How to generate response file for NI 9229 device

[Emad_NRIAG]

My target is to establish a response file for the 9229 device. Response parameters typically consist of a sensitivity or "gain", measured at some specified frequency, and a set of poles and zeroes for the transfer function that expresses the frequency response of the NI-9229. 

The 9229 is a 24-bit ADC, and note that there is only one input range, +/- 60 V, on the 9229.  So, per that equation, (120 V)/([2^24] - 1) = ~7.2 uV we can calculate the sensitivity. However, for poles and zeros, I can't find any information in the manual about them. Kindly, how to solve this problem.

[GerdW]

Hi Emad,

---

@Emad_NRIAG wrote:

Response parameters typically consist of a sensitivity or "gain", measured at some specified frequency, and a set of poles and zeroes for the transfer function that expresses the frequency response of the NI-9229. 

However, for poles and zeros, I can't find any information in the manual about them. Kindly, how to solve this problem.

---

Well, in the datasheet for the NI9229 you will find explicit information on passband and stopband characteristics!

There's a whole chapter on filtering behaviour and a lot of numbers in the specs section…

Do you need more information?

[Emad_NRIAG]

Thanks, Mr. GerdW for your cooperation. Yes, I need more information if you have. Or how to use these information to calculate poles and zeroes (transfer function) for NI-9229 device?

[GerdW]

Hi Emad,

---

@Emad_NRIAG wrote:

how to use these information to calculate poles and zeroes (transfer function) for NI-9229 device?

---

It's been a while since I had to calculate transfer functions using poles/zeros - maybe 20 years ago.

So I guess you have some books explaining those calculations and you got trained to apply them!

The datasheet mentions

• a passband frequency of 0.453*fs with a flatness of <= 0.1dB
• a stopband frequency of 0.547*fs with rejection of >=100dB

There surely are formulas to convert those numbers into poles/zeros in the imaginary plane…