In this video Ms. Shristy Khandelwal, asst. professor, B. Tech Dpartment, Electronics and Communication, Biyani Girls College, Jaipur explains about the PLL which is a control system that generates a signal that has a fixed relation to the phase of a reference signal. In other words, PLL is a circuit which generates a frequency and then detects phase difference between input and output frequency according to which it corrects the output frequency, so as to lock or synchronize the frequency of a controlled oscillator. PLL consists of three blocks i.e phase detector, low pass filter, and voltage controlled oscillator.
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In this video Ms. Shristy Khandelwal, asst. professor, Biyani Girls College, explains the purpose of power amplifier which takes a signal from a source device and makes it suitable for driving a loud speaker. Audio power amplifiers are those amplifiers which are designed to drive loud speakers .Power is not really something that can be “amplified”. Voltage and current can be amplified.
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