Help me understand two configurations of ECG circuit

[reyge]

hello! Attached are two circuit configuration that are similar except that one uses a single supply voltage and some capacitor and resistor values. Can someone explain what the right leg drive do? How does the OP97 accomplish this? Will there be a difference between the two circuit configuration aside from the difference in the power supplies?

I could really use some help. Thanks!

 

[FvM]

ecgcircuit

Hello,

the "feedback" tries to zero common mode voltage, this way increasing the common suppression of the differential amplifier und surpressing interference, e. g. from AC power supply.

The second version is an non operating artefact without an appropriate input bias.
The designer should repeat his OP circuit class.

Regards,
Frank

 

[reyge]

ad620 artifact suppression

Hi Frank,

Thanks for the reply! The second version you are referring to is circuit 1.jpg, right? Can you elaborate on how it has no appropriate input bias? I attached the paper where I got the configuration. For the resistor values, do you think the authors just had a typographical error? R6 should be 1M and R5 should be 10k just like those in circuit 2.jpg


Also, the AD620 requires an input voltage range of (-Vs + 1.9) to (+Vs - 1.2). Does the right leg drive assure that the input from the right and left arm will be at this range? Thanks!

 

[hniman]

supply circuit ecg

probably it useful for you

 

[eljaime]

ad620, circuits ecg

hi, very well, i was searchingin others sites, but here too much information of ecg

 

[nymph]

ad620 can not work ecg

oh i am really impressed awith this site!

 

[ranggaperdana_06114]

ecg circuit protection

great bro it's really helpme so much.
but i've question to you
how that can connect to pc and view the result to pc...???
tanx before

 

[zawmintun1]

resistor configuration for ecg

Thank

 

[ranggaperdana_06114]

ecg ad620

i've design the ecg project with AD620 but i don't know it;s correct or not, can you tell me it's correct or not (in attachment).and what i must with the diodes?
tanx

 

[D_A_V_E]

right leg driven circuit

Diodes are for protection.

Circuit should work

 

[ranggaperdana_06114]

basic ecg circuit single supply

so what series of diodes that i must use for that?

 

[mehrdad_58]

Re: supply circuit ecg

probably it useful for you

Could you please send me you link again
I couldn't see it here.
I want to know how it is possible to use AD620 in an ECG device just by one single supply.
Regards