ADS1

251

24-Bit, 20kHz, Low-Power

ANALOG-TO-DIGITAL CONVERTER

FEATURES

q 24 BITS—NO MISSING CODES

q 19 BITS EFFECTIVE RESOLUTION UP TO

20kHz DATA RATE

q LOW NOISE: 1.5ppm

q DIFFERENTIAL INPUTS

q INL: 15ppm (max)

q EXTERNAL REFERENCE (0.5V to 5V)

q POWER-DOWN MODE

q SYNC MODE

q LOW POWER: 8mW at 20kHz

5mW at 10kHz

DESCRIPTION

The ADS1251 is a precision, wide dynamic range, delta-

sigma, Analog-to-Digital (A/D) converter with 24-bit resolu-

tion operating from a single +5V supply. The delta-sigma

architecture features wide dynamic range, and 24 bits of no

missing code performance. Effective resolution of 19 bits

(1.5ppm of rms noise) is achieved at conversion rates up to

20kHz.

The ADS1251 is designed for high-resolution measurement

applications in cardiac diagnostics, smart transmitters, indus-

trial process control, weigh scales, chromatography, and

portable instrumentation. The converter includes a flexible,

2-wire synchronous serial interface for low-cost isolation.

The ADS1251 is a single-channel converter and is offered in

an SO-8 package. It is pin-compatible with the faster ADS1252

(41.7kHz data rate).

APPLICATIONS

q CARDIAC DIAGNOSTICS

q DIRECT THERMOCOUPLE INTERFACES

q BLOOD ANALYSIS

q INFRARED PYROMETERS

q LIQUID/GAS CHROMATOGRAPHY

q PRECISION PROCESS CONTROL

4th-Order

∆Σ

Modulator

Digital

Filter

Serial

Interface

Control

+V

IN

CLK

SCLK

DOUT/DRDY

GND

–V

IN

ADS1251

ADS1251

SBAS184A – MARCH 2001 – REVISED SEPTEMBER 2003

www.ti.com

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

Copyright © 2001-2003, Texas Instruments Incorporated

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

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