Abstract: An Integrated Circuit includes a target circuit, first and second logic chains, a feedback path and calibration circuitry. The target circuit includes first and second inputs. The first and second logic chains propagate a signal from a common input point to the first and second inputs of the target circuit, respectively. The feedback path receives the signal from the first or second input and feeds the signal back to the common input point. The calibration circuitry is configured to connect the first input to the feedback path thereby forming a first closed-loop oscillator circuit, and measure a first oscillation frequency of the first closed-loop oscillator circuit, connect the second input to the feedback path, thereby forming a second closed-loop oscillator circuit, and measure a second oscillation frequency of the second closed-loop oscillator circuit, and verify a timing constraint responsively to the first and second oscillating frequencies.

Abstract: A latch circuit for retaining and transmitting an input data value is disclosed, along with a memory, and a method for retaining and transmitting data. The latch circuit includes a primary input for receiving a data value, an output for outputting the data value, a data transmission path including a transmitting device for transmitting the data value from the primary input to the output, a feedback loop for retaining the data value, the feedback loop including the transmitting device and a further device. The further device is configured to turn on in response to assertion of an activating signal and to turn off in response to no assertion of the activating signal.

Abstract: Edge-sensitive Feedback-controlled pulse generator. A circuit includes a pulse generating circuit responsive to a desired transition in an input signal to initiate an output pulse. The circuit also includes a delay circuit responsive to the output pulse to generate a feedback signal. Further, the circuit includes a first latch that renders the pulse generating circuit unresponsive to any change in the input signal until the feedback signal has been generated, a switch responsive to the feedback signal to complete the output pulse, a second latch responsive to a change in the input signal after the feedback signal has been generated to render the pulse generating circuit responsive to a subsequent occurrence of the desired transition in the input signal to initiate the output pulse again, and a third latch responsive to the change in the input signal after the feedback signal has been generated.

Abstract: A method of generating an output signal from an input signal includes a step of generating a set of n signals, n being an integer greater than or equal to 3, by generating a signal for each integer i such that 0?i?(n?1), each signal within the set having the same frequency and approximately equal amplitude and a phase equal to (360/n)i degrees. The method also includes a step of inputting each of the set of n signals to a gate terminal of a corresponding one of a set of n transistors. Each of the transistors has a source terminal electrically connected to a common voltage drain and each of the transistors has a drain terminal electrically connected to a coupling. The coupling is electrically connected to a common voltage source. The output signal at the coupling has a frequency equal to the frequency of the input signal multiplied by n.

Abstract: Input circuitry is provided for a high voltage operated radiation detector to receive pulses from the detector having a rise time in the range of from about one nanosecond to about ten nanoseconds. An integrator circuit, which utilizes current feedback, receives the incoming charge from the radiation detector and creates voltage by integrating across a small capacitor. The integrator utilizes an amplifier which closely follows the voltage across the capacitor to produce an integrator output pulse with a peak value which may be used to determine the energy which produced the pulse. The pulse width of the output is stretched to approximately 50 to 300 nanoseconds for use by subsequent circuits which may then use amplifiers with lower slew rates.

Abstract: A fast latch including: a NAND stage adapted to receive a clock signal and a data input signal; a clocked inverter stage, a first input of the clocked inverter stage coupled to the output of the NAND stage and a second input of the clocked inverter stage coupled to the clock signal; a first inverter stage, a first input of the first inverter stage coupled to an output of the clocked inverter and a second input of the first inverter stage coupled to a reset signal; and a second inverter stage, having an output, an input of the second inverter stage coupled to an output of the first inverter stage. The fast latch is suitable for use in frequency divider circuits also described. A homologue of frequency dividers using the fast latch, a unique 3/4 divider and a 2 divider not using the fast latch are also disclosed.

Abstract: A circuit for capturing data from a bus having a flip-flop register, comparison logic and clock logic. The comparison logic determines whether any bit on the bus has changed logic state. If a bit has changed state, the comparison logic asserts an enable signal which causes the clock logic to clock the register. Accordingly, data from the bus is not clocked through the register unless the data has actually changed state and the comparison logic itself determines whether different data is present on the bus.

Abstract: A calibration and adjustment system for post-fabrication control of a delay locked loop charge pump current is provided. The calibration and adjustment system includes an adjustment device that varies an amount of charge pump current. Such control of the charge pump current in a delay locked loop allows a designer to achieve a desired delay locked loop operating characteristic after the delay locked loop has been fabricated. A representative value of the amount of adjustment desired in the charge pump current may be stored and subsequently read to adjust the delay locked loop.

Abstract: An adjustment technique allowing easy adjustment of a phase shifter is disclosed. A programmable device (PLD) is connected to the phase shifter so as to correct a standard vector depending on correction data written thereto. When supplying a standard input signal to the phase shifter, the phase and amplitude of the output signal are measured. A standard vector for a sequentially selected one of a plurality of phase points is generated and outputted to the phase shifter. Correction data for a selected phase point is calculated based on the measured phase and amplitude. A VHDL source program is generated from the corrected data for all the phase points to write the correction data into the PLD.

