ADS1244
ADS1
244
SBAS273 – DECEMBER 2002
Low-Power, 24-Bit
ANALOG-TO-DIGITAL CONVERTER
FEATURES
q
20-BIT EFFECTIVE RESOLUTION
q
CURRENT CONSUMPTION: 90
µ
A
q
ANALOG SUPPLY: 2.5V to 5.25V
q
DIGITAL SUPPLY: 1.8V to 3.6V
q
±
5V DIFFERENTIAL INPUT RANGE
q
0.0002% INL (TYP), 0.0008% INL (MAX)
q
SIMPLE 2-WIRE SERIAL INTERFACE
q
SIMULTANEOUS 50Hz AND 60Hz REJECTION
q
SINGLE CONVERSIONS WITH SLEEP MODE
q
SINGLE-CYCLE SETTLING
q
SELF-CALIBRATION
q
WELL-SUITED FOR MULTICHANNEL SYSTEMS
q
EASILY CONNECTS TO THE MSP430
DESCRIPTION
The ADS1244 is a 24-bit, delta-sigma Analog-to-Digital (A/D)
converter. It offers excellent performance and very low power
in an MSOP-10 package and is well suited for demanding
high-resolution measurements, especially in portable and
other space- and power-constrained systems.
A 3rd-order delta-sigma modulator and digital filter form the
basis of the A/D converter. The analog modulator has a
±5V
differential input range. The digital filter rejects both 50Hz
and 60Hz signals, completely settles in one cycle, and
outputs data at 15 samples per second.
A simple, 2-wire serial interface provides all the necessary
control. Data retrieval, self-calibration, and Sleep Mode are
handled with a few simple waveforms. When only single
conversions are needed, the ADS1244 can be shut down
(Sleep Mode) while idle between measurements to dramati-
cally reduce the overall power dissipation. Multiple ADS1244s
can be connected together to create a synchronously sam-
pling multichannel measurement system. The ADS1244 is
designed to easily connect to microcontrollers, such as the
MSP430.
The ADS1244 supports 2.5V to 5.25V analog supplies and
1.8V to 3.6V digital supplies. Power is typically less than
270µW in normal operation and less than 1µW during Sleep
Mode.
APPLICATIONS
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HAND-HELD INSTRUMENTATION
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PORTABLE MEDICAL EQUIPMENT
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INDUSTRIAL PROCESS CONTROL
q
WEIGH SCALES
VREFP VREFN
AVDD
DVDD
CLK
DRDY/DOUT
Digital
Filter
Serial
Interface
SCLK
AINP
AINN
3rd-Order
Modulator
GND
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.
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 © 2002, Texas Instruments Incorporated
www.ti.com
BURR-BROWN [ BURR-BROWN CORPORATION ]
