Higher Order Filters

jojo June 13, 2011 No Comments
Higher Order Filters From the discussion made so far on the filters, it may be concluded that in the stopband the gain of the filter changes at the rate of 20 db/decade for first-order filters and 40 db/decade for...
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Butterworth Filter

jojo October 7, 2009 No Comments
In many low-pass filter applications it is necessary that the closed-loop gain is as close to unity as possible within the passband. The Butterworth filter is best suited for such applications. This filter is also called a maximally flat...
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Classification of Active Filters

jojo October 7, 2009 No Comments
The most widely used active filters are (i)                 low-pass (ii)                 high-pass (iii)                band-pass (iv)               band-stop or band reject (also called the band-elimination or notch) and (v)                 all-pass filters. All of these filters use op-amps as the active elements and...
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Active and Passive filters

jojo October 7, 2009 No Comments
Active and Passive filters – A Comparison: The simplest approach to building a filter is with passive components (resistors, capacitors, and inductors). In the R-F range it works quite well but with the lower frequencies, inductors create problems. AF...
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Filter Circuits – Active Filters

jojo May 5, 2014 3 Comments
Introduction to Filters An electric filter is a network designed to attenuate certain frequencies but pass others without attenuation. A filter circuit, therefore, possesses at least one pass band — a band of frequencies in which the output is...
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UPS-Uninterruptable Power Supplies

jojo January 17, 2011 22 Comments
Most of us take the mains ac supply for granted and use it almost casually without giving the slightest thought to its inherent shortcomings and the danger posed to sophisticated and sensitive electronic instruments/equipments. For ordinary household appliances such...
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CVT-Constant Voltage Transformer

jojo November 13, 2013 7 Comments
With the popularisation of PCs, the constant voltage transformers (CVTs) have also become equally popular. The CVT is simply a magnetic transformer of a special construction that has a capacitor connected across the secondary winding of the transformer. In an...
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Switching Regulator using LM1758 A

jojo October 5, 2009 No Comments
The National Semiconductor LM 1578 A is a switching regulator which can easily be set up for such dc-to-dc voltage .conversion circuits as the buck, boost, and inverting configurations. The LM 1578 A features a unique comparator input stage...
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Switching Regulators Using LM 2575 and LM 2577

jojo October 5, 2009 No Comments
Switching Regulators Using LM 2575 and LM 2577 Switching regu­lators are available is different circuit configurations in­cluding the flyback, feed-forward, push-pull, and non-iso­lated single-ended or single-polarity types. Also, the switching regulators can operate in any of three modes –...
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Switching Voltage Regulators

jojo July 3, 2014 No Comments
Switching Voltage Regulators All of the voltage regulators we have discussed so far are series regulators, also sometimes called the linear regulators because the pass transistor used in such a regulator operates in the active region. Series regulators are...
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Dual Voltage Supplies

jojo July 8, 2014 4 Comments
Dual Power Supply using LM 320 and LM 340 Bipolar or dual voltage supplies can be easily designed with the help of two 3-terminal regulators. This is shown in the figure above using the IC’s LM320 and LM 340....
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IC 723 Voltage Regulators

jojo July 7, 2014 10 Comments
We have already explained in detail about the basics of regulated power supply, voltage regulators and IC voltage regulators. Let us take a look at one of the most popular IC voltage regulators, the 723 Voltage Regulator IC. The functional...
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LM340 Series Voltage Regulators

jojo July 7, 2014 No Comments
Three terminal voltage regulators This series is typical of the three-terminal voltage regulators. The block diagram is shown in figure. The built-in reference voltage VREF drives the non-inverting input of an op-amp. The operational amplifier consists of several stages...
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Adjustable Voltage Regulators

jojo July 3, 2014 8 Comments
Adjustable Voltage Regulators Some­times variable voltage is required and under such a situation adjustable voltage regulator is used. A number of IC regulators, like LM 317, LM 338, and LM 350, are adjustable regulators. They have maximum load currents...
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Fixed Positive Voltage Regulators

jojo October 4, 2009 2 Comments
5Volts to 24volts Voltage Regulators using 78XX series IC 15 volts Power Supply The series 7800 regulators provide eight voltage options, ranging from 5 to 24 V. These ICs are designed as fixed voltage regulators and with adequate heat...
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IC Voltage Regulators

jojo July 7, 2014 6 Comments
A voltage regulator is one of the most widely used electronic circuitry in any device. A regulated voltage (without fluctuations & noise levels) is very important for the smooth functioning of many digital electronic devices. A common case is...
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Controlled Transistor Series Regulator

john October 1, 2009 1 Comment
Controlled Transistor Series Regulator A controlled transistor series regula­tor is shown in the figure. The circuit is quite similar to that of a simple transistor series voltage regulator except that an additional transistor Q2 is inserted in the circuit....
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Zener Controlled Transistor Voltage Regulators

john July 2, 2014 10 Comments
The efficiency of Zener regulated power supply becomes very low when the load current is high. Under such conditions a Zener controlled transistor is always used for maintaining output voltage constant. Basically there are two types of Zener controlled...
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Discrete Transistor Voltage Regulators

john July 2, 2014 No Comments
Basically there are two types of transistor voltage regulators. They are (i) Series Voltage Regulators and (ii) Shunt Voltage Regulators. Each type of circuit can provide an output dc voltage that is regulated or maintained at a predetermined value...
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Voltage Regulators

john July 2, 2014 5 Comments
A voltage regulator is a voltage stabilizer that is designed to automatically stabilize a constant voltage level. A voltage regulator circuit is also used to change or stabilize the voltage level according to the necessity of the circuit. Thus,...
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Regulated Power Supply

john June 23, 2014 14 Comments
INTRODUCTION Almost all basic household electronic circuits need an unregulated AC to be converted to constant DC, in order to operate the electronic device. All devices will have a certain power supply limit and the electronic circuits inside these...
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Basic Controls of a CRO

jojo September 24, 2009 6 Comments
Number of controls are required to be provided on a panel of CRO to facilitate its proper functioning. Intensity control is provided for adjustment of brightness of the spot on the screen. It is accomplished by varying the voltage...
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CRT-Cathode Ray Tube

jojo September 24, 2009 3 Comments
Cathode ray tube essentially consists of an electron gun for producing a stream of electrons, focusing and accelerating anodes for producing a narrow and sharply focused electron beam, horizontal and vertical deflection plates for controlling the beam path and...
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