Transistor Series Voltage Regulator Pdf

Linear regulator

Some of the variable regulators are available in packages with more than three pins, including dual in-line packages. As a result the conduction level of the transistor will increase leading to decrease in the collector-emitter resistance. The ratio of resistances determines the output voltage using the same feedback mechanisms described earlier. The resistance of the regulator varies in accordance with the load resulting in a constant voltage output.

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This article needs additional citations for verification. The emitter follower voltage regulator is, therefore, much more efficient than a simple Zener regulator.

This will lead to increase m the collector-emitter resistance of the transistor causing an increase in collector to emitter voltage and as a result the output voltage will be reduced. The current through the shunt regulator is diverted away from the load and flows uselessly to ground, making this form usually less efficient than the series regulator. Series Regulator - Zener diode.

Potentiometer digital Variable capacitor Varicap. Thus output voltage remains almost constant.

Under such conditions a Zener controlled transistor is always used for maintaining output voltage constant. Linear regulators can be constructed using discrete components but are usually encountered in integrated circuit forms. This is generally limited by either power dissipation capability, or by the current carrying capability of the output transistor. Simple shunt voltage regulator.

This decrease in output voltage is enough to compensate the initial increase in output voltage. All linear regulators require an input voltage at least some minimum amount higher than the desired output voltage. Because a linear voltage regulator is a common element of many devices, integrated circuit regulators are very common. By contrast, a switching regulator uses an active device that switches on and off to maintain an average value of output.

Transistor series voltage regulator pdf

When the output regulated voltage must be higher than the available input voltage, no linear regulator will work not even a Low dropout regulator. Some regulators require a minimum load.

Some have selectable current limiting as well. Operation i Let the supply or input voltage increase which will cause the output voltage V out to increase. The power dissipated by the regulating device is equal to the power supply output current times the voltage drop in the regulating device. They offer the capability to adjust the output voltage by using external resistors of specific values.

Transistor Series Voltage Regulator

Disadvantages

Reverse happens should the load resist- ance increase. From Wikipedia, the free encyclopedia. Reverse happens should the supply voltage decrease. It may be made step adjustable by switching in different Zeners.

Often, the last two digits of the device number are the output voltage e. This section needs expansion. This form is very common for voltage reference circuits.

The circuit is readily made adjustable by adding a potentiometer across the Zener, moving the transistor base connection from the top of the Zener to the pot wiper. Thus output voltage will remain constant. Linear regulators may also be made up of assemblies of discrete solid-state or vacuum tube components. This circuit is also called an emitter follower voltage regulator because transistor Q is connected in emitter follower configuration. In these cases, the linear regulator may dissipate less power than a switcher.

The transistor or other device is used as one half of a potential divider to establish the regulated output voltage. Here, smart pdf tools pro 2.2 crack the transistor Q is termed a series-pass transistor.

Transistor series voltage regulator pdf

Because of above limitations application of this regulator is limited to low output voltages. Basically there are two types of Zener controlled transistor voltage regulators. The Zener regulator resistor R and Zener diode form a simple Zener regulator has to supply only the base current of the transistor. This can be resolved by incorporating negative feedback circuitry into it.

Transistor Series Voltage RegulatorTransistor Series Voltage Regulator - Electronics Post

An adjustable regulator generates a fixed low nominal voltage between its output and its adjust terminal equivalent to the ground terminal in a fixed regulator. That minimum amount is called the dropout voltage. Remember me on this computer. Sometimes external protection is used, such as crowbar protection.

Similar explanation can be given for decrease in supply voltage. Simple series voltage regulator. Although this circuit has good regulation, it is still sensitive to the load and supply variation.

Thus for heavy load currents pass transistor has to dissipate a lot of power and, therefore, becoming hot. Zener Controlled Transistor Voltage Regulator.