Part Number: ADS1291
When 1P and 1N (3PIN, 4PIN) of the ADS1291 add series resistances and identification instrument input 5mV sine wave, the value of sine waves obtained from the ECG acquisition will seriously exceed the amplitude.If a small DC component is added to the sine wave of the identification instrument, the sine wave will appear normal; However,adding a DC component directly to the circuit will not work. What is the cause of this?
b. When 1P and 1N (3PIN, 4PIN) of the ADS1291 have capacitances and resistances in series,the value of sine waves is 5 mV and normal,which is read from the identification instrument.However, when collecting or shorting between R and L leads, there is a small protrusion on the ECG line,as shown below. Could you please tell me how to solve the problem of one second fluctuation of capacitance? And what is the reason for this?
I am also in accordance with the recommended figure to debug, the same phenomenon, PCB line is no problem
Precision ΔΣ ADCs
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Alex SmithApplications Engineer | Precision Delta-Sigma Converters
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In reply to Ryan Andrews:
In reply to Alexander Smith:
In reply to en-chao liu:
Hello En-Chao, Did Ryan's answer solve the common mode problem? Are you having trouble configuring the gain settings of the device? I don't fully understand the issue that you are having. Can you please explain in further detail? Is this voltage going to the 1P and 1N (3PIN, 4PIN) of the device? What is the magnitude? Are the input pin limitations being exceeded due to the common mode issue?
Hello Alexander Smith:
1.Did Ryan's answer solve the common mode problem?
RLDOUT connection to 1 p, 1N pin is not connected,I also don't connection to RLDOUT, The same phenomenon.
2.Are you having trouble configuring the gain settings of the device?
I can.but, I didn't set gain Settings.
I don't fully understand the issue that you are having. Can you please explain in further detail? Is this voltage going to the 1P and 1N (3PIN, 4PIN) of the device? What is the magnitude? Are the input pin limitations being exceeded due to the common mode issue?
Look at the picture
I set sine wave 0.3mV, no problem.
There's no problem in the other waves ，There is sine wave wrong
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