Is there any limit to the number of times that a 74123 can be retriggered? yes n

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Question
Is there any limit to the number of times that a 74123 can be retriggered?
Options
A. yes
B. no

Correct Answer

no

Multivibrators and 555 Timer problems

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3. To obtain a 50% duty cycle in an astable 555 timer circuit:
Options
A. t_LO = t_HI
B. R_A = R_B and short R_B with a diode during the capacitor charging cycle
C. capacitor voltage must rise above 1/3 V_CC
D. t_LO = t_HI, R_A = R_B, and short R_B with a diode during the capacitor charging cycle

5. In a typical IC monostable multivibrator circuit, at the falling edge of the trigger input, the output switches HIGH for a period of time determined by the ________.
Options
A. value of the RC timing components
B. amplitude of the input trigger
C. frequency of the input trigger
D. magnitude of the dc supply voltage

6. Determine t_HI and t_LO for the circuit given below.
Options
A. t_HI = 7.95 µs, t_LO = 6.24 µs
B. t_HI = 6.24 µs, t_LO = 7.95 µs
C. t_HI = 3.97 µs, t_LO = 3.21 µs
D. t_HI = 3.21 µs, t_LO = 3.97 µs

9. What is the difference between an astable multivibrator and a monostable multivibrator?
Options
A. The astable is free running.
B. The astable needs to be clocked.
C. The monostable is free running.
D. none of the above

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