Description
The ADS1246, ADS1247, and ADS1248 are
highly-integrated, precision, 24-bit analog-to-digital
converters (ADCs). The ADS1246/7/8 feature an
onboard, low-noise, programmable gain amplifier
(PGA), a precision delta-sigma ADC with a
single-cycle settling digital filter, and an internal
oscillator. The ADS1247 and ADS1248 also provide a
built-in, very low drift voltage reference with 10mA
output capacity, and two matched programmable
current digital-to-analog converters (DACs). The
ADS1246/7/8 provide a complete front-end solution
for temperature/bridge sensor applications including
thermal couples, thermistors, RTDs, and strain-gauge
applications.
An input multiplexer supports four differential inputs
for the ADS1248, two for the ADS1247, and one for
the ADS1246. In addition, the multiplexer has a
sensor
burnout
detect,
voltage
bias
for
thermocouples,
system
monitoring,
and
general-purpose digital I/Os
(ADS1247 and
ADS1248). The onboard, low-noise PGA provides
selectable gains of 1 to 128. The delta-sigma
modulator and adjustable digital filter settle in only
one cycle, for fast channel cycling when using the
input multiplexer, and support data rates up to
2kSPS. For data rates of 20SPS or less, both 50Hz
and 60Hz interference are rejected by the filter.
The ADS1246 is offered in a small TSSOP-16
package, the ADS1247 is available in a TSSOP-20
package, and the ADS1248 in a TSSOP-28 package.
All three devices are rated over the extended
specified temperature range of –40°C to +105°C
Specs
24 Bits, No Missing Codes
Data Output Rates Up to 2kSPS
Single-Cycle Settling for All Data Rates
Simultaneous 50/60Hz Rejection at 20SPS
4 Differential/7 Single-Ended Inputs (ADS1248)
2 Differential/3 Single-Ended Inputs (ADS1247)
Low-Noise PGA: 48nV at PGA = 128
Matched Current Source DACs
Very Low Drift Internal Voltage Reference:
10ppm/°C (max)
Sensor Burnout Detection
4/8 General-Purpose I/Os (ADS1247/48)
Internal Temperature Sensor
Power Supply and V
REF
Monitoring
(ADS1247/48)
Self and System Calibration
SPI™-Compatible Serial Interface
Analog Supply Unipolar (+2.7V to
+5.25V)/Bipolar (±2.5V) Operation
Digital Supply: +2.7V to +5.25V
Operating Temperature –40°C to +125°C
Application
Temperature Measurement
– RTDs, Thermocouples, and Thermistors
Pressure Measurement
Industrial Process Contro
