1 Features
1• 24-bit, high-precision ADCs
– Offset drift: 1 nV/°C
– Gain drift: 0.5 ppm/°C
– Noise: 30 nVRMS (20 SPS, gain = 128)
– Linearity: 2 ppm
• CMOS PGA gain: 1 to 128
• Wide input voltage range: ±7 mV to ±5 V
• Data rate: 2.5 SPS to 40 kSPS
• 2.5-V reference: 2 ppm/°C
• Simultaneous 50-Hz and 60-Hz rejection mode
• Single-cycle settling mode
• Signal and reference monitors
• 5-V or ±2.5-V power supply
• Internal temperature sensor
• Cyclic redundancy check (CRC)
• Excitation current sources
• Sensor burn-out current sources
• Four general-purpose inputs/outputs (ADS1261)
• AC excitation for bridge sensors (ADS1261)
• 5-mm × 5-mm VQFN package

2 Applications
• PLC analog input modules
• Weigh scales and strain-gauge digitizers
• Temperature, pressure measurement
• Lab instrumentation
• Process analytics

3 Description
The ADS1260 and ADS1261 (ADS126x) are
precision, 40-kSPS, delta-sigma (ΔΣ) analog-to-digital
converters (ADCs) that include a programmable gain
amplifier (PGA). The devices also include a precision
voltage reference and internal fault monitors. The
sensor-ready ADCs give a high-accuracy, single-chip
solution for the most demanding measurements, for
example, weigh scales and resistance temperature
detectors (RTDs).
The ADCs contain an input signal multiplexer, a lownoise
PGA (with gains from 1 to 128), a 24-bit ΔΣ
modulator, a precision voltage reference, and a
programmable digital filter.
The high-impedance PGA inputs (1 GΩ) decrease
measurement error due to sensor loading. The
ADS1260 supports three differential or five singleended
inputs. The ADS1261 supports five differential
or ten single-ended inputs. The integrated current
sources simplify the measurement of RTDs.
The flexible digital filter is programmable for singlecycle
settled conversions, while supplying
simultaneous 50-Hz and 60-Hz line cycle rejection.
Signal and reference monitors, a temperature sensor,
and CRC data verification make data reliability better.
The ADS126x are pin compatible devices given in a
5-mm × 5-mm VQFN package and are specified
across the –40°C to +125°C temperature range.