Voltage divider distribution

In bilayer LEDs the field distribution within the device can be modified and the transport of the carriers can be controlled so that, in principle, higher efficiencies can be achieved. On considering the influence of the field modification, one has to bear in mind that the overall field drop over the whole device is given by the effective voltage divided by the device thickness. If therefore a hole-blocking layer (electron transporting layer) is introduced to a hole-dominated device, then the electron injection and hence the efficiency of the device can be improved due to the electric field enhancement at the interface to the electron-injection contact, but only at expense of the field drop at the interface to the hole injection contact This disadvantage can be partly overcome, if three layer- instead of two layer devices are used, so that ohmic contacts are formed at the interfaces [112]. 

To illustrate the basic operation of the Monte Carlo and Worst Case analyses, we will simulate a voltage divider. Create a voltage divider using 5% resistors with Gaussian distributions as follows. 

B.2.a. Voltage Divider Gain Analysis with Uniform Tolerance Distribution... 

EXERCISE 9-2 What percentage of the voltage divider circuits will have a gain of 0.49 or greater if 10% resistors with a Gaussian distribution are used ... 

The Performance Analysis can be used in conjunction with the Monte Carlo analysis to view the distribution of a parameter as a function of device tolerances. For this example, we will display how the spread of the gain V(Vo)/V(Vl) varies with resistor tolerances. We will use the voltage divider of the previous section and 5% resistors with a uniform distribution ... 

To apply the electric field to the dynodes, a power supply provides a voltage adequate for all the dynodes. A voltage divider, usually an integral part of the preamplifier, distributes the voltage to the individual dynodes. When reference is made to phototube voltage, one means the total voltage applied. For example, if 1100 V are applied to a phototube with 10 dynodes, the voltage between any two dynodes is 100 V. 

For installations with several storage tanks and a protection current of several tens of an mA, uniform protection current distribution should be the goal, so that the current injection occurs via a number of anodes distributed over the site or via a more distant anode bed. Dividing up the protection current over several anodes avoids large local anodic voltage cones and therefore effects on neighboring installations. 

The equivalent circuit of an electrochemical cell is shown in Fig. 5.6. It can be represented by a capacitive divider consisting of Cw and CAux connected in series. Figure out how the voltage V and charge Q are distributed across this divider when the resistances are (a) finite (b) infinite. 

Here E is the applied field driving the electro-osmosis and is equal to the voltage V divided by /, the thickness of the porous diaphragm, assuming a uniform distribution of field other terms have been defined in coimec-tion with Eq. (2). 

The parameters involved in the electrospinning processes that affect the nanofiber geometry and structure can be divided into two groups (i) System parameters such as polymer molecular weight, molecular weight distribution, polymer architecture (branched, linear), concentration of the polymer solution and its properties, including viscosity, electrical conductivity, and surface tension and (ii) Process parameters such as applied electric voltage, polymer flow rate, distance between the needle tip and the collector, ambient parameters such as temperature, humidity, and air velocity in the chamber, and motion of the collector (Frenot and Chronakis 2003). 

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