Measurement Tool for Fast Nonrepetitive Signals: Storage Oscilloscope
A storage oscilloscope, utilized for the measurement of fast nonrepetitive signals, is a specialized instrument. To assess the functionality of a digital storage oscilloscope, a tester generates two distinct signals. The first signal is a stepped voltage with superimposed glitches, offering a rapid assessment of the oscilloscope’s ability to eliminate glitches during signal processing. The second signal, a rectangular 2 kHz waveform with a superimposed 15 Hz analog signal, aids in verifying whether low-frequency signals remain clearly visible at a given setting. This check ensures the oscilloscope’s reliability and competence in handling signals, particularly assessing the trigger function.
Signal Generation and Oscillator Circuit for Testing Oscilloscope
The stepped voltage signal is generated by oscillator IC1a and a digital-to-analog converter (DAC), as illustrated in the diagram. The converter comprises IC2, D1-D4, R3-R6, and R9. T1 functions to buffer the signal, while diode D5 compensates for the forward bias of the base-emitter junction of T1. The introduction of spikes in the signal is attributed to the presence of C4.
Signal Generation for Low-Frequency Testing
The second signal is generated by orchestrating the switching of T2 in synchronization with the 2 kHz signal, while concurrently modifying the collector voltage with the 15 Hz signal produced by oscillator IC1b. To power the circuit, a supply voltage within the range of 9-15 V is required, drawing an approximate current of 50 mA.
Operational Principle of a Digital Storage Oscilloscope
In the operational framework of a digital storage oscilloscope, the input signals stored in analog registers can be read out at a significantly slower rate by the A/D converter. Subsequently, the digital output from the A/D converter is stored in the digital store, facilitating operation at speeds of up to 100 mega samples per second. This delineates the fundamental working principle of a digital storage oscilloscope.
Digital Storage Oscilloscope
The digital storage oscilloscope is an instrument that gives the storage of a digital waveform or the digital copy of the waveform. It allows us to store the signal or the waveform in the digital format, and in the digital memory also it allows us to do the digital signal processing techniques over that signal. The maximum frequency measured on the digital signal oscilloscope depends upon two things they are: sampling rate of the scope and the nature of the converter. The traces in DSO are bright, highly defined, and displayed within seconds.