing stages of the programmable frequency dividing network after a programmable frequency dividing stage as a second stage is brought to a predetermined pattern and an instruction signal for making a decision as to the division of the division ratio by (+1) is inputted, so as to generate the output of a logic level for causing a programmable frequency dividing stage equivalent to a first stage to divide the frequency of the clock pulse by three if it is determined to be positive in the above detection process.

Abstract: A counter/divider dividing an input frequency (F1) by 2.sup.q+n +1/2, comprises a first divider by 2.sup.q (30) receiving the signal to divide of a frequency F1 and provides 2.sup.q+1 outputs at the frequency F1/2.sup.q out of phase the ones to the others of 360.degree./2.sup.q+1 ; a multiplexer (32) having a control terminal (34) and sequentially providng at its output (33) each of said 2.sup.q+1 outputs each time a control signal is applied; and a second divider by 2.sup.n (31) receiving the output (33) of the multiplexer and providing the desired output (34) of the counter/divider, this output being applied to the control terminal of the multiplexer.

Abstract: A variable frequency dividing circuit according to this invention switches a frequency division ratio immediately after a neew frequency division ratio has been input, and then performs a frequency dividing operation without discarding already counted values. This frequency dividing circuit generates an error signal if a newly input frequency division ratio differs from the previous frequency division ratio and the already counted value is larger than the new frequency division ratio. Furthermore, the frequency dividing circuit performs forcibly a frequency division completion processing according to the consecutively input frequency signal.

Abstract: A method divides a recurrent digital clocking signal into a quotient digital signal having a substantially symmetrical duty cycle within a range of programmable quotients, the quotients being selectable in single increments of the recurrent digital clocking signal within a range as selected by a divisor.

Abstract: A first frequency dividing circuit receives an input clock signal from an input terminal and divides the frequency of the input clock signal to produce a first signal which it supplies to an output terminal. A second frequency dividing circuit divides the frequency of the input clock signal to produce a second signal having the same frequency as the first signal but differing from the first signal in phase. The second signal controls a gating circuit. When switched on, the gating circuit connects the output terminal to the input terminal, or to an auxiliary power-supply or ground terminal, thereby deskewing the signal at the output terminal.

Abstract: A frequency divider includes at least three master-slave flip-flops which are connected to each other in stages, each stage including a master flip-flop and a slave flip-flop, to construct a 1/N frequency divider. At least two outputs whose periods are the same but phases are different are taken out from a master flip-flop and a slave flip-flop and combined to obtain a 1/(N/2) divided output signal. As a result, a divided output signal whose period does not vary with time is obtained and, when the N is an even number, an output signal with a duty ratio of 1/2 is obtained. A pulse signal former includes a differential amplifier to which two signals whose periods and pulse widths are the same but phases are shifted by a pulse width and an output obtained by comparing those two signals is output from the pulse signal former. As a result, an output signal whose duty ratio is 1/2 is obtained.

Abstract: A clock pulse generator for a one-chip microprocessor permits the microprocessor to be operated on two different power sources by effectively using a single source of clock pulses, a clock pulse divider and gate circuits to gate a specific sequence of pulses to the microprocessor. The period of a slowest clock pulse signal after division is integrally related to the periods of the faster clock pulse signals so that the pulse signals are synchronously provided.

Abstract: A monostable multivibrator having a time constant that is approximately one-quarter of the period of a pulse signal supplied to its input is used for frequency doubling of a 50% keying ratio input pulse signal. The output signals of the multivibrator are low-pass filtered and supplied to inputs of a different amplifier operating as a difference integrator by virtue of a capacitance connected between its output and its inverting input. This output is utilized to modify the time constant when the period of the input pulse sequence becomes more than about four times the time constant of the multivibrator, thus keeping the keying ratio of the output signals at 50% over a wide range of variation of the frequency of the usually symmetrically input pulse sequence. The multivibrator is connected so as to be triggered by both rising and falling flanks of the input pulses. Both ECL and TTL embodiments are shown.

Abstract: A circuit configuration for improving the resolution of successive pulsed signals over time includes first and second counters each having one clock input, the clock input of the first counter being supplied with a first clock signal, and the clock input of the second counter being supplied with a second clock signal having a n-multiple frequency of the first clock signal. The first counter has a control input and a counter output, the control input of the first counter being supplied with successive pulsed signals. The second counter has a counter input, an overflow output and a write input, the write input of the second counter being connected to the overflow output of the second counter.

Abstract: A frequency divider uses a single D flip-flop integrated circuit having an inverted output and an asynchronous clear input between which a feedback loop comprising a delay Tau is connected. The frequency divider receives a multi-GHz input frequency f.sub.1, and divides by any integer N to produce an output frequency f.sub.2 =f.sub.1 /N using the internal delay of the D flip-flop between input and output (CK-to-Q), and the internal delay between the asynchronous clear input to the output (CLR-to-Q). Solving for the amount of delay Tau in the feedback loop necessary to produce the desired integer, or divide ratio, N, according to a predetermined formula is also required. An integrated circuit D flip-flop manufactured by Gigabit Logic is preferably selected to provide the high input frequency capability, external to which is added the feedback loop for determining the divide ration desired. The divide ratio, or integer by which the input frequency is divided, includes the ability to divide by a non-2.sup.