A pulse-width modulator in a switching power...

Question 1 / 27070t66H6YdSEQcSwlRpzVeo

Question 1 of 27070t66H6YdSEQcSwlRpzVeo

A pulse-width modulator in a switching power supply is used to:

Question 1 of 27070

A pulse-width modulator in a switching power supply is used to:

🔍 Key Concepts

• Pulse-width modulation (PWM) and how it controls average power or voltage to a load • Difference between frequency of switching and duty cycle of the switch • Roles of other blocks in a switching regulator: reference source and error amplifier/comparator

💭 Think About

• When a switch is turning fully on and fully off, what aspect of its operation actually changes the average output voltage seen by the load? • If the switching frequency stayed the same but the ratio of ON time to OFF time changed, what would happen to the output voltage? • Which circuit block in a regulator normally provides a stable reference and which block compares output to that reference?

✅ Before You Answer

• Be clear on the definition of duty cycle (ON time / total period) and how it affects average output voltage. • Separate in your mind: which function belongs to a PWM circuit and which belong to a reference and error amplifier. • Ask: does PWM usually vary frequency or pulse width (duty cycle) to regulate output in standard switch-mode power supplies?

Question 1 of 27070

A pulse-width modulator in a switching power supply is used to:

Provide the reference voltage for the regulator.

Vary the frequency of the switching regulator to control the output voltage.

Vary the duty cycle of the regulator switch to control the output voltage.

Compare the reference voltage with the output voltage sample and produce an error voltage.

Question 1 / 27070t66H6YdSEQcSwlRpzVeo

Question 1 of 27070t66H6YdSEQcSwlRpzVeo

A pulse-width modulator in a switching power supply is used to:

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Question 1 of 27070

A pulse-width modulator in a switching power supply is used to: