1 Features

1• Programmable Data Rates Up to 2 kSPS

• Single-Cycle Settling for All Data Rates

• Simultaneous 50-Hz and 60-Hz Rejection at

20 SPS

• Analog Multiplexer With 8 (ADS1148) and

4 (ADS1147) Independently Selectable Inputs

• Programmable Gain: 1 V/V to 128 V/V

• Dual-Matched Programmable Excitation Current

Sources

• Low-Drift Internal 2.048-V Reference

• Sensor Burnout Detection

• 4 or 8 General-Purpose I/Os (ADS1147 and

ADS1148)

• Internal Temperature Sensor

• Power Supply and VREF Monitoring (ADS1147 and

ADS1148)

• Self and System Calibration

• SPI™-Compatible Serial Interface

• Analog Supply: Unipolar (2.7 V to 5.25 V) or

Bipolar (±2.5 V)

• Digital Supply: 2.7 V to 5.25 V

2 Applications

• Temperature Measurement

– RTDs, Thermocouples, and Thermistors

• Pressure Measurement

• Flow Meters

• Factory Automation and Process Control

3 Description

The ADS1146, ADS1147, and ADS1148 devices are

precision, 16-bit analog-to-digital converters (ADCs)

that include many integrated features to reduce

system cost and component count for sensor

measurement applications. The devices feature a

low-noise, programmable gain amplifier (PGA), a

precision delta-sigma (ΔΣ) ADC with a single-cycle

settling digital filter, and an internal oscillator. The

ADS1147 and ADS1148 devices also provide a builtin,

low-drift voltage reference, and two matched

programmable excitation current sources (IDACs).

An input multiplexer supports four differential inputs

for the ADS1148, two for the ADS1147, and one for

the ADS1146. In addition, the multiplexer integrates

sensor burn-out detection, voltage bias for

thermocouples, system monitoring, and general

purpose digital I/Os (ADS1147 and ADS1148). The

PGA provides selectable gains up to 128 V/V. These

features provide a complete front-end solution for

temperature sensor measurement applications

including thermocouples, thermistors, and resistance

temperature detectors (RTDs) and other small signal

measurements including resistive bridge sensors.

The digital filter settles in a single cycle to support

fast channel cycling when using the input multiplexer

and provides data rates up to 2 kSPS. For data rates

of 20 SPS or less, both 50-Hz and 60-Hz interference

are rejected by the filter.