Ecg System

ECG SYSTEM

INTRODUCTION

The ECG is one of the therapeutic equipment that can gauge the heart rate, change over it into a sign and present the information on a bit of paper or on a screen. An ECG is a recording of the electrical action on the body surface produced by the heart. ECG estimation data is gathered by electrodes put at assigned areas on the body. As the heart performs its capacity of pumping blood through the circulatory framework, the aftereffect of the activity possibilities in charge of the mechanical occasions inside the heart is the era of a certain arrangement of electrical occasions. It is the most ideal approach to gauge and diagnose irregular rhythms of the heart.

CONSTRUCTION

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BLOCK DIAGRAM:

  ELECTRODES[pic 2]

[pic 3][pic 4][pic 5]

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HARDWARE:[pic 7]

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                                                                        ANALOG SIGNAL[pic 11][pic 12]

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                                                                        DIGITAL SIGNAL[pic 14][pic 15]

SOFTWARE:

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                                              OUTPUT (DISPLAY)

HARDWARE:

[1] INSTRUMENTATION AMPLIFIER:

[pic 17]

R1 = 9.86Kohm

R2 = 9.73Kohm

R3 = 19.7Kohm

Rgain = 498.7Ohm

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An instrumentation amplifier is generally the first stage in an instrumentation framework. This is a result of the little voltages generally got from the tests need to be enhanced altogether to be continuing stages. An instrumentation Amplifier (IA) is a difference amplifier where the difference between the two data terminals is enhanced and the common signal between the inputs are rejected (Common Mode Rejection (CMR)).

[2] NOTCH FILTER:

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Center frequency: 60Hz

Fd: 80%

C1=C2= 100nF (98nF, 98nF)

C3= 200nF (216nF)

R1=R2= 26.5Kohm

R3=13.3Kohm

R4= 20Kohm

R5= 80Kohm

Q= 1.25

Bandwidth - 48

Notch Filter consolidates both high and low pass channels to make a little district of frequencies to be uprooted. For ECGs, the primary target is to remove 50Hz or 60Hz noise.

[3] LOW PASS FILTER

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A low pass filter is regularly found in electronic circuits, and works by reducing high frequency parts. The most widely recognized manifestation of an equipment low pass filter is a basic arrangement resistor/ capacitor: at low frequencies the capacitor is high impedance in respect to the resistor, however as the frequency builds the capacitor impedance drops and output falls.