ADS1251
ADS
125
1
SBAS184A – MARCH 2001 – REVISED SEPTEMBER 2003
24-Bit, 20kHz, Low-Power
ANALOG-TO-DIGITAL CONVERTER
FEATURES
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24 BITS—NO MISSING CODES
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19 BITS EFFECTIVE RESOLUTION UP TO
20kHz DATA RATE
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LOW NOISE: 1.5ppm
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DIFFERENTIAL INPUTS
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INL: 15ppm (max)
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EXTERNAL REFERENCE (0.5V to 5V)
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POWER-DOWN MODE
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SYNC MODE
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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
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CARDIAC DIAGNOSTICS
DIRECT THERMOCOUPLE INTERFACES
BLOOD ANALYSIS
INFRARED PYROMETERS
LIQUID/GAS CHROMATOGRAPHY
PRECISION PROCESS CONTROL
ADS1251
V
REF
CLK
+V
IN
–V
IN
4th-Order
∆Σ
Modulator
SCLK
DOUT/DRDY
+V
DD
GND
Control
Digital
Filter
Serial
Interface
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
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
www.ti.com
TI [ TEXAS INSTRUMENTS ]
