COMPUTER SCIENCE AND ENGINEERING
DIGITAL LOGIC
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1 second
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3 seconds
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75%
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25%
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Detailed explanation-1: -Period = 1/Frequency (2) Period= T on +T off (3) Duty Cycle= T on / (T on +T off ) * 100 (percentage) (4)
Detailed explanation-2: -25 percent is the duty cycle. Explanation: The ratio of pulse width to pulse period is known as the duty cycle.
Detailed explanation-3: -Duty Factor is calculated via the following equation-DF (%) = (PD ( s) / PRP ( s)) x 100 In these examples you are given the PRP so you need to determine the pulse duration.
Detailed explanation-4: -An approximately 50% duty cycle is achieved by modifying the control voltage to 1/2 the supply voltage. This allows the periods of low and high states to become equal. The 10 kOhms resistor (Rctl) from the control pin of the 555 to ground modifies the reference voltages of the two comparators inside the timer.