OPA2140: How can I characterize (practically) the circuit with respect to Noise

Rahul Ramachandran

Part Number: OPA2140

We have realized a TIA card using OPA2140. We did the frequency response of the card. How can I characterize (practically) the circuit with respect to Noise. I mean I need to get the parameters like thermal noise floor, corner frequency etc, SNR etc. I have gone through the Application reports SBOA122, SBOA55A, SBOA942 and SBOA060. But they mention theoretical calculations only. Please help me with this.

over 5 years ago

0 Thomas Kuehl over 5 years ago

TI__Guru* 93105 points

Hi Rahul,

I was not able to find TI Application Reports SBOA55A or SBOA042, but the other two you mention provide very good technical information about the noise characteristics of transimpedance amplifiers.

The best resource that we have regarding op amp noise measurments is the TI Precision Labs - Op amps materials. Session #8.7 (TIPL 1317) discusses pratical noise measurement methods. The results achieved with these measurements methods are supported by calculations and simulations presented in the other Precision Labs noise sessions.

Additionally, if you have access to an audio analyzer such as an Audio Precision ApX555 you can capture some of the noise information that you are interested in obtaining. See the following AP note:

Regards, Thomas

Precision Amplifiers Applications Engineering

0 Dennis Goeke over 5 years ago in reply to Thomas Kuehl

TI__Genius 11135 points

Rahul

We haven't heard back from you so we assume this answered your questions. If not, post another reply below.

Thanks
Dennis

Amplifiers

Amplifiers forum

OPA2140: How can I characterize (practically) the circuit with respect to Noise