FEATURES
24 BITS NO MISSING CODES
SIMULTANEOUS 50Hz AND 60Hz REJECTION
(–90dB MINIMUM)
0.0015% INL
21 BITS EFFECTIVE RESOLUTION
PGA = 1), 19 BITS (PGA = 128)
PGA GAINS FROM 1 TO 128
SINGLE-CYCLE SETTLING
PROGRAMMABLE DATA OUTPUT RATES
EXTERNAL DIFFERENTIAL REFERENCE
OF 0.1V TO 5V
ON-CHIP CALIBRATION
SPI™ COMPATIBLE
2.7V TO 5.25V SUPPLY RANGE
600μW POWER CONSUMPTION
UP TO EIGHT INPUT CHANNELS
UP TO EIGHT DATA I/O

APPLICATIONS
INDUSTRIAL PROCESS CONTROL
LIQUID/GAS CHROMATOGRAPHY
BLOOD ANALYSIS
SMART TRANSMITTERS
PORTABLE INSTRUMENTATION
WEIGHT SCALES

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. Burnout
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 provides
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.