Topic: Electronic Measurements and Instrumentation
A pulse signal having 100 kHz frequency and 70 nsec rise time is to be measured on an oscilloscope. The minimum required bandwidth of the oscilloscope is,
- A. 500 kHz
- B. 14.3 MHz
- C. 5 MHz
- D. 200 kHz
Answer: C. 5 MHz
Explanation: The relationship between rise time ($t_{r}$) and bandwidth ($B.W.$) is given by $t_{r} = \frac{0.35}{B.W.}$.
Therefore, $B.W. = \frac{0.35}{t_{r}} = \frac{0.35}{70 \times 10^{-9}} = 5 \times 10^{6}\text{ Hz} = 5\text{ MHz}$.