Jehan, First, there are two basic guides on RTD and thermocouple measurement. If you have already seen them, great. However, if you haven't, they can be found here: A Basic Guide to RTD Measurements: www.ti.com/.../sbaa275.pdf A Basic Guide to Thermocouple Measurements: www.ti.com/.../sbaa274.pdf In particular, the RTD measurements guide has a schematic for a "Universal RTD Measurement Interface with Low-Side Reference" that could be used for an interface. Go to the schematic shown on page 35 of the RTD note. It shows a connector that can be used for a 2-, 3-, and 4-wire RTD. In addition to this, you could use AIN1 and AIN2 for the inputs of the thermocouple. Then disable the IDAC currents, use a VBIAS connection for AIN2, and enable the internal reference for the ADC. This would be similar to the schematic on page 21 of the thermocouple measurement. Regardless of whatever decide to design, I would try to test the measurements with an EVM. The ADS1148EVM-PDK is available, but was designed in the Windows XP era. It should work systems up to Windows 7, but there may be setup issues with newer systems. Another similar device is the ADS124S08 . This is the next generation of the ADS1248 and also comes in a 16-bit version as the ADS114S08 . The ADS124S08EVM would be a good starting point to make these test measurements. Joseph Wu
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