Problems that are easy to be ignored in oscilloscope measurements

Oscilloscopes provide great convenience to engineers when performing high-precision measurements. With some simple techniques, it is easy to measure the desired results. However, can you guarantee that the data is truly accurate? Have you ever overlooked the following situations? Although they are very basic.

1. Ignoring the bandwidth of the oscilloscope and probe.
We all know that the bandwidth of the oscilloscope and probe should be 3 to 5 times the highest frequency of the measured signal, so that the frequency response and fast rising edge can be measured more accurately. The oscilloscope and probe must have sufficient bandwidth to make the measured data more accurate, so the wider the bandwidth of the oscilloscope and probe, the better. Did you ignore this?

2. Ignoring the compatibility of oscilloscopes and probes
Have you ever used an oscilloscope produced by Company A and a probe produced by Company B to measure data? Before you mix and match, have you learned about the compatibility of the two oscilloscopes and probes? It is recommended to use oscilloscopes and probes of the same brand to reduce data errors caused by compatibility issues.

3. Ignoring the recalibration of the oscilloscope
Do you use the oscilloscope directly every time you measure without recalibrating it? Jie Chuang reminds you that you should perform manual calibration before starting measurement, or use the oscilloscope's self-calibration function, which can better ensure the accuracy of the data.

4. Ignoring the selection of probes
. Different probes should be selected for different measurements, which will definitely give the best measurement results.

5. Ignoring additional factors in probe grounding
When making high-speed measurements, using a ground clip is equivalent to adding a series inductor to the ground path. The best ground connection method is to use the ground shield inside the probe, which can exclude any series inductance and almost eliminate all oscillations and overshoots. This also increases the accuracy of the data.

6. Ignoring differential measurements
When measuring time difference or transmission delay, make sure you use two probes of the same length. Different cable lengths can cause you trouble. If you want to distinguish measurements in units of 1 ns, the error will be quite large.