What does the discharge transistor do in the 555 timer circuit? charge the exter

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Question
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

Correct Answer

discharge the external capacitor to start the timing over again

Multivibrators and 555 Timer problems

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2. 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

3. 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

7. 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

9. 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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