The DADS1220/DADS1120 is a precision 24/16-bit analog-to-digital converter (ADC) that integrates features to reduce system cost and component count in small sensor signal measurement applications. The device features two differential inputs or four single-ended inputs via an input multiplexer (MUX), a low-noise programmable gain amplifier (PGA), two programmable drive current sources, a voltage reference, an oscillator, a low-side switch, and a precision temperature sensor.

This device can perform conversions at sampling data rates up to 2000 samplings per second (SPS) and is stable within a single cycle. For industrial applications in noisy environments, the digital filter provides simultaneous 50Hz and 60Hz rejection at a sampling frequency of 20 SPS. The internal PGA provides up to 128V of gain. This PGA makes the chip ideal for small sensor signal measurement applications such as resistive temperature detectors (RTDs), thermocouples, thermistors, and resistive bridge sensors.

The device supports the measurement of pseudo-differential or fully differential signals when using the PGA. Furthermore, this device can be configured to disable the internal PGA while still providing high input impedance and up to 4VV gain, enabling single-ended measurements.

Power consumption can be as low as 120uA in duty cycle mode with the PGA disabled. The device is available in a leadless QFN16L or Thin Small Outline (TSSOP)-16 package and is rated for operation from -40°C to +125°C.

• Low current consumption: as low as 120μA (typical) in duty cycle mode.
• Wide power supply range: 2.3V to 5.5V.
• Programmable gain: 1V/V to 128V/V.
• Programmable data rate: up to 2kSPS.
• Up to 20-bit effective resolution (1220).
•         16-bit noise-free resolution (at 20 SPS) (1120).
• A single-cycle stable digital filter is used to achieve 50Hz and 60Hz harmonic suppression at 20SPS.
• Two differential inputs or four single-ended inputs.
• Dual-matched programmable current sources: 10 μA to 1.5mA (1220) / 50 μA to 1.5mA (1120).
• Integrated 2.048V reference voltage: drift 5ppm/℃ (typical).
• Integrated 2% precision oscillator.
• Integrated temperature sensor: accuracy 0.5°C (typical).
• SPI-compatible interface (Mode 1).
• Package: 4.0mm × 4.0mm × 0.85mm ultra-thin quad flat.

• Temperature sensor measurement:
•         Thermistor.
•         Thermocouple.
• Resistance temperature detector (RTD):
•         2-wire, 3-wire, or 4-wire type.
• Resistance bridge sensor measurement:
•         Pressure sensor.
•         Stress gauge.
•         Weighing instruments.
•         Portable instrument.
•         Industrial automation and process control.