Optimum capacitance

Two other useful parameters related to capacitive sparks and dust ignitions are (i) the optimum sparking distance is 10 mm and (ii) the quenching distance is 7 mm. Refer to Sec. 4.1 and Table 5, where MIE is discussed in more detail. 

In one of the most common types of photodiodes used for time-resolved work, the p-i-n photodiode (see Figure 12.24), the depletion layer thickness (i for intrinsic) is fabricated to obtain this optimum performance. Manufacturers usually give full specification sheets detailing, active area, time/frequency response, responsivity amps/watt (AAV) at a given wavelength, dark current, depletion layer capacitance, and bias volts such that with minimal external electronics devices can be made operative. 

If / iCi = R2C2, then there is no phase difference between /,n and Vout- The optimum value of C2 can be determined by trial and error. Taking / i = 100 Mfi and / 2 = 1 Mfl, the typical value of C2 is 10 20 pF. The compensation is never perfect, because there are other stray capacitances in the circuit, which are not compensated by this simple RC network. Nevertheless, a bandwidth of 100 kHz is attainable. 

The tangent of the capacitance phase angle has been shown to be a measure of the completeness of the anneal (2.) Based on this technique, we have data which would predict 30 minutes at 300°C is sufficient to obtain optimum dielectric properties. However, we have found chronogravimetric analysis of polyimide films to be more useful in defining optimum anneal conditions. 

In an electrical system, if the power factor is 0.80, 80% of the apparent power is converted into useful work. Apparent power is what the transformer that serves a home or business has to carry in order for that home or business to function. Active power is the portion of the apparent power that performs useful work and supplies losses in the electrical equipment that are associated with doing the work. Higher power factor leads to more optimum use of electrical current in a facility. Can a power factor reach 100% In theory it can, but in practice it cannot without some form of power factor correction device. The reason why it can approach 100% power factor but not quite reach it is because all electrical circuits have inductance and capacitance, which introduce reactive power requirements. The reactive power is that... 

An electrical measuring instrument contains electrical circuits incorporating capacitance, inductance, and resistance. In the absence of resistance, a circuit tends to oscillate with a definite frequency /when disturbed. For optimum performance an amount of resistance is incorporated that is barely sufficient to damp the oscillations resulting from transient inputs the circuit is then said to be critically damped. For a critically damped circuit it can be shown that the root-mean-square (rms) fluctuations in voltage V and in current /are given by... 

These considerations can be put into quantitative form by analyzing the information content of the measurement. To understand this concept, let us first consider the choice of the optimum time scale for making a measurement. We already know that by using a very fast transient we can minimize the effects of diffusion, so we would first be inclined to use the fastest transients allowed by instrumentation. But if the measurement is conducted on a time scale that is short compared to X, all we can observe is a linear variation of potential with time, which depends on the double-layer capacitance (dtl/dt = We cannot calculate i... 

The best resolution which can be achieved with optimal filtering does not depend on the value of the resistive chain R, but solely on the eletrode capacitance. The optimum resolution is given by... 

The antenna consists of a resonant if circuit with parallel and series capacitors, Cp and Cs, for tuning of the resonance frequency and for matching of the impedance, respectively (Fig. 2.3.5(a)). The impedance is a complex quantity which needs to be adjusted to 50 Q magnitude and 0° phase for optimum transfer of rf power. Depending on the equivalent resistance R, inductance L, and capacitance C of the components of the antenna (Fig. 2.3.5(b)), the quality factor... 

The capacity of the ion-exchange column is important for achieving good recoveries and sensitivity in the analysis of urine samples. Low capacities may result in low recoveries (e.g. 78% recovery for 100 p column) while large capacitic lcL ase the EF value (e.g. F = 21 for 400 p column). 200 p columns give optimum overall performance. 

Optimum device isolation is not only restricted to the deep trench isolation between devices, but also calls for shallow trenches to allow isolation between the base and the subcollector reach-through diffusion. This trench reaches down to the subcollector only. A third trench shape option is that of wide, deep trenches. These would be formed outside of the immediate device areas and serve (after filling with SiO ) as the bed on which to locate the wiring lines which interconnect the different devices and circuits. Locating wires on such SiO2 areas reduces the wiring capacitances significantly. 

The MMW electrical properties of the cavity and the oscillator at resonance are effectively fixed in their manufacture. This treatment addresses the coupling between those two circuit elements to achieve optimal performance. It considers only the circuits at resonance that is, under the working condition of the spectrometer. Recall that the capacitive and inductive reactances in a tuned circuit at resonance cancel each other yielding a purely resistive circuit element. Nonetheless the reactances both still remain and are manifest in the property Q. The treatment will yield the reflection coefficient p of the coupling interface between the cavity and oscillator in terms of their gs and the mutual inductance coupling coefficient M of the impedance transformer that the interface represents. Optimum performance will be when the two circuit elements are critically coupled to each other and that will be shown to occur when p = 0. 

The parallel capacitance calculated from the data of Figure 7.16 is not a pure double-layer capacitance, it is too frequency-dependent. It must be due to redox or sorption processes at the platinum surface, or the fractal surface of black platinum. Under optimum conditions, it is possible to obtain capacitance values of the order of 50 pF/mm at 20 Hz (Schwan, 1963). 

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