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Hello,
I am using a 24V DC supply in my circuit.
I am trying to design a circuit to measure the noise on the 24V.
The noise expecting is 200mV to 400mV peak to peak.
Could you please suggest any circuit to measure the noise.
The flow will be.
24V ---> Noise measurement circuit ----> ADC.
I am attaching a block diagram for reference.
Regards,
Tensil Sebastian
Hi Tensil,
There are a lot of ways to do this. Can you please clarify a few additional things for us to get started?
Do you have an accuracy requirement for this measurement?
Do you have a sample rate requirement?
Are you looking for a single-channel ADC or do you have additional lines to measure?
Does the measurement needs to be isolated?
Hello Alex,
Thanks for the update.
Please find my comment inline.
Do you have the accuracy required for this measurement?
There is no accuracy requirement in perticular. Better the good.
Do you have a sample rate requirement?
I am connecting this noise measurement to High-speed ADC
Part No: ADS62P25
Sampling rate: 125MSPS
Resolution : 12bits
Are you looking for a single-channel ADC or do you have additional lines to measure?
The input for the ADC will be differential input.
ADC has 2 channels and in one channel I am planning to connected this noise measurement through a mux because I need to measure some other signals also. In the second channel some other signal as well.
In my design, I have some low-speed ADC also. which is 1.6MHz, 16bit, 8 channel. which ADC will be better for this noise measurement.
Does the measurement need to be isolated?
No
Regards,
Tensil Sebastian
Hi Tensil,
Depending on the frequency of the noise to be measured will determine which ADC would be more appropriate. Nyquist theorem requires the sample rate to be at least 2x the signal being measured, where higher sampling rates allow for additional decimation/averaging, increasing the accuracy of the measurement.
Since it sounds like you do not need an ADC, I am going to move this post over to the high speed amplifier forum where they should be able to help you condition the input signal to match your chosen ADCs.
Hello Tensil,
As Alexander mentioned, we would need to know the expected frequency range of the signal. Looks like here you are looking to use a differential input ADC, so this amplifier would need to be a fully differential amplifier for efficient interfacing to this ADC.
Thank you,
Sima