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有些示波器提供一个主时基和两个延迟时基.这些示波器使用户能在主时基上观察两个高分辨率的时间窗口.触发后这些窗口可以定位在任何地方,还按扫描旋钮设定的新采样速率进行全新的信号采集.新采样速率比主采集所用的采样率高得多.这种能力可用来显示随地址而变化的RAM存取时间(见图a).在该例中,上面两个扫迹表示按50ns/div扫速采集的通道1和通道2信号.等效采样率为2GS/s.第三扫迹是通道1显示的延迟时基窗口.它使用1ns/div的分辨率,而等效采样速率是20GS/s.这个窗口从触发点开始,大约显示270ns.在第三个扫迹的上升时间瞬变中可以见到好几条线,这些线对应不同的存取时间.两条原始扫迹给出波形的全景,而由延迟时基提供的时间分辨率能使我们看到寻址时间频谱.应用两个延迟时基的一个例子,涉及到一连串的微处理器活动(扫迹A)和相关联的存储器寻址活动即扫迹B.这些扫迹的采样率为2GS/s,分辨率为0.2μs/div.所需的时间间隔测量是从扫迹A的第一个上升沿到扫迹B的最后
Some oscilloscopes provide a master time base and two delay time bases that allow the user to view two high-resolution time windows on the master timebase, which can be positioned anywhere after the trigger, and also set by pressing the scan knob Of the new sampling rate for a new signal acquisition.The new sampling rate is much higher than the sampling rate used by the main acquisition.This ability can be used to display the RAM address change access time (see Figure a) In this case, The two traces above represent the channel 1 and channel 2 signals acquired at 50ns / div, the equivalent sample rate is 2GS / s, and the third trace is the delay timebase window shown on channel 1. It uses 1ns / div Resolution, while the equivalent sample rate is 20GS / s. This window, starting at the trigger point, shows approximately 270ns. Several lines can be seen during the rise time transients of the third trace, which correspond to different accesses Time. Two original traces give a panoramic view of the waveform, and the temporal resolution provided by the delay time base allows us to see the time-of-day spectrum. An example of applying two delay time bases involves a series of microprocessors Activity (Trace A) and associated memory addressing B. These dynamic i.e. the trace of the trace sampling rate of 2GS / s, with a resolution of 0.2μs / div. Time interval required for measuring the trace from the first rising edge of A to the end of the trace B