FEATURES

20-Bit Effective Resolution

High-Impedance Buffered Input

±2.5V Differential Input Range

Pin-Compatible with ADS1244

0.0006% INL (typ), 0.0015% INL (max)

Simple Two-Wire Serial Interface

Simultaneous 50Hz and 60Hz Rejection

Single Conversions with Sleep Mode

Single-Cycle Settling

Self-Calibration

Well Suited for Multi-Channel Systems

Easily Connects to the MSP430

Current Consumption: 158μA

Analog Supply: 2.5V to 5.25V

Digital Supply: 1.8V to 3.6V

APPLICATIONS

Hand-Held Instrumentation

Portable Medical Equipment

Industrial Process Control

Test and Measurement Systems

DESCRIPTION

The ADS1245 is a 24-bit, delta-sigma analog-to-digital

converter (ADC). It offers excellent performance and very

low power in an MSOP-10 package and is well suited for

demanding high-resolution measurements, especially in

portable and other space- and power-constrained

systems.

The buffered input presents an impedance of 3GΩ, minimizing

measurement errors when using high-impedance

sources. The ADS1245 is compatible with ADS1244 and

offers a direct upgrade path for designs requiring higher input

impedance.

A third-order delta-sigma (ΔΣ) modulator and digital filter

form the basis of the ADC. The analog modulator has a

±2.5V differential input range. The digital filter rejects both

50Hz and 60Hz signals, completely settles in one cycle,

and outputs data at 15 samples per second (SPS).

A simple, two-wire serial interface provides all the

necessary control. Data retrieval, self-calibration, and

Sleep mode are handled with a few simple waveforms.

When only single conversions are needed, the ADS1245

can be shut down (Sleep mode) while idle between

measurements to dramatically reduce the overall power

dissipation. Multiple ADS1245s can be connected

together to create a synchronously sampling multichannel

measurement system. The ADS1245 is designed to easily

connect to microcontrollers, such as the MSP430.

The ADS1245 supports 2.5V to 5.25V analog supplies and

1.8V to 3.6V digital supplies. Power is typically less than

470μW in normal operation and less than 1μW during

Sleep mode.