Final output stage

To properly design the capacitance for the output stage, one should place enough capacitors in parallel so that each capacitor operates at about 70 to 80 percent of its maximum ripple current rating. The sum of the capacitors should equal the final calculated value, but each capacitor should have the value of Ctot/fi, where n is the number of capacitors in parallel. 

The main purpose behind the power switch section is to convert the dc input voltage to a pulsewidth modulated ac voltage. The following stages can use a transformer to step-up or step-down the ac waveform, and finally the output stage converts the ac into the dc output(s). To accomplish the dc-to-ac conversion, the power switch operates only in the saturated and cutoff states. This makes the losses as low as possible. 

Type III industrial systems represent the final ideal stage in which the industrial systems recycle all of the material outputs of production, although still relying on external energy inputs. 

Qn = output flow rate from the final preconcentration stage... 

A photomultiplier (PM) tube is more sensitive than a phototube for the visible and ultraviolet regions. It consists of a photoemissive cathode, which the photon strikes, and a series of electrodes (dynodes), each at a more positive potential (50 to 90 V) than the one before it. When an electron strikes the photo-emissive surface, a primary electron is emitted (this is the photoelectric effect— Albert Einstein received the 1921 Nobel Prize in Physics for its discovery in 1905, not for the special theory of relativity which he also introduced in 1905—see www.lucidcafe.com/lucidcafe/librarv/96mar/einstein.htmD. The primary electron released from the photoemissive surface is accelerated toward the first dynode. The impact of the electron on the dynode surface causes the release of many secondary electrons, which in turn are accelerated to the next electrode where each secondary electron releases more electrons, and so on, up to about 10 stages of amplication. The electrons are finally collected by the anode. The final output of the photomultiplier tube may, in turn, be electronically amplified. 

Output stage The final driving circuit in a piece of electronic equipment. 

In a final stage, the change of the phase difference causes a change of the interference pattern from which, using Fourier analysis, the A(p, can be derived. This has been treated in Sect. 10.2.2 and has consequences for the distance between the output channels only. 

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