24-Bit, 20kHz, Low Power
ANALOG-TO-DIGITAL CONVERTER
FEATURES
a71 24 BITS—NO MISSING CODES
a71 19 BITS EFFECTIVE RESOLUTION UP TO
20kHz DATA RATE
a71 LOW NOISE: 1.8ppm
a71 FOUR DIFFERENTIAL INPUTS
a71 INL: 15ppm (max)
a71 EXTERNAL REFERENCE (0.5V to 5V)
a71 POWER-DOWN MODE
a71 SYNC MODE
a71 LOW POWER: 4mW at 20kHz
a71 SEPARATE DIGITAL INTERFACE SUPPLY 1.8V
to 3.6V
DESCRIPTION
The ADS1254 is a precision, wide dynamic range, delta-
sigma, Analog-to-Digital (A/D) converter with 24-bit reso-
lution. The delta-sigma architecture is used for wide dy-
namic range and to ensure 24 bits of no missing codes
performance. An effective resolution of 19 bits (1.8ppm of
rms noise) is achieved for conversion rates up to 20kHz.
The ADS1254 is designed for high-resolution measurement
applications in cardiac diagnostics, smart transmitters, in-
dustrial process control, weight scales, chromatography, and
portable instrumentation. The converter includes a flexible,
two-wire synchronous serial interface for low-cost isolation.
The ADS1254 is a multi-channel converter and is offered in
an SSOP-20 package.
APPLICATIONS
a71 CARDIAC DIAGNOSTICS
a71 DIRECT THERMOCOUPLE INTERFACES
a71 BLOOD ANALYSIS
a71 INFRARED PYROMETERS
a71 LIQUID/GAS CHROMATOGRAPHY
a71 PRECISION PROCESS CONTROL
ADS1254
SBAS213 – JUNE 2001
4th-Order
∆Σ
Modulator
Digital
Filter
Serial
Interface
Control
CLK
V
REF
SCLK
DOUT/DRDY
AV
DD
DV
DD
AGND
DGND
ADS1254
Mux
CH1+
CH1–
CH2+
CH2–
CH3+
CH3–
CH4+
CH4–
CHSEL0 CHSEL1
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, 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.
ADS1254