ADS1220 - 24-Bit, 2kSPS, 4-Ch, Low-Power Delta-Sigma ADC With PGA and VREF for Small Signal Sensors

The ADS1220 is a precision, 24-bit, analog-to-digital converter (ADC) that offers many integrated features to reduce system cost and component count in applications measuring small sensor signals. The device features two differential or four single-ended inputs through a flexible input multiplexer (MUX), a low-noise, programmable gain amplifier (PGA), two programmable excitation current sources, a voltage reference, an oscillator, a low-side switch, and a precision temperature sensor.

The device can perform conversions at data rates up to 2000 samples-per-second (SPS) with single-cycle settling. At 20 SPS, the digital filter offers simultaneous 50-Hz and 60-Hz rejection for noisy industrial applications. The internal PGA offers gains up to 128 V/V. This PGA makes the ADS1220 ideally-suited for applications measuring small sensor signals, such as resistance temperature detectors (RTDs), thermocouples, thermistors, and resistive bridge sensors. The device supports measurements of pseudo- or fully-differential signals when using the PGA. Alternatively, the device can be configured to bypass the internal PGA while still providing high input impedance and gains up to 4 V/V, allowing for single-ended measurements.

Power consumption is as low as 120 µA when operating in duty-cycle mode with the PGA disabled. The ADS1220 is offered in a leadless VQFN-16 or a TSSOP-16 package and is specified over a temperature range of –40°C to +125°C.

• Low Current Consumption:
  As Low as 120 µA (typ) in Duty-Cycle Mode
• Wide Supply Range: 2.3 V to 5.5 V
• Programmable Gain: 1 V/V to 128 V/V
• Programmable Data Rates: Up to 2 kSPS
• Up to 20-Bits Effective Resolution
• Simultaneous 50-Hz and 60-Hz Rejection at
  20 SPS with Single-Cycle Settling Digital Filter
• Two Differential or Four Single-Ended Inputs
• Dual Matched Programmable Current Sources:
  10 µA to 1.5 mA
• Internal 2.048-V Reference: 5 ppm/°C (typ) Drift
• Internal 2% Accurate Oscillator
• Internal Temperature Sensor:
  0.5°C (typ) Accuracy
• SPI-Compatible Interface (Mode 1)
• Package: 3.5-mm × 3.5-mm × 0.9-mm VQFN