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
WEIGH SCALES
LIQUID/GAS CHROMATOGRAPHY
BLOOD ANALYSIS
SMART TRANSMITTERS
PORTABLE INSTRUMENTATION

DESCRIPTION
The ADS1240 and ADS1241 are precision, wide dynamic range,
delta-sigma, Analog-to-Digital (A/D) converters with 24-bit resolution
operating from 2.7V to 5.25V power supplies. The delta-sigma A/D
converter provides 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 very high input impedance for direct connection
to transducers or low-level voltage signals. Burnout current sources
are provided that allow for detection of an open or shorted sensor.
An 8-bit Digital-to-Analog (D/A) converter provides an offset correction
with a range of 50% of the Full-Scale Range (FSR).
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 2nd-order delta-sigma modulator
and programmable Finite-Impulse Response (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
ADS1240 and ADS1241 are designed for high-resolution measurement
applications in smart transmitters, industrial process control,
weigh scales, chromatography, and portable instrumentation.