AD
S1
25
1
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: 1.5ppm
a71 DIFFERENTIAL INPUTS
a71 INL: 15ppm (max)
a71 EXTERNAL REFERENCE (0.5V to 5V)
a71 POWER-DOWN MODE
a71 SYNC MODE
a71 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
a71 CARDIAC DIAGNOSTICS
a71 DIRECT THERMOCOUPLE INTERFACES
a71 BLOOD ANALYSIS
a71 INFRARED PYROMETERS
a71 LIQUID/GAS CHROMATOGRAPHY
a71 PRECISION PROCESS CONTROL
4th-Order
∆Σ
Modulator
Digital
Filter
Serial
Interface
Control
+V
IN
CLK
V
REF
SCLK
DOUT/DRDY
+V
DD
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
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