Can anyone tell me how to reject the power line noise from the signal...
the signal is to weak to detect.
Can someone please suggest me about the best OPAM to work with..
PLEASE HELP!!!!!!!!!! its urgent.....

 

Can anyone tell me how to reject the power line noise from the signal...
the signal is to weak to detect.
Can someone please suggest me about the best OPAM to work with..
PLEASE HELP!!!!!!!!!! its urgent.....

Post your schematic.

Ken

 

You need to use an instrumentation amplifier, you should use twisted shielded pair cables for the signal input, and you may need to drive the shield so that it has an active ground.

You really can't filter out the 60Hz noise from the signal once it gets in there; as 60Hz is too close to the subjects' heartbeat frequency. Make certain that there is no noise on your power supply. Batteries have a very, very low amount of noise; consider using batteries for a supply.

An INA118 or INA128 might be a good choice for an instrumentation amplifier to use.

[eta]
Have a look at the datasheet for the INA128:
http://www.ti.com/lit/ds/symlink/ina128.pdf
On the bottom of page 11, there is an application shown for an ECG amplifier with a driven shield and a driven ground for the patient.
The INA118 datasheet has the same application in the same location:
http://www.ti.com/lit/ds/symlink/ina118.pdf

 

This is not an easy thing to do. The circuit has to be high impedance differential instrumentation opamp with high CMRR. Also circuitry must be isolated for safety reasons. Use batteries.

edit: Wookie still types faster than me. At >20K posts he's had more practice.

 

Hi Ravi
If you go to web site for the major producers of electronics and search for ECG you will find a lot stuff like this one
http://focus.ti.com/pdfs/vf/medeq/informationformedicalapplications.pdf
Try these
http://www.analog.com
http://www.ti.com/
http://www.national.com/
Some of the circuits may have used exotic components. But use the design principals. We may help finding replacement ICs

 

thanx for suggesting me