Suntan What is a capacitor?
A capacitor is a passive electronic component that store senergy in the form of an electrostatic field. In its simplest form, a capacitor consists of two conducting plates separated by an insulating material called the dielectric. The capacitance is directly proportional to the surface areas of the plates, andis inversely proportional to the separation between the plates. Capacitance also depends on the dielectric constant of the substance separating the plates.
The standard unit of capacitance is the farad, abbreviate dF. This is a large unit; more common units are the microfarad, abbreviated µF (1 µF =10-6F) and the pico farad, abbreviated pF (1 pF = 10-12 F).
Capacitors can be fabricated onto integrated circuit (IC)chips. They are commonly used in conjunction with transistors in dynamic random access memory (DRAM). The capacitors help maintain the contents of memory. Because of their tiny physical size, these components have low capacitance. They must be recharged thousands of times per second or the DRAM will lose its data.
Large capacitors are used in the power supplies of electro nice quipment of all types, including computers and their peripherals. In these systems, the capacitors smooth out the rectified utility AC, providing pure, battery-like DC.
