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Capacitance (a type of electronic components) generally refers to a capacitor Capacitor, typically referred to its ability to hold a charge capacitanc
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capacitance
Capacitance (a type of electronic components) generally refers to a capacitor
Capacitor, typically referred to its ability to hold a charge capacitance, denoted by the letter C. Definition 1: Capacitors, by definition, is 'loaded container electricity', it is a device receiving the charge. English name: capacitor. Capacitor is one of a large number of electronic components used in electronic equipment, it is widely used in the circuit compartment straight cross-connection, coupling, bypass, filtering, tuning circuits, energy conversion and control. Definition 2: Capacitors, between any two conductors insulated from each other and closely spaced (including lead) constitute a capacitor.
The capacitance of the capacitor is different. Capacitance basic physical quantities, the symbol C, the unit is F (farad).
General formula C = Q / U parallel plate capacitor special formula: electric field strength between the plates E = U / d, the capacitor capacitance of the formula C = εS / 4πkd
With the ever-changing electronic information technology, upgrading the speed of digital electronic products faster and faster, with flat panel TV (LCD and PDP), notebook computers, digital cameras and other products of consumer electronics production and sales continued to grow, driven by capacitor industry growth.
Chinese name: Capacitors
English name: capacitor
Capacitor Application: hold a charge device
Capacitor determine the formula: C = εS / 4πkd
Symbol: C
Capacity said: direct standard method
Capacitance defined formula: C = Q / U
Definition of the capacitor: is sandwiched between two metal electrodes with an insulating dielectric material. When a voltage is applied between two metal electrodes, the upper electrode will be stored charge, so the capacitor is the storage element. Any two closely spaced from each other and insulated conductors to form a capacitor. Parallel plate capacitor formed by the capacitor plates and the dielectric composition [1].
Features:
1. It has a charge and discharge characteristics and prevent DC current through, allowing the ability to communicate current through.
2. In the process of charging and discharging, the charge accumulation process have bipolar plate, that the process of establishing voltage, the voltage on the capacitor can not change suddenly.
The charging capacitor: two plates are dissimilar with the same amount of charge of each plate with absolute power band called capacitors charge.
Capacitor discharge: positive and negative charges across the capacitor via conductors and. During discharge of currents on a short lead.
3. The capacitor capacitance and frequency is inversely proportional between capacity. That must contact of frequency, capacity, size of the signal analysis capacitance size.
The role of the capacitor
In the DC circuit, a capacitor is the equivalent of disconnection. A capacitor is a device capable of storing electric charge, it is also one of the most commonly used electronic components.
We were talking about from the structure of the capacitor. The simplest is a capacitor plate and intermediate the ends of the insulating dielectric (including air) configuration. When energized, the charged plate, forming a voltage (potential difference), but due to the intermediate insulation materials, so the entire capacitor is not electrically conductive. However, this situation is in the capacitor does not exceed the critical voltage (breakdown voltage) of preconditions. We know that any substance is relatively insulated, when the voltage across the material increased to a certain extent, the substance can be conductive, we call this voltage is called breakdown voltage. Capacitance is no exception, after the capacitor is the breakdown, the insulator is not. However, at the secondary level, this voltage is not seen in the circuit, so are operating below the breakdown voltage, can be used as an insulator to see.
However, in AC circuits, because the direction of the current over time as a function of certain changes. The process of charging and discharging the capacitor is a time, and this time, the change in the electric field between the plates is formed, and this field is also a function of change over time. In fact, the current is in the form of an electric field between the capacitor through.
Capacitor effects:
● Coupling: The coupling capacitance in the circuit called coupling capacitance, the extensive use of such a capacitor circuit in RC coupled amplifier and other capacitive coupling circuit, blocking flow from the exchange effect.
● Filtering: used in the filter circuit called a capacitor filter capacitor, using this power supply filter capacitor circuit and a variety of filter circuit, the filter capacitor certain signal band is removed from the total signal.
● decoupling: decoupling circuits used in capacitors called decoupling capacitors, the use of such capacitor circuit in a multi-stage amplifier circuit DC voltage supply, the decoupling capacitors to eliminate harmful low-cross-linked between each amplifier.
● High-frequency vibration absorption: The high-frequency vibration absorption circuit capacitors called high-frequency vibration absorption capacitors in the audio negative feedback amplifier, in order to eliminate high-frequency self-excited oscillation may occur, with this capacitor circuit to eliminate a high frequency amplifier howling may occur [2].
● Resonance: used in LC resonant circuit capacitor called resonant capacitor, LC parallel and series resonant circuits are required this capacitance circuit.
● Bypass: The bypass circuit capacitor called bypass capacitor, the circuit if the signal of a frequency band needs to be removed from the signal, you can use the bypass capacitor circuits, remove the signal according to the different frequencies, with full frequency domain (All AC signal) bypass capacitor circuits and high-frequency bypass capacitor circuit [2].
● neutralization: use in capacitors and circuit called in and capacitors. In the high-frequency and intermediate frequency amplifier radio, TV tuner amplifier, using this medium and capacitive circuits to eliminate self-excitation.
● Timing: The timing circuit capacitor called the timing capacitor. Use in through capacitor charging, discharging time control circuit timing capacitor circuit, a control time constant of the size of the effect from the capacitor.
● Integration: With the integration circuit called a capacitor integrating capacitor. In a potential field scanning sync separator circuit, with this integration capacitor circuit, can be removed and vertical sync signals from the composite sync signal field.
● Differential: Using the differential circuit called differential capacitance of the capacitor. In the flip-flop circuit in order to obtain the steeple trigger signal, using this differential capacitance circuits to (mainly rectangular pulse) signal obtained from a variety of spiers pulse trigger signal.
● Compensation: The compensation circuit called a capacitor compensation capacitor, the deck bass compensation circuit, the use of such low-frequency compensation capacitor circuit, in order to enhance the playback signal from the low-frequency signal, in addition, there are high frequency compensation capacitor circuit [2].
● bootstrap: The bootstrap circuit capacitor called bootstrap capacitor, commonly OTL power amplifier output stage circuit using this bootstrap capacitor circuit, by way of a small amount of positive feedback to enhance the signal amplitude of the positive half cycle [2] ???
● divide: the divider circuit called a capacitor divider capacitor in speaker speaker crossover circuit using capacitive divider circuit, so that work in the high-frequency tweeter, mid-range speakers in the band, low frequency Work speaker at low frequency.
● Load Capacitance: refers to quartz crystal resonators together to determine the resonant frequency of the effective external load capacitance. Commonly used standard load capacitance values ??are 16pF, 20pF, 30pF, 50pF and 100pF. Load capacitance can be appropriately adjusted according to the specific circumstances, generally by adjusting the operating frequency of the resonator is adjusted to the nominal value.
