24-Bit

ANALOG-TO-DIGITAL CONVERTER

FEATURES

q 24 BITS NO MISSING CODES

q SIMULTANEOUS 50Hz AND 60Hz REJECTION

(–90dB MINIMUM)

q 0.0015% INL

q 21 BITS EFFECTIVE RESOLUTION

(PGA = 1), 19 BITS (PGA = 128)

q PGA GAINS FROM 1 TO 128

q SINGLE CYCLE SETTLING

q PROGRAMMABLE DATA OUTPUT RATES

q EXTERNAL DIFFERENTIAL REFERENCE

OF 0.1V TO 5V

q ON-CHIP CALIBRATION

q SPI™ COMPATIBLE

q 2.7V TO 5.25V SUPPLY RANGE

q 600

q UP TO EIGHT INPUT CHANNELS

q UP TO EIGHT DATA I/O

DESCRIPTION

The ADS1240 and ADS1241 are precision, wide dynamic range,

delta-sigma, Analog-to-Digital (A/D) converters with 24-bit resolution

operating from 2.7V to 5.25V power supplies. The delta-sigma A/D

converter provides up to 24 bits of no missing code performance and

effective resolution of 21 bits.

The input channels are multiplexed. Internal buffering can be

selected to provide very high input impedance for direct connection

to transducers or low-level voltage signals. Burnout current sources

are provided that allow for detection of an open or shorted sensor.

An 8-bit Digital-to-Analog (D/A) converter provides an offset cor-

rection with a range of 50% of the Full-Scale Range (FSR).

The Programmable Gain Amplifier (PGA) provides selectable gains of

1 to 128, with an effective resolution of 19 bits at a gain of 128. The

A/D conversion is accomplished with a 2nd-order delta-sigma modu-

lator and programmable Finite-Impulse Response (FIR) filter that

provides a simultaneous 50Hz and 60Hz notch. The reference input

is differential and can be used for ratiometric conversion.

The serial interface is SPI compatible. Up to eight bits of data

I/O are also provided that can be used for input or output. The

ADS1240 and ADS1241 are designed for high-resolution measure-

ment applications in smart transmitters, industrial process control,

weigh scales, chromatography, and portable instrumentation.

APPLICATIONS

q INDUSTRIAL PROCESS CONTROL

q WEIGH SCALES

q LIQUID /GAS CHROMATOGRAPHY

q BLOOD ANALYSIS

q SMART TRANSMITTERS

q PORTABLE INSTRUMENTATION

BUF

PGA

A = 1:128

+

Clock Generator

Serial Interface

2nd-Order

Modulator

AGND

AV

DD

V

X

IN

X

OUT

DSYNC

PDWN

RESET

DRDY

BUFEN

DGND

DV

DD

SCLK

POL

D

IN

D

OUT

CS

MUX

A

A

A

A

A

A

A

A

A

INCOM

Controller

Registers

Digital

Filter

2

µA

AV

DD

Offset

DAC

AGND

2

µA

ADS1241

Only

ADS1

241

ADS1

240

ADS1240

ADS1241

SBAS173F – JUNE 2001 – REVISED OCTOBER 2013

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 © 2001-2006, 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.

All trademarks property of their respective owners.