ADS1261 24-Bit 40 kSPS 10-Ch Delta-Sigma ADC

By Texas Instruments 117

ADS1261 24-Bit 40 kSPS 10-Ch Delta-Sigma ADC

Texas Instruments' ADS1261 is a precision, 40 kSPS, delta-sigma (ΔΣ) analog-to-digital converter (ADC) with an integrated programmable gain amplifier (PGA) and internal fault monitors. The sensor-ready ADC provides a high-accuracy, single-chip solution for the most demanding measurements, including weigh scales and resistance temperature devices (RTD).

The ADC is comprised of an input signal multiplexer, a low-noise PGA, providing gain from 1 to 128, a 24-bit ΔΣ modulator, and a programmable digital filter.

The high-impedance PGA inputs (1 GΩ) reduce measurement error caused by sensor loading. 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 single-cycle settled conversions while providing simultaneous 50 Hz and 60 Hz line cycle rejection. Signal and reference monitors, a temperature sensor, and CRC data verification enhance data reliability.

The ADS1261 is a pin-compatible device offered in a 5 mm x 5 mm QFN package and is specified over the -40°C to +125°C temperature range.

  • 24-bit, high-precision ADC
    • 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
  • 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
  • Excitation current sources
  • Sensor burn-out current sources
  • Four general-purpose input/outputs
  • AC excitation for bridge sensors
  • 5 mm x 5 mm QFN package
  • PLC analog input modules
  • Weigh scales and strain-gauge digitizers
  • Temperature, pressure measurement
  • Lab instrumentation
  • Process analytics