Suntan Blog

Large capacitors are connected to the amplifier much the same way a battery is. This means that the capacitor's positive terminal is connected to the amplifier's positive terminal (which also means that it's connected to the battery's positive terminal). The same is true of the capacitor's negative terminal (the cap's negative terminal is connected to chassis ground with the amplifier's negative ground terminal). Like this...

Large capacitors are used as a sort of electrical shock absorber. As voltage starts to rise, the capacitor will absorb energy which will tend to keep the voltage from rising as quickly as it otherwise would. If the voltage starts to fall, the capacitor's stored energy will flow out of the capacitor to try to keep the voltage up. A capacitor's ability to absorb/release energy from/to external circuits depends on the capacitor's specs (capacitance, ESR, ESL...), the output impedance of the power source (alternator and power wire in this case) and the circuit's input impedance (into the amplifier's power supply).

Suntan is a tinfoil capacitor of the highest class. Solid tinfoil, together with high grade polypropylene as dielectric, are used in its manufacture. This massive tin layer improves the sound properties in unexpected ways: Because of the great weight of the tinfoil and the resulting mass inertia, oscillation of the foil and the accompanying micro phonic effect are effectively prevented.

No matter where you use the Suntan Supreme--as a coupling capacitor in your CD player or amplifier, or in the crossover of your speakers--you always get the same surprising and impressive performance. This capacitor mobilizes such unbelievable reserves in your sound system that it is really justified to speak of a new dimension of music reproduction. Furthermore, the effect is not only achieved with very expensive high-end components. It delivers a significant enhancement in more price-conscious configurations, making it a very worthwhile upgrade.

Capacitance value measured at 1 MHz will be within tolerance limits.
Capacitors will withstand two times the rated voltage for one to five seconds without arcing. The charging current is limited to 50 mA.
Insulation resistance will be greater than 100,000 megaohms when measured at 100V DC.
D.F. as per graph below.

(for C < 80 pf and C > 1000 pf )
Operating temperature (-) 55° C to (+) 125° C.

A capacitor (formerly known as condenser) is a passive electronic component consisting of a pair of conductors separated by a dielectric (insulator). When there is a potential difference (voltage) across the conductors a static electric field develops in the dielectric that stores energy and produces a mechanical force between the conductors. An ideal capacitor is characterized by a single constant value, capacitance,measured in farads. This is the ratio of the electric charge on each conductor to the potential difference between them.

Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies and for many other purposes.

Most types of capacitor include a dielectric spacer, which increases their capacitance. These dielectrics are most often insulators. However, low capacitance devices are available with a vacuum between their plates, which allows extremely high voltage operation and low losses. Variable capacitors with their plates open to the atmosphere were commonly used in radio tuning circuits. Later designs use polymer foil dielectric between the moving and stationary plates, with no significant air space between them.

In order to maximise the charge that a capacitor can hold, the dielectric material needs to have as high a permittivity as possible, while also having as high a breakdown voltage as possible.

The capacitor (C) in the circuit diagram is being charged from a supply voltage (Vs) with the current passing through a resistor (R). The voltage across the capacitor (Vc) is initially zero but it increases as the capacitor charges. The capacitor is fully charged when Vc = Vs. The charging current (I) is determined by the voltage across the resistor (Vs - Vc):

Charging current, I = (Vs - Vc) / R   (note that Vc is increasing)

At first Vc = 0V so the initial current, Io = Vs / R

Vc increases as soon as charge (Q) starts to build up (Vc = Q/C), this reduces the voltage across the resistor and therefore reduces the charging current. This means that the rate of charging becomes progressively slower.

The capacitance of certain capacitors decreases as the component ages. In ceramic capacitors, this is caused by degradation of the dielectric. The type of dielectric and the ambient operating and storage temperatures are the most significant aging factors, while the operating voltage has a smaller effect. The aging process may be reversed by heating the component above the Curie point. Aging is fastest near the beginning of life of the component, and the device stabilizes over time. Electrolytic capacitors age as the electrolyte evaporates. In contrast with ceramic capacitors, this occurs towards the end of life of the component.

Capacitors, especially ceramic capacitors, and older designs such as paper capacitors, can absorb sound waves resulting in a microphonic effect. Vibration moves the plates, causing the capacitance to vary, in turn inducing AC current. Some dielectrics also generate piezoelectricity. The resulting interference is especially problematic in audio applications, potentially causing feedback or unintended recording. In the reverse microphonic effect, the varying electric field between the capacitor plates exerts a physical force, moving them as a speaker. This can generate audible sound, but drains energy and stresses the dielectric and the electrolyte, if any.

The Decoupling capacitor is used to decouple the IC from the power source. The By-Pass capacitor reduces the trace length from the power source to a trace length from the IC to the decoupling capacitor ~ a reduction from many inches to less then an inch. A reduction of 20nH an inch in trace inductance is achieved by introducing a decoupling capacitor in between the IC and its power source. Assuming the power source is a regulator 12 inches away, and the by-pass capacitor is placed within an inch of the IC, the trace inductance is reduced from 240nH to 20nH.

Electronic capacitors are one of the most widely used electronic components. These electronic capacitors only allow alternating or changing signals to pass through them, and as a result they find applications in many different areas of electronic circuit design. Suntan supply a wide variety of types of capacitor including electrolytic, ceramic, tantalum, plastic, sliver mica, and many more. Each capacitor type is introduced in www.suntan.com.hk.

The choice of the correct capacitor type can have a major impact on any circuit. The differences between the different types of capacitor can mean that the circuit may not work correctly if the correct type of capacitor is not used.

Although the construction techniques and materials used to manufacture multilayer ceramic and tantalum capacitors are completely different, the basic applications still remain the same. Capacitors in the 0.1 - 22µF range are used mainly for digital circuit decoupling and filtering. Acting as local supplies of charge, capacitors assist power supplies in remaining at a constant DC voltage despite the continuous switching of digital signal circuitry. Capacitors also function as simple, single pole filters and can be used in conjunction with other devices (resistors and inductors) to create higher order filter circuits.

As much as tantalums and ceramics are both capacitors, they do have many different properties. The case sizes and capacitance values available will first be studied. The impedance curves, the parasitic inductance (ESL) and equivalent series resistance (ESR) for each of the technologies will also be outlined. Then the electrical performance under a variety of conditions, such as temperature and DC bias, will be examined.