ADS124S08:Data converters forum

Hi Kiyoshi Kogure,

I highly recommend that you review A Basic Guide to RTD Measurements.  This document has many useful circuits and explanations.

KIYOSHI KOGURE said:

①Question about power supply

• Digital Supply: 2.7 V to 3.6 V

・Analog Supply: Unipolar (2.7 V to 5.25 V)

In Figure 113. AVDD = 5V

Is there any problem when AVDD=3.3V?

Why is AVDD = 5V set in Figure 113.？

You can use 3.3V for AVDD, but your total current path must stay within the IDAC compliance.  Reviewing A Basic Guide to RTD Measurements will explain both high-side and low-side application circuits.

KIYOSHI KOGURE said:

②Questions about 3-Wire RTD measurements

The sensor has 3 wires

Do I need two ADS124S08 to measure two sensors?

A Basic Guide to RTD Measurements will demonstrate how to connect more than one RTD to a single ADS124S08.

KIYOSHI KOGURE said:

③Question about connection of ADS124S08

I need to measure 8 sensors

Is it possible to connect 8 ADS124S08 to a microcomputer?

Can 8 ADS124S08s be daisy chained to a microcontroller?

The ADS124S08 is not daisy chainable, but you can connect multiple ADS124S08 to a single microcontroller as shown in the diagram you provided.  This requires multiple GPIO to be used for CS of the devices.

KIYOSHI KOGURE said:

④Question about connection of ADS124S08

Use AMIC110 as host

Can ADS124S08 and AMIC110 be daisy chained?

The AMIC110 can be used to communicate to the ADS124S08 through the SPI peripheral.

Best regards,

Bob B