OPAMP input disturbed by noise

Status
Not open for further replies.

hardings

Member level 3
Joined
May 23, 2003
Messages
57
Helped
5
Reputation
10
Reaction score
2
Trophy points
1,288
Activity points
501
Hi,

I am designing a circuit, which noise is very serious, I put the noisy input to one input of the OPAMP,
and connect bandgap voltage to the other input, then the noise will increase the bandgap volgate.
Also I do some circuit to eliminate this effect, but my boss said it is too complex, anyone has some
simple ways to design this OPAMP?

Thanks
 

I think your you should design a low noise op amp.
 

That is not my question,

My question is , an OPAMP with two input, one of the input signal is very noisy, and the noise voltage will distorb the value at the other input (bandgap voltage), How can I design the OPAMP to avoid disturbing?
 

maybe you could use a buffer stage to pre-filter the noisy input or putting a capacitor on the bandgap output to filter the coupled noise
 

Usually I will filter the noise source by a low pass filter and then input to the op-amp. So it will not disturb the bandgap voltage.

Yibin.
 

Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…