摘要:
A waveform digitizer particularly suitable for use in electronic test systems for analyzing and displaying analog signals is disclosed. A digitally derived reference voltage is compared with the analog signal to be digitized during a series of comparison sequences. Simultaneously with the start of each comparison sequence a digital clock is started. Each time the analog signal rises above, or drops below, the reference voltage a decision change detector produces an enable pulse. Each time an enable pulse occurs, a data word, having a portion related to the value of the digitally derived reference voltage and a portion related to the digital clock value, is stored and/or used to control a display. At the end of the first comparison sequence (determined when the digital clock value reaches a predetermined level) the reference voltage is incremented and a second comparison sequence started. These steps are repeated until the reference voltage reaches a predetermined level. The resulting set of digital words is a digitized equivalent of the waveform of the analog signal.
摘要:
The present application discloses a method and apparatus for determining resistance values of a dynamic voltage-adjusting circuit. The method includes: determining a reference voltage, a maximum output voltage value, and a minimum output voltage value of the dynamic voltage-adjusting circuit; determining, according to the reference voltage and the maximum output voltage value, a first relational expression between the reference voltage, the maximum output voltage value, and multiple resistors of the dynamic voltage-adjusting circuit, and determining, according to the reference voltage and the minimum output voltage value, a second relational expression between the reference voltage, the minimum output voltage value, and the multiple resistors; and determining a group of resistance values of the multiple resistors according to the first relational expression and the second relational expression. The group of resistance values determined thereby is a group of resistance values adapting to the reference voltage. By adjusting the resistance values of the multiple resistors to fit with the varying reference voltage, it is ensured that voltage values output by the dynamic voltage-adjusting circuit can fall within a same range when the reference voltage takes different values.
摘要:
A device for displaying an analog signal on a display screen (7) which is scanned by means of a line deflection generator (21) and a frame deflection generator (23). The device comprises a signal processing device (13) forforming a processed signal by repeating the analog signal at the line deflection frequency, a reference voltage generator (19) for generating a reference voltage which is dependent on the frame deflection voltage, and a comparator (17) for comparing the reference voltage and the processed signal and for generating a control signal which causes a brightening of the scanned display screen (7) when both signals are approximately equal. In order to improve the picture quality, the device comprises means (18) for adding a varying auxiliary signal to the processed signal. The frequency of this auxiliary signal amounts to at least ten times the line deflection frequency.
摘要:
A control device for an AC rotary machine includes an AC rotary machine having m sets of n-phase windings, a current detector, a power converter, and a control unit that calculates voltage commands on the basis of respective differences between a current command for the AC rotary machine and current detection values obtained by the current detector, and outputs ON/OFF signals to high potential side switching elements and low potential side switching elements of the power converter by comparing applied voltages calculated on the basis of the voltage commands with a carrier wave signal, wherein the current detector, when detecting currents flowing through the n-phase windings on the basis of currents flowing through current detection resistance elements that are inserted in series into the low potential side switching elements, obtains current detection values at two or more fixed timings over a single period of the carrier wave signal.
摘要:
The present application discloses a method and apparatus for determining resistance values of a dynamic voltage-adjusting circuit. The method includes: determining a reference voltage, a maximum output voltage value, and a minimum output voltage value of the dynamic voltage-adjusting circuit; determining, according to the reference voltage and the maximum output voltage value, a first relational expression between the reference voltage, the maximum output voltage value, and multiple resistors of the dynamic voltage-adjusting circuit, and determining, according to the reference voltage and the minimum output voltage value, a second relational expression between the reference voltage, the minimum output voltage value, and the multiple resistors; and determining a group of resistance values of the multiple resistors according to the first relational expression and the second relational expression. The group of resistance values determined thereby is a group of resistance values adapting to the reference voltage. By adjusting the resistance values of the multiple resistors to fit with the varying reference voltage, it is ensured that voltage values output by the dynamic voltage-adjusting circuit can fall within a same range when the reference voltage takes different values.
摘要:
The present application discloses a method and apparatus for determining resistance values of a dynamic voltage-adjusting circuit. The method includes: determining a reference voltage, a maximum output voltage value, and a minimum output voltage value of the dynamic voltage-adjusting circuit; determining, according to the reference voltage and the maximum output voltage value, a first relational expression between the reference voltage, the maximum output voltage value, and multiple resistors of the dynamic voltage-adjusting circuit, and determining, according to the reference voltage and the minimum output voltage value, a second relational expression between the reference voltage, the minimum output voltage value, and the multiple resistors; and determining a group of resistance values of the multiple resistors according to the first relational expression and the second relational expression. The group of resistance values determined thereby is a group of resistance values adapting to the reference voltage. By adjusting the resistance values of the multiple resistors to fit with the varying reference voltage, it is ensured that voltage values output by the dynamic voltage-adjusting circuit can fall within a same range when the reference voltage takes different values.