Abstract: A latch device having a selectable feedback path includes a retaining device and system isolation device. The retaining device retains within the feedback path a logical value to be written out. The logical value is latched during an active clock signal. The system isolation device disconnects the retaining device from the feedback path during a write operation. Then, when the logical value is written out, the system isolation device reconnects the retaining device. Thus, the feedback path of the latch device may be disconnected to allow for a change in the latch state without overdriving a feedback inverter.

Abstract: An input signal SIN is input to a reset input terminal R of a flip-flop RSFF1 and, at the same time, input to a gate of a pMOS transistor MP1 constituting a transfer control circuit DCNTL1, a signal Bd obtained by delaying an inverted output signal B of the flip-flop RSFF1 at a delay circuit DLY1 is input to the data input terminal of the transfer control circuit DCNTL1, and the output signal of the transfer control circuit DCNTL1 is input to a set input terminal S of the flip-flop RSFF1 via two stages of inverters connected in series, therefore, a signal change detection circuit capable of generating a stable pulse according to the level change of the input signal without depending upon the input clock signal and capable of generating the pulse at high speed can be realized.

Abstract: A phase-locked loop of the type including a locking aid circuit providing a d.c. presetting signal representative of the carrier frequency of an input signal to set the quiescent frequency of a controlled oscillator of the phase-locked lop. The locking aid circuit includes a monostable latch clocked by the input signal to provide pulses of predetermined width, the presetting signal corresponding to the mean value of these pulses.

Abstract: A self-resetting logic stage provides for a relatively faster propagation of pulse signals and for relatively less power consumption. For a self-resetting logic stage in a digital logic path of successive logic stages, a forward path creates the forward edge for an output pulse signal and a reset path creates a reset or trailing edge for the output pulse signal. The propagation delay for the reset path may be increased for successive stages in the logic path to minimize or avoid overlap current. As the increased propagation delay increases the width of a pulse signal as the pulse signal propagates from stage to stage, logic stages in the logic path may be configured to reduce the width of the pulse signal, for example when the pulse signal approaches a width that may limit the cycle time for the logic path. Logic stages in the logic path may also be configured to provide for relatively quicker reset recovery to minimize any increase in cycle time.

Abstract: A power short pulse generator for generating a pulse on a rising edge and falling edge of an input signal according to the present invention comprises an input node for receiving the input signal and an output node for supplying an output signal. A first pulldown circuit and a second pulldown circuit are connected in series between the output node and a first supply voltage potential, the first pulldown circuit and the second pulldown circuit each having an input. A third pulldown circuit and a fourth pulldown circuit are connected in series between the output node and the first supply voltage potential, the third pulldown circuit and the fourth pulldown circuit each having an input. A pullup circuit is connected between the output node and a second supply voltage potential, the pullup circuit having an input. A leakage current circuit is connected between the output node and the second supply voltage potential.

Abstract: A NAPNOP circuit for decreasing energy consumption of all or a portion of a microprocessor based system which includes a delay circuit for inhibiting or slowing the output of the system clock pulses for a variable length of time equal to a multiple of N clock pulses where N is a positive integer. The NAPNOP circuit has an input element for inputting a STARTNAP signal which begins a nap period during which the system clock pulses are inhibited or slowed, a clock input device for providing a plurality of selectable clock pulses as inputs to the delay circuit for controlling the operation of the computer system, and a gate element for terminating the nap period.

Abstract: A low power flip-flop circuit is disclosed including a clocked flip-flop (10) and switching circuit (40, 60) with control inputs coupled to the data input and data output of the flip-flop to determine whether or not the data input to the flip-flop is changing. Any clock pulse during periods when the data input is not changing consumes power without providing a useful function. The switching circuit passes clock pulses to a clock input of the flip-flop only when new data is present to be latched into the flip-flop, i.e. data input state and data output state disagree. The switching circuit blocks clock pulses to the flip-flop when the data to the flip-flop is not changing and thereby saves power consumption.

Abstract: An integrated circuit one shot circuit provides relatively long duration (hundreds of nanoseconds up to a millisecond) output pulses without the need for excessively large transistors. The one shot circuit includes a pull up and a pull down device connected to the one shot circuit's input terminal, with a latch connected to a node between the pull up and pull down devices. The output terminal of the latch is connected to the input of a Schmitt trigger. One terminal of a grounded capacitor is connected between the latch output terminal and the Schmitt trigger input. The output terminal of the Schmitt trigger is connected through an inverter to one input terminal of a NAND gate, the other input terminal of which is connected to the one shot circuit's input terminal. A feedback line connects the output terminal of the NAND gate to the gate of a depletion mode transistor which is between the pull up and pull down devices.