An operational amplifier exhibits a 5 V/μS slew rate. The largest sinusoidal output voltage achievable at 1 MHZ is [Hint: Slew rate is the max rate of change of output voltage, measured in V/μS.]
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Answer: D. 5/2 volts
Explanation
Maximum sinusoidal output voltage amplitude without distortion is limited by slew rate limits. Slew rate divided by two pi times frequency yields the peak output voltage amplitude. Dividing five volts per microhertz by two pi times one megahertz gives five over two volts. Slew rate measures the maximum rate of change of output voltage per unit time in op-amps. Exceeding the slew rate causes severe triangular distortion in high frequency sinusoidal signals. Units of volts per microsecond and megahertz cancel out to yield peak voltage in volts.
Audio and signal generator design requires checking operational amplifier slew rate specifications. High frequency square waves demand very fast slew rates to maintain sharp rising edge transitions. Signal distortion in function generators often stems from hitting operational amplifier slew limits. Option A is wrong because ten volts exceeds the maximum slew rate limit at one megahertz. Option B is incorrect because five volts is too high and would cause severe waveform clipping. Option C is wrong because it omits the crucial two pi factor from the sinusoidal rate equation.
- Subject
- Engineering
- Category
- Electrical Engineering
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- —
- Difficulty
- medium
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