ADS1298

Giuseppe Landolfi

Other Parts Discussed in Thread: ADS1298

Greetings,

I saw that in the "NOISE MEASUREMENTS" section, of the ADS1298 datasheet, in the tables there is a column that describes the -3dB bandwidth.

I'd like to know if these frequencies are the maximum sampling frequency, or if they are the cutoff frequencies of a low pass filter?

Thank you

Giuseppe

over 14 years ago

0 Tom Hendrick over 14 years ago

TI__Guru**** 180961 points

Giuseppe,

The ADS1298 is a delta-sigma converter and it is actually sampling at ~2.048MHz for the values listed in Tables 1-4. The -3dB column is the roll off of the SYNC filter (see page 25). The column to the left is the effective data rate.

0 Giuseppe Landolfi over 14 years ago in reply to Tom Hendrick

Prodigy 100 points

Hi,

if I set the ads1928 for 2000 sps, does the SYNC filter cut really the signal high frequencies at 524Hz? Or need I an external lowpass filter?

thank you!

Giuseppe

0 Tom Hendrick over 14 years ago in reply to Giuseppe Landolfi

TI__Guru**** 180961 points

Hi Giuseppe,

The SYNC filter will allow high frequencies to alias back into your passband, you would need to use an external lowpass ahead of the ADS1298.

Data converters

Data converters forum

ADS1298