MSP430I2041: SD24 Frequency Response

Jan Burgemeister

Part Number: MSP430I2041
Other Parts Discussed in Thread: ADS1248, AMC1304M05, MSP430F67641

Hello,

I am looking for a frequency response curve of the ADC SD24 from zero up to sample frequency. Figure 13-4 of the user's guide is not precise enough for calculating the error in the passband.

Regards

Jan

over 7 years ago

0 Danny F over 7 years ago

Genius 3850 points

it depends on the sampling rate that you set the adc at.

0 Jan Burgemeister over 7 years ago in reply to Danny F

Intellectual 565 points

Yes, the sample rate determines the frequency range. But I am interested in the -10 % or the -3 dB limits, for example. For this purpose a frequency response diagram showing only the passband would be useful.

Best regards
Jan

0 James Evans over 7 years ago in reply to Jan Burgemeister

TI__Mastermind 49692 points

Hello Jan,

You may be interested in reading the following blogs, since the MSP430i2041 uses a SINC3 filter.

Delta-sigma ADC digital filter types: sinc filters

Other Parts Discussed in Post: ADS1248 In my last post , I talked about the different types of digital filters commonly used in delta-sigma analog-to-digital converters (ADCs). In this post, let’s focus…

By Brian Pisani over 10 years ago in Archives > Precision Hub

Quantifying harmonic distortion - Effect of sinc3 filter roll off (part 3)

Other Parts Discussed in Post: MSP430F67641 , AMC1304M05 In the second installment of this series , I briefly talked about the attenuation of frequencies due to the sinc 3 digital filter. In this installment…

By Mekre Mesganaw over 8 years ago in Technical articles > Industrial

Regards,

James

MSP Customer Applications

0 Jan Burgemeister over 7 years ago in reply to James Evans

Intellectual 565 points

Thank you, James. The second link shows what I was looking for. I think it would be useful to add figure 2 (amplitude degradation) to the SD24 chapter of MSP430i2xx user guide. TI shows it, for example in the ADS131Exx data sheet (Fig. 23). It would save users like me from disappointments if they see the actual amplitude error at higher frequencies. For the intended application of measurements at harmonics of mains frequency these errors are predictable and can be corrected. But in my application of vibration measurement at unknown frequencies which requires a linear passband, the amplitude degradation is a disadvantage.

Best regards
Jan

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MSP430I2041: SD24 Frequency Response