Abstract: A system for calibrating cables attached to a time measurement device is disclosed. The system includes a calibration device that generates a plurality of synchronized measurement signals that are communicated to a time measurement device by a set of cables. The calibration device can also generate at least one arming signal that is also communicated to the time measurement device. By determining the relative arrival time of a common reference event of each of the measurement signals, the time measurement device can determine any skew that exists between each of the cables that input the measurement signals. The skew can then be used to compensate for varying cable skew in future time measurements. In one embodiment, the system of the present invention can also be used to determine the arming latency of the time measurement device by delaying the measurement signals in relation to the arming signals and observing the delay time which causes complete synchronization of the measurement signals.

Abstract: A method for calibrating cables attached to a time measurement device is disclosed. Such a method may utilize a system including a calibration device that generates a plurality of synchronized measurement signals that are communicated to a time measurement device by a set of cables. By determining the relative arrival time of a common reference event of each of the measurement signals, the time measurement device can determine any skew that exists between each of the cables that input the measurement signals. The skew can then be used to compensate for varying cable skew in future time measurements. In one embodiment, the method can also be used to determine the arming latency of the time measurement device and by delaying the measurement signals in relation to the arming signals and observing the delay which causes complete synchronization of the measurement signals.

Abstract: An improved method for calibrating threshold voltage levels on comparators corresponds to providing a dithered DC signal to one input and adjusting the threshold voltage on the other input in response to the comparator output. Such calibration may be necessary for comparator circuitry associated with measurement devices. A circuit to generate a dithered DC signal sums a precise DC value with a time-varying signal that has been modified, such as a rectified AC signal. During the calibration procedure, the internal threshold voltage is varied until no timing measurements are present. The difference between the determined optimum threshold voltage and the ideal voltage is stored in a system computer associated with the measurement device and used later in the measurement process to produce a precise threshold voltage input.

Abstract: A method for calibrating cables attached to a time measurement device is disclosed. Such a method may utilize a system including a calibration device that generates a plurality of synchronized measurement signals that are communicated to a time measurement device by a set of cables. By determining the relative arrival time of a common reference event of each of the measurement signals, the time measurement device can determine any skew that exists between each of the cables that input the measurement signals. The skew can then be used to compensate for varying cable skew in future time measurements. In one embodiment, the method can also be used to determine the arming latency of the time measurement device and by delaying the measurement signals in relation to the arming signals and observing the delay which causes complete synchronization of the measurement signals.

Abstract: A system for calibrating cables attached to a time measurement device is disclosed. The system includes a calibration device that generates a plurality of synchronized measurement signals that are communicated to a time measurement device by a set of cables. The calibration device can also generate at least one arming signal that is also communicated to the time measurement device. By determining the relative arrival time of a common reference event of each of the measurement signals, the time measurement device can determine any skew that exists between each of the cables that input the measurement signals. The skew can then be used to compensate for varying cable skew in future time measurements. In one embodiment, the system of the present invention can also be used to determine the arming latency of the time measurement device by delaying the measurement signals in relation to the arming signals and observing the delay time which causes complete synchronization of the measurement signals.

Abstract: Improved input circuitry for use in conjunction with measurement devices is disclosed. The subject input circuitry enables a single measurement device to take measurements on both single-ended and differential signal inputs. Software-implemented control signals can be programmed by a user or set to default values to select which type of input signal is to be measured. The input circuitry minimizes the use of electromechanical relays and other components or phenomena that may degrade the quality of the input signals, and also includes resistor networks to additionally help maintain signal integrity. A plurality of common programmable voltage sources is provided for use in accordance with select embodiments of the disclosed technology to serve as either termination voltages, threshold voltages, or both.

Abstract: An improved method for calibrating threshold voltage levels on comparators corresponds to providing a dithered DC signal to one input and adjusting the threshold voltage on the other input in response to the comparator output. Such calibration may be necessary for comparator circuitry associated with measurement devices. A circuit to generate a dithered DC signal sums a precise DC value with a time-varying signal that has been modified, such as a rectified AC signal. During the calibration procedure, the internal threshold voltage is varied until no timing measurements are present. The difference between the determined optimum threshold voltage and the ideal voltage is stored in a system computer associated with the measurement device and used later in the measurement process to produce a precise threshold voltage input.

Abstract: Improved input circuitry for use in conjunction with measurement devices is disclosed. The subject input circuitry enables a single measurement device to take measurements on both single-ended and differential signal inputs. Software-implemented control signals can be programmed by a user or set to default values to select which type of input signal is to be measured. The input circuitry minimizes the use of electromechanical relays and other components or phenomena that may degrade the quality of the input signals, and also includes resistor networks to additionally help maintain signal integrity. A plurality of common programmable voltage sources is provided for use in accordance with select embodiments of the disclosed technology to serve as either termination voltages, threshold voltages, or both.

Abstract: A time interval analyzer for measuring time intervals between events in an input signal includes a trigger circuit that receives the input signal and that outputs a time trigger signal at a first triggering level upon occurrence of a first input signal event. A time counter receives a time base signal and increments a time count at each period of the time base signal. The time count is calibrated to a predetermined reference time. A processor circuit is in communication with the trigger circuit and the time counter so;that the processor circuit receives the time trigger signal and reads the time count from the time counter. The processor circuit is configured to read the time count upon receiving the time trigger signal at the first triggering level so that the time count read by the processor circuit indicates the time at which the first input signal event occurred with respect to the predetermined reference time.

Abstract: A time interval analyzer includes a trigger circuit that receives an input signal and that outputs a trigger signal at a triggering level upon occurrence of a first event. A first counter receives the input signal and, when it is activated, increments a count at each occurrence of an event. A second counter receives the input signal and, when it is activated, increments a count at each occurrence of an event. A control circuit receives the trigger signal from the trigger circuit and outputs a control signal to each of the first counter and the second counter that controls activation of the first counter and the second counter so that only one of the first counter and the second counter is activated at a time.

Abstract: A time interval analyzer includes a signal channel that receives an input signal. A plurality of measurement circuits are defined within the signal channel in parallel with each other. Each measurement circuit is configured to receive the input signal, measure an occurrence of a first event of the input signal with respect to a predetermined time reference and to output a time signal corresponding to the measurement of the occurrence. A processor circuit is in communication with the signal channel. It is configured to receive and compare time signals from the measurement circuits to each other to determine a time interval between the first event measured by a first measurement circuit and an event measured by a second measurement circuit.

Abstract: A time interval analyzer for measuring time intervals between events in an input signal includes a trigger circuit that receives an input signal and that outputs a trigger signal at a triggering level upon occurrence of a first event and at a non-triggering level upon occurrence of a reference event that follows the first event. A first current circuit has a current source or a current sink. A second current circuit has a current sink or a current source. A capacitor and a shunt are operatively disposed in parallel with respect to the first current circuit. The shunt is disposed between the first current circuit and the second current circuit. The shunt receives the trigger signal and is selectable between conducting and non-conducting states so that the shunt is driven to the conducting state upon receiving the trigger signal at the triggering level and is driven to the non-conducting state upon receiving the trigger signal at a non-triggering level.

Abstract: A time interval analyzer for measuring time intervals between events in an input signal includes a trigger circuit that receives an input signal and that outputs a trigger signal at a triggering level upon occurrence of the event. A first current circuit has a constant current source or a constant current sink. A second current circuit has (1) a current sink where the first current circuit has a constant current source or (2) a current source where the first current circuit has a constant current sink. A capacitor and a shunt are operatively disposed in parallel with respect to the first current circuit. The shunt is disposed between the first current circuit and the second current circuit.