Does the 74123 one shot have an internal timing resistor? yes no

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Question
Does the 74123 one shot have an internal timing resistor?
Options
A. yes
B. no

Correct Answer

no

Multivibrators and 555 Timer problems

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1. The monostable multivibrator circuit is not an oscillator because ________.
Options
A. its output switches between two states
B. it requires a trigger to obtain an output signal
C. it requires a sine wave input signal
D. the circuit does not require a dc power supply

2. Triggering a retriggerable one shot during pulse generation will:
Options
A. time out the original pulse
B. extend the pulse to this trigger width
C. have no effect
D. double the original pulse width

5. What is the function of the comparators in the 555 timer circuit?
Options
A. to compare the output voltages to the internal voltage divider
B. to compare the input voltages to the internal voltage divider
C. to compare the output voltages to the external voltage divider
D. to compare the input voltages to the external voltage divider

6. What does the discharge transistor do in the 555 timer circuit?
Options
A. charge the external capacitor to stop the timing
B. charge the external capacitor to start the timing over again
C. discharge the external capacitor to stop the timing
D. discharge the external capacitor to start the timing over again

8. The internal circuitry of the 555 timer consists of ________, an R-S flip-flop, a transistor switch, an output buffer amplifier, and a voltage divider.
Options
A. a comparator
B. a voltage amplifier
C. two comparators
D. a peak detector

10. Design a circuit using a 74121 to convert a 33-kHz, 30% duty cycle waveform to a 33-kHz, 60% duty cycle waveform.
Options
A. R_int = 2 kΩ, C_ext = 0.012 nF
B. R_int = 2 kΩ, C_ext = 0.012 µF
C. R_int = 4 kΩ, C_ext = 0.012 nF
D. R_int = 4 kΩ, C_ext = 0.012 µF

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