ECG two electrode mode - AD8232

Using Arduino Sensors
1

Hi, I would like to know, how can I use the two electrode mode with this particular sensor. AD8232 What steps do I have to follow.
I have read in the datashet the following sections "Right Leg Drive Amplifier", "AC Leads Off Detection" and "Heart Rate Measurement Next to the Heart" , but I could not understand the setup for this "two electrode mode".
Is there someone in this forum who have accomplished to work with this "two electrode mode"?

I will appreciate every help and experience I can get from the forum-members

Thank you very much in advance

@gkekask Did you find any solution

2

What is the most complex project you have completed where YOU wrote ALL the code?

3

I moved your topic to an appropriate forum category @sanuthi.

In the future, please take some time to pick the forum category that best suits the subject of your topic. There is an "About the _____ category" topic at the top of each category that explains its purpose.

This is an important part of responsible forum usage, as explained in the "How to get the best out of this forum" guide. The guide contains a lot of other useful information. Please read it.

Thanks in advance for your cooperation.

4

Figure 62 shows the schematic. What don't you understand?

1 Like
5

I am trying to get the ECG signal out of two electrodes but it provide me an output with noise. When I get ECG from 3 electrodes I am getting output clearly. My requirement is to get ECG from only 2 Electrode

Thank you

6

Maybe it's not designed to work that way. Does this ring a bell?

long lead

length makes the system susceptible to common-mode inter-

ference. A very narrow band-pass characteristic is required to

separate the heart signal from the interferers.

7

The electrodes have to be placed together and close to the heart with short leads. You should not move around with the two electrode set-up, otherwise you will get motion artifacts (noise)

8

Hi @jim-p

Could you elaborate more on short leads, I am getting perfect ECG from three electrodes, the challenge is to get from 2 electrodes only.

9

According to the data sheet the AD8232 need to be located close to the chest, so I would think 25cm or less.

Did you build your circuit according to the schematic shown in figure 62?

10

This is the set up we have followed

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11

According to the data sheet, in 2-wire mode, the recommendation is to build the circuit, including electrodes in a small puck which is placed right over the heart and the pectoral muscles.

The 3-wire setup includes some filtering not used in the 2-wire setup. That and your long electrode leads probably probably account for the noise difference.

12

When the electrodes are on the hands, the 3-wire mode is recommended.

13

See this topic

I explain about the resistors.

14

Unless you implement the digital signal processing mentioned in that paper, your signal will look like that shown in figure 5

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15

Do you have the SparkFun breakout board or a different one? If different, post the schematic or a link to it.

SparkFun board:

AD8232_Heart_Rate_Monitor_v10.pdf (87.1 KB)

16

Are you working with @sathira_27

17

It appears that the cited paper means for you to hook it up like this:

Screenshot 2024-08-04 at 1.50.43 PM
Screenshot 2024-08-04 at 1.50.43 PM748×568 103 KB

if you have the SparkFun board.

18

Yes

19

Hello,

I am currently working with the AD8232 Heart Rate Monitor sensor from Sparkfun and an Arduino Uno Rev 3 trying to obtain an ECG signal using only 2 electrodes (LA, RA) without using the ground electrode (RL). Instead of the ground electrode I am trying to use 2 10MΩ resistors to create a low impedance path.

I am trying to recreate what is done in the following research paper:

image
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image
image1269×327 63.5 KB

I am currently struggling with where to connect the 2 resistors as I am not that familiar with this kind of setups. Any help is appreciated.

Thanks!

20

They connect between RA and RL and LA and RL
You need to be very very still for that set-up to work.