Description:

The ADS1246, ADS1247, and ADS1248 devices areprecision, 24-bit analog-to-digital converters (ADCs)that include many integrated features to reducesystem cost and component count for sensormeasurement applications. The devices feature alow-noise, programmable gain amplifier (PGA), aprecision delta-sigma (ΔΣ) ADC with a single-cyclesettling digital filter, and an internal oscillator. TheADS1247 and ADS1248 devices also provide a builtin, low-drift voltage reference, and two matchedprogrammable excitation current sources (IDACs).An input multiplexer supports four differential inputsfor the ADS1248, two for the ADS1247, and one forthe ADS1246. In addition, the multiplexer integratessensor burn-out detection, voltage bias forthermocouples, system monitoring, and generalpurpose digital I/Os (ADS1247 and ADS1248). ThePGA provides selectable gains up to 128 V/V. Thesefeatures provide a complete front-end solution fortemperature sensor measurement applicationsincluding thermocouples, thermistors, and resistancetemperature detectors (RTDs) and other small signalmeasurements including resistive bridge sensors.The digital filter settles in a single cycle to supportfast channel cycling when using the input multiplexerand provides data rates up to 2 kSPS. For data ratesof 20 SPS or less, both 50-Hz and 60-Hz interferenceare rejected by the filter.

Features:

• Programmable Data Rates Up to 2 kSPS

• Single-Cycle Settling for All Data Rates

• Simultaneous 50-Hz and 60-Hz Rejection at 20SPS

• Analog Multiplexer With 8 (ADS1248) and 4(ADS1247) Independently Selectable Inputs

• Low-Noise PGA: 48 nVRMS at PGA = 128

• Dual-Matched Programmable Excitation CurrentSources

• Low-Drift Internal 2.048-V Reference:10 ppm/°C (Maximum)

• Sensor Burn-Out Detection

• 4 or 8 General-Purpose I/Os (ADS1247,ADS1248)

• Internal Temperature Sensor

• Power Supply and VREF Monitoring (ADS1247,ADS1248)

• Self and System Calibration

• SPI™-Compatible Serial Interface

• Analog Supply: Unipolar (2.7 V to 5.25 V) andBipolar (±2.5 V) Operation

• Digital Supply: 2.7 V to 5.25 V

Applications:

• Temperature Sensor Measurements:– RTDs, Thermocouples, and Thermistors

• Pressure Measurements

• Flow Meters

• Factory Automation and Process Controls