ADS1261: Data output rate

Esther Lee

Part Number: ADS1261
Other Parts Discussed in Thread: ADS1260

Hi,

I need some help in calculating the data output rate for the ADS1261. I've looked at the conversion latency table but I'm not sure how to relate that to the data output rate as there's no mention of the mux-switching time. If I have 5 pairs of differential inputs, how would I go about calculating the overall data output rate assuming I send a start signal for every input pair I read?

over 2 years ago

0 Bryan Lizon86 over 2 years ago

TI__Guru 54136 points

Hi Esther Lee,

The mux switching time would be negligible in most cases, it occurs almost instantaneously relative to the actual conversion latency

Please review the following app note for more information. Section 8 provides many examples, some of which use the ADS1261: https://www.ti.com/lit/pdf/sbaa535

-Bryan

0 Esther Lee over 2 years ago in reply to Bryan Lizon86

Prodigy 70 points

Hi Bryan,

Thanks for the advice. May I just confirm that the 40000ksps setting can only run with the sinc5 filter? Also, the 3 differential input pairs of the ADS1260 are AIN0 & AIN1, AIN2 & AIN3, AIN4 & AINCOM?

0 Bryan Lizon86 over 2 years ago in reply to Esther Lee

TI__Guru 54136 points

Hi Esther Lee,

Correct, the sinc5 filter is only used with the 40kSPS data rate (not 40000kSPS, or 40MSPS).

The input multiplexer on the ADS1260 is fully flexible, so you can choose any combination of input pins as your differential pairs. For example, you can choose AIN1 and AIN4, or AINCOM and AIN0. In other words, you are not limited to selecting specific groups of channels.

-Bryan

0 Esther Lee over 2 years ago in reply to Bryan Lizon86

Prodigy 70 points

Hi Bryan,

right, I meant 40kSPS, not 40000ksps, sorry about the typo. Thanks for the clarifications!

0 Bryan Lizon86 over 2 years ago in reply to Esther Lee

TI__Guru 54136 points

Hi Esther Lee,

Glad we could help

-Bryan

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ADS1261: Data output rate