Can't get ECG signal from ADS1298R except ch1

Hi,

The app engineer was out for business travel, shall get back to you around 7/28.

Hi， 

  Can you share the app engineer's email or other communication methods for a more detailed discussion?

Hi,

Are you using ADS1298EVM and GUI as is and by default?

See if you can see and set the GUI shown below -

Set registers to mux/assign internal test signals to PGA first -

All other settings should remain default as they are when you launch the GUI.

Compare your register settings with below-

Go to the following page and click acquire -

you should see some square wave test signals -

Thanks

Make sure you could see above before proceed further.

Hi,

We are using the ADS1298RECGFE-PDK and the PDK works well. I also can get the square wave test signals with your advice.

The issue is that we can't get the square wave signals with the above setting in our board. It is still full-scale data.

What do you think might be the cause?

Thanks!

Hi, 

The result is as follows:

ch1: Red Line, square wave

ch2: Green Line, no square wave (Similar wih ch3-ch8)

Can your board read the device ID correctly?
Did you do a proper power up and reset sequence with your board?
And can you read&write&read back the registers settings accordingly?
Thanks

To Get square wave in other channels, you will also need to set/configure other channels' mux to Test Signal.

1. Can your board read the device ID correctly?

> Yes, we can.

2. Did you do a proper power up and reset sequence with your board?

> Yes, we can. And we can get the respiration signal in ch1

3. And can you read&write&read back the registers settings accordingly?

> Yes, we can. With the debug mode or the AT mode, we all can get the register setting

4. To Get square wave in other channels, you will also need to set/configure other channels' mux to Test Signal.

> We used the same setting as you advised. And we checked it work on the PDK board

Ok.

So, are you saying that after you configured each channel same as Channel 1 for Internal Test signal(square wave), you can only see square wave in Channel 1?

 Thanks

Hi

Currently, we can get the square waveform in 8 channels. Maybe there are some mistakes in spi before.

Thanks

Hi,

1. When using 5 leads, must RL, V1, and RA, LA, LL be used, or can V2, V3, and RA, LA, LL be used?

2. Now, the ch1, ch2 and ch3 data are normal. But the v2 or v3 has no signal and data are always 0x7fffff.

And the PDK data in ch4 or ch5 are normal with v2 or v3.

The data is as blows

Thanks

Hi,

1. Can you clarify what you mean by 5 leads?  People sometime miscommunication the leads with electrodes.

It would be more clear, what and how many electrodes do you plan to use?  Usually, RA, LA, LL and RLD are must.

2. If you want to get signals from chest electrodes, e.g. v2 and v3,  you will need to use WCT.

Thanks

Hi,

As I know, the 3-leads are RA, LA, and LL. And the 5-leads are RA, LA, LL, RL, and V2(or V3). Is it Right?

With RA, LA, and LL:
 - The PDK can work well and get clear ECG signals

 - Our board can't get a clear ECG signal(has many noise). The signal will clear if we touch the ground of the ECG board or with the RL lead.

So, the minimal system must need RA, LA, LL, and RL? 

Thanks

3 primary leads need RA, LA, and LL electrodes + RLD.

5 leads could depend on people/product/application, but usually need the 3 primary leads that need RA, LA, and LL electrodes + RLD, AND 2 other Vx electrodes around the chest, where x could be 1 ~ 6 depending on the people/product/application.

 "the minimal system must need RA, LA, LL, and RL?"

  Not necessary, it depends on the product&application, there is also one lead(two electrodes) system, which uses only RA-LL or LA-LL and RLD.

"The signal will clear if we touch the ground of the ECG board or with the RL lead." 

This could be expected,

when you touch the PCBA - it seems that a pseudo/face RLD is contacting/driving to your body.

when you touch/connect the RLD - it's a true RLD driving the common mode voltage to your body and also help suppress the noises.

Hi,

1. Unstood the 3-leads usage.

2. If we want to use 5 leads, what configuration does WCT need and is there a recommended configuration?

Thanks!

Hi

Typically WCT is created by RA, LA and LL.

Thanks