ADS1220IRVAR - 24-Bit 2kSPS Delta-Sigma ADC with PGA | TI
MPN: ADS1220IRVAR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.63 | $1.63 |
| 10 | $1.47 | $14.70 |
| 100 | $1.32 | $132.00 |
| 500 | $1.18 | $590.00 |
| 1,000 | $1.05 | $1,050.00 |
Drop-in alternatives for ADS1220IRVAR β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ADS1220IRVAT
β Drop-Inπ Reference alternative (not in catalog)
ADS1120IRVAR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ADS1220IRVAR Maximum Ratings & Electrical Characteristics
| Resolution | 24 bit |
| Sample Rate | 2 kSPS (max) |
| Number of Input Channels | 4 (single-ended) / 2 (differential) |
| Converter Type | Delta-Sigma (Sigma-Delta) |
| Input Type | Differential / Single-ended via MUX |
| PGA Gain | 1 to 128 (programmable) |
| Excitation Current Sources | 2 IDACs, programmable up to 1.5 mA |
| Integrated Reference | Yes (VREF, 2.048 V) |
| Interface | SPI-compatible serial |
| Operating Temperature | -40C to +125C (I grade) |
| Package | 16-VQFN (3.5 mm x 3.5 mm), RV suffix |
| Mounting Type | Surface Mount |
| Features | PGA, VREF, 2x IDACs, burnout current source |
| Typical Applications | RTD, thermocouple, bridge sensors, portable instruments |
ADS1220IRVAR Pin Configuration
| Pin 1 | AIN0 β Analog input 0 |
| Pin 2 | AIN1 β Analog input 1 |
| Pin 3 | AIN2/REFP1 β Analog input 2 / alternate positive reference input 1 |
| Pin 4 | AIN3/REFN1 β Analog input 3 / alternate negative reference input 1 |
| Pin 5 | AVSS β Analog negative supply / ground |
| Pin 6 | AVDD β Analog positive supply |
| Pin 7 | GND β Ground reference |
| Pin 8 | DVDD β Digital supply |
| Pin 9 | SCLK β SPI serial clock input |
| Pin 10 | CS β SPI chip select (active low) |
| Pin 11 | DOUT/DRDY β SPI serial data output / data ready indicator |
| Pin 12 | DIN β SPI serial data input |
| Pin 13 | DRDY β Data ready output (new conversion available) |
| Pin 14 | RESET β Device reset input |
| