band pass presentation

8/3/2019 Band Pass Presentation

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Active Band-pass

Filters

Presented By:Talal Ahmed

Mohammed Al-Aqil

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Outline

Introduction

What is band-pass filter ?

How to design a band-pass filter ?

An example of designing a band-pass filter

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Introduction

An active filter is a type of analog electronic filter,

distinguished by the use of one or more active

components.

Active filters have two main advantages over passivefilters:

Inductors can be avoided.

The shape of the response, and the tuned frequency can

often be set easily by varying resistors.

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Introduction (Contin

ued)

Types of active filters:

High-pass filters

Low-pass filters

Band-pass filters

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Low pass active filter

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attenuation of frequencies above their cut-off points.


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High pass active filter

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attenuation of frequencies below their cut-off points.


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Band pass active filter

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There are applications where a particular band, or spread, or

frequencies need to be filtered from a wider range of mixed

signals. Filter circuits can be designed to accomplish this taskby combining the properties of low-pass and high-pass into a

single filter which is a band-pass filter.


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What is band-pass filter ?A filter designed to transmit a particular

band of electromagnetic frequencies while

excluding those of higher or lower

frequencies.

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Active Band-Pass Filter

Created by connectingoutput of a high-pass filter

to the input of a low-passfilter or vice versa.

Also can create using only1 op-amp with feedbackand input capacitors.

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Active Band-Pass Filter Note that the fact that the high-pass section

comes first in this design instead of the low-pass

section makes no difference in its overalloperation. It will still filter out all frequencies too

high or too low.

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An example of designing a

band-pass filter To design this band-pass

filter we should specify the

range of frequenciesand apply the following

relations and fix either the

value of the resistor of the

capacitor:

and

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An example of designing a

band-pass filter (Continued): The desired range of frequencies is between 10KHz and

50KHz.

We fixed the value of the capacitor at 10nF becauseresistors are more available and can be modeled easily.

We apply the previous relations to get the value of the

resistors:

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Frequency response

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A simulationforthe previous

exampleusingmultisim


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Theu

sage of Band-pass filters: Personal Radios

Wireless Routers

Cell Phones

Televisions

DSL Modems

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Summary:

A band-pass filter is a device that passes frequencies within

a certain range and rejects (attenuates) frequencies outside

that range.

Attenuate means to reduce or diminish in amplitude. When

you turn down the volume control on your stereo, you are

attenuating the signal being sent to the speakers.

Band-pass filters can be made by stacking a low-pass filter on

the end of a high-pass filter, or vice versa.

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Thank you for paying attention

If you have any question feel free to ask

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band pass presentation

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