555 TIMER AND ITS PWM APPLICATION

Which of the following is NOT a mode of operation of 555 timer IC?

• a) Astable
• b) Monostable
• c) Bistable
• d) Triable

What is the main application of 555 timer IC in PWM circuits?

• a) voltage regulation
• b) current regulation
• c) frequency modulation
• d) duty cycle modulation

In 555 timer IC astable mode, what is the time period of the output waveform dependent on?

• a) The resistors R1 and R2
• b) The capacitor C
• c) The voltage across the capacitor
• d) Both resistors R1 and R2 and capacitor C

What is the maximum duty cycle that can be obtained from a 555 timer IC in astable mode?

• a) 50%
• b) 75%
• c) 90%
• d) 100%

What is the function of the control voltage pin (pin 5) in 555 timer IC?

• a) to adjust the output frequency
• b) to adjust the duty cycle of the output waveform
• c) to adjust the voltage threshold for triggering
• d) to adjust the voltage level at which the output switches state

In 555 timer IC monostable mode, how is the pulse width of the output waveform determined?

• a) by the resistors R1 and R2
• b) by the capacitor C
• c) by the voltage across the capacitor
• d) by the value of the timing resistor and capacitor

What is the output waveform of a 555 timer IC in bistable mode?

• a) square wave
• b) triangular wave
• c) sine wave
• d) there is no output waveform in bistable mode

What is the function of the discharge pin (pin 7) in 555 timer IC?

• a) to discharge the timing capacitor
• b) to discharge the external capacitor in PWM circuits
• c) to discharge the internal power supply
• d) to discharge the external power supply