ADS1247: Resistar value(Rcmp and RBIAS) to ADS1247

user6090335

Part Number: ADS1247
Other Parts Discussed in Thread: ADS1248, ADS124S08, ADS124S06, ADS124S08EVM

I use Pt100 senser (Resistance Temperature Detector).
I want to measure the temperature from -80℃ to 70℃ (Celsius) at ADS1247,
I want to know resistar value Rcomp and RBIAS.

over 3 years ago

0 Collin Wells over 3 years ago

TI__Guru 62095 points

Hello,

Please review the reference designs shown below and they'll provide two methods with the ADS1247. All of the required calculations are included and explained.

http://www.ti.com/tool/TIPD120

http://www.ti.com/tool/TIPD152

0 user6090335 over 3 years ago in reply to Collin Wells

Prodigy 30 points

Hi collin

In this case, I want to use two 3-wire RTDs with one chip.

ADS1248 is used.

ADS1247 is not used ?.

0 Collin Wells over 3 years ago in reply to user6090335

TI__Guru 62095 points

Hello,

That is correct. All 4 of the inputs are used for the RTD measurement with the ADS1247. More sensors could be accommodated with the ADS1248, ADS124S06, or ADS124S08 devices.

I should have linked it in the last post but TI has a great resource on RTD applications that show many options for multi-sensor designs:

http://www.ti.com/lit/an/sbaa275/sbaa275.pdf

0 user6090335 over 3 years ago in reply to Collin Wells

Prodigy 30 points

Thank you collin.

I want to schematic of two 3-wire RTDs at ADS1248 ,ADS124S06 or ADS124S08,
Can I buy a board that measures temperature with two 3-wire RTDs?

0 Collin Wells over 3 years ago in reply to user6090335

TI__Guru 62095 points

Hello,

I'm not sure there's a reference design out there available for purchase with a multi-RTD measurement. However, you can purchase the ADS124S08EVM and connect the RTDs externally. We have some great reference code available as well for temperature sensing with this device which can be found here:

http://www.ti.com/tool/ADC-TEMP-SENSOR-FW

Data converters

Data converters forum

ADS1247: Resistar value(Rcmp and RBIAS) to ADS1247