Why is it important to use an oscilloscope with more bandwidth than my device under test?

Why is it important to use an oscilloscope with more bandwidth than my device under test?

Without adequate bandwidth, your oscilloscope will not be able to resolve high-frequency changes. To calculate the oscilloscope bandwidth needed for your application, simply multiply the highest-frequency component of the signals you will be working with by a factor of five. For example, if your bus frequency is in the 800 MHz range, you may need an instrument with 4 GHz bandwidth or higher. This “5 times rule” will give you less than ±2% error in your measurements – typically sufficient for today’s applications.

Learn how bandwidth is defined for an oscilloscope »

The XYZ's of Oscilloscopes »