Analog summing amplifier

Ubaid Ponnary

Prodigy 20 points

Hello,

i want to design a summing amplifier to sum up four AC signals (3 Vpp each) of same freq but very low.

Signals are from 4 diff sensors and so the frequency of the signals can vary from 1 Hz to 100 Hz.

Low noise is also critical for the application.

can someone suggest me which opamp IC would be perfect for this application.

Thank you in adavnce,

over 11 years ago

0 Bonnie Baker - WEBENCH Design Center over 11 years ago

TI__Expert 3555 points

Uvaid,

This is a very straight forward circcuit. You can accomplish you task with one amplfier and 5 resitors. Before I can recommend an amplifier I need to know a little more. Is this a single or dual supply application? What power supplies do you plan to use for your amplifier?

0 Ubaid Ponnary over 11 years ago in reply to Bonnie Baker - WEBENCH Design Center

Prodigy 20 points

Hello,

Thanks for your reply. Yeah I know its a very strait forward circuit, I used LM 258 because of its availability here but the output was chopped from 0 giving no negative signal.

my sensor circuit use a single supply of 5V but the expected output should swing between ±12 V, opamp needs a dual supply to operate in this range as far as I know. so I am trying to separate the amplir circuit from the sensor design. If its possible with a single supply that would be awesome.

0 Bonnie Baker - WEBENCH Design Center over 11 years ago in reply to Ubaid Ponnary

TI__Expert 3555 points

Ubaid,

Yes it would be awesome if you had an amplifier that had an output swing beyond the power supply rail, however, we do not have such a device in our product offerings. I suggest you find an amplifier that can handle a +/- 15 V supply and design your circuit from there.

Amplifiers

Amplifiers forum

Analog summing amplifier