ADS1261: power supply

Daria Kiseleva

Part Number: ADS1261

Tool/software:

Good day, colleagues,

Does the supply voltage of the resistor bridge have to be precise, or is a switching regulator sufficient there?

Do the AVDD potential of the ADS1261 and the supply of the resistor bridge have to be supplied by the same source or can the AVDD and the supply of the resistor bridge come from different sources?

Thanks,

Daria

over 1 year ago

0 Bryan Lizon86 over 1 year ago

TI__Guru 51906 points

Hi Daria Kiseleva,

Can you please help us track this opportunity by posting the customer name in the Notes section of the Thread Tracking Toolkit?

-Bryan

0 Daria Kiseleva over 1 year ago in reply to Bryan Lizon86

TI__Intellectual 2655 points

Hi Bryan,

Sure,

Sincerely,

Daria

+1 Bryan Lizon86 over 1 year ago in reply to Daria Kiseleva

TI__Guru 51906 points

Hi Daria Kiseleva,

Typically a bridge is measured ratiometrically, where the excitation source for the bridge is the same used for the reference voltage. Then, any variation in the excitation voltage is seen equally in the input signal and the reference, and therefore cancels out

Usually, designers therefore just use the same LDO to power AVDD, the bridge, and the reference, because that it is the simplest solution. But this is not strictly necessary, especially if the bridge excitation voltage is larger than the ADC AVDD voltage. For example, excitation = 10V but the ADC can only support up to 5V

You can reference our resistive bridge design guide for more detailed information: https://www.ti.com/lit/an/sbaa532a/sbaa532a.pdf?ts=1721048595475

-Bryan

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ADS1261: power supply