It is called a varactor or a varicap diode. Its capacitance varies nonlinearly with the reverse voltage applied to its terminals.
RPS is only the voltage& power controlled device. it can only used for set the input for our wish A device which can change its output according to the voltage supplied to it is called a voltage controlled device.ex. a voltage controlled current source,or a field effect transistor. In a voltage controlled current source the output current changes as the voltage supplied to it changes.
They are frequently used to provide a voltage reference in voltage regulators.
zener diode
When an AM signal is received, the receiver must perform a converse process to get the original signal ( Information Signal ) back . This process is known as detection or demodulation, the simplest process which is used widely in AM radios is the Envelop Detector . Envelop Detector is an electronic circuit which is used to recover ( Demodulate ) the original signal in AM systems, its constructed from just one diode, one capacitor and one resistor . This is essentially just a halfwave rectifier which charges a capacitor to a voltage = the peak voltage of the AM signal . However .. the output of the detector follows the envelop of the modulated signal. On the positive cycles of the input signal, the diode conducts and the capacitor charges up to the peak voltage of the input signal. As the input falls below this peak value, the diode is cut off, because the capacitor voltage is greater than the input signal voltage, thus causing the diode to open. The capacitor now discharges through the resistor at slow rate . The discharge process continues until the nest positive half-cycle. When the input signal becomes greater than the output across the capacitor, the diode conducts again and the process is repeated .
Work in reverse bias.(breakdown at a particular voltage to keep the volt. constant so used as voltage regulator) same as diode when forward biased.
Varactor didoe is used as voltage controlled capacitor.it is generally used in reverse bias condition.
Voltage controlled variable capacitor. Usually used for dynamic tuning of resonant circuits.
The effective resistance of the capacitor reduces the ripple current through the capacitor making it less effective in its function of smoothing the voltage. But if the capacitor filter is fed by a transformer and diodes, the resistance of the transformer exceeds that of the capacitor.
varactor diode is a correct answer
RPS is only the voltage& power controlled device. it can only used for set the input for our wish A device which can change its output according to the voltage supplied to it is called a voltage controlled device.ex. a voltage controlled current source,or a field effect transistor. In a voltage controlled current source the output current changes as the voltage supplied to it changes.
Since a capacitor resists a change in voltage, it is used to provide voltage to the regulator circuit between the point in time where the rectifying diode turns off, and the point in time where it turns back on. It is a low-pass filter.
They are frequently used to provide a voltage reference in voltage regulators.
zener diode
Both a capacitor and battery "store charge". However, in a battery there is a chemical reaction that continues to generate charge. You apply a charge across the "plates" of a capacitor and it will decay over time from leakage or through a discharge resistance to ground in the circuit. You need really large capacitors to store meaningful amounts of charge, to take the place of a battery for example.
to limit the voltage or regulate the same.
The varactor diode is a semiconductor diode but in this kind, the capacitance is supposed to vary according to the applied voltage. It has an exponent factor that bears a negative fraction value.
When an AM signal is received, the receiver must perform a converse process to get the original signal ( Information Signal ) back . This process is known as detection or demodulation, the simplest process which is used widely in AM radios is the Envelop Detector . Envelop Detector is an electronic circuit which is used to recover ( Demodulate ) the original signal in AM systems, its constructed from just one diode, one capacitor and one resistor . This is essentially just a halfwave rectifier which charges a capacitor to a voltage = the peak voltage of the AM signal . However .. the output of the detector follows the envelop of the modulated signal. On the positive cycles of the input signal, the diode conducts and the capacitor charges up to the peak voltage of the input signal. As the input falls below this peak value, the diode is cut off, because the capacitor voltage is greater than the input signal voltage, thus causing the diode to open. The capacitor now discharges through the resistor at slow rate . The discharge process continues until the nest positive half-cycle. When the input signal becomes greater than the output across the capacitor, the diode conducts again and the process is repeated .