ADS
124
®
2
ADS
124
®
3
ADS1242
ADS1243
SBAS235H – DECEMBER 2001 – REVISED OCTOBER 2013
24-Bit
ANALOG-TO-DIGITAL CONVERTER
FEATURES
q
24 BITS NO MISSING CODES
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SIMULTANEOUS 50Hz AND 60Hz REJECTION
(–90dB MINIMUM)
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0.0015% INL
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21 BITS EFFECTIVE RESOLUTION
(PGA = 1), 19 BITS (PGA = 128)
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PGA GAINS FROM 1 TO 128
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SINGLE-CYCLE SETTLING
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PROGRAMMABLE DATA OUTPUT RATES
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EXTERNAL DIFFERENTIAL REFERENCE
OF 0.1V TO 5V
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ON-CHIP CALIBRATION
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SPI™ COMPATIBLE
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2.7V TO 5.25V SUPPLY RANGE
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600µW POWER CONSUMPTION
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UP TO EIGHT INPUT CHANNELS
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UP TO EIGHT DATA I/O
DESCRIPTION
The ADS1242 and ADS1243 are precision, wide dynamic
range, delta-sigma, analog-to-digital (A/D) converters with
24-bit resolution operating from 2.7V to 5.25V supplies.
These delta-sigma, A/D converters provide 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 a very high input impedance for direct
connection to transducers or low-level voltage signals. Burn-
out current sources are provided that allow for the detection
of an open or shorted sensor. An 8-bit digital-to-analog
converter (DAC) provides an offset correction with a range of
50% of the FSR (Full-Scale Range).
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 second-order
delta-sigma modulator and programmable FIR filter that pro-
vides 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
ADS1242 and ADS1243 are designed for high-resolution
measurement applications in smart transmitters, industrial
process control, weight scales, chromatography, and portable
instrumentation.
V
DD
V
REF+
V
REF–
X
IN
X
OUT
APPLICATIONS
q
q
q
q
q
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INDUSTRIAL PROCESS CONTROL
LIQUID /GAS CHROMATOGRAPHY
BLOOD ANALYSIS
SMART TRANSMITTERS
PORTABLE INSTRUMENTATION
WEIGHT SCALES
V
DD
Clock Generator
2µA
Offset
DAC
A
IN
0/D0
A
IN
1/D1
A
IN
2/D2
A
IN
3/D3
A
IN
4/D4
A
IN
5/D5
A
IN
6/D6
A
IN
7/D7
MUX
IN+
IN–
BUF
+
PGA
2nd-Order
Modulator
Digital
Filter
Controller
Registers
A = 1:128
ADS1243
Only
2µA
GND
GND
PDWN
Serial Interface
SCLK
D
IN
D
OUT
CS
DRDY
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 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 © 2001-2013, Texas Instruments Incorporated
www.ti.com
TI [ TEXAS INSTRUMENTS ]
