Potentiometer voltage divider

This circuit gives the user the option to use a DC current or to use a pulsed current as a load (useful for checking load-switching transients of power supplies). The 15 V input signal is dropped to 10 V by a 5 V zener in series. Switch A selects between the simple potentiometer voltage divider circuit (limited to 5 V maximum by the divider resistors)... 

Potentiometer (voltage divider) with sliding contact... 

Helical potentiometer — A metal wire wound around an insulating cylinder used as variable - voltage divider. A helical potentiometer has been used in the first -> po-larograph developed by - Heyrovsky and - Shikata. The helical potentiometer with a sliding contact was invented by - Kohlrausch (in German Kohlrausch Walze). A commercial version is called a Helipot. 

A variable resistor can also be used as a voltage divider. In this case three connections are used. The total voltage is put over the resistive element the required voltage is obtained by adjusting the position of the sliding contact. Variable resistors that are used in this way are also called potentiometers. 

Two resistors with a connection available between them (the white wire) can be called a "potentiometer." (Potential is another word for voltage — see the middle of page 14. The reason for the "meter" in the word is that this is sometimes used to measure voltage, but that will have to be explained in more detail later.) It can be used to divide a large voltage (9.5V in this case) into smaller parts (like 7.3V, etc.). Sometimes it is called a "voltage divider."... 

A second type of voltage divider is shown in Figure 2-2b. This type is called a potentiometer and provides a voltage that is continuously variable from 0.00 V to the full input voltage V g. In most potentiometers, the resistance is linear —that is. the resistance between one end. A, and any point, C, is directly proportional to the length. AC, of that portion of the resistor. Then Rar = kAC, where AC is expressed in convenient units of length and 1 is a proportionality constant. Similarly, R g = kAB. Combining these relationships with Equation 2-10 yields... 

Thick-film resistor pastes are composed of a combination of glass Mt, metal and oxides. Resistor pastes are available in values ranging from 0.2 ohm/sq to 10 M ohm/sq. Firing temperatures 600-850°C. Temperature coefficient of resistance can vary from 40-150 ppm/C. These pastes are used in microcircuits, voltage dividers, resistor networks, chip resistors and potentiometers. 

Assume that the following experiment is performed (Fig. 5.2). A radioactive source of constant intensity is placed at a fixed distance from a gas counter. The high voltage (HV) applied to the counter may be varied with the help of a potentiometer. An appropriate meter measures the charge collected per unit time. If the HV applied to the counter is steadily increased, the charge collected per unit time changes as shown in Fig. 5.3. The curve of Fig. 5.3 is divided into five regions, which are explained as follows. 

A resistor is an electrical component that resists the flow of either direct or alternating current. Resistors are commonly used to protect sensidve components or to control the flow of current in a circuit. Moreover, a resistor can be used to divide or control voltages in a circuit. There are two broad groups of resistors fixed-value resistors and variable resistors. As the name implies, the fixed-value resistor has a fixed value. On die other hand, the variable resistors, sometimes called potentiometers, can be adjusted to a desired value. The variable resistors are used in various drcuits to adjust the current in the circuit. For example, variable resistors are used in light switches that allow you to dim the light. They are also used to adjust the... 

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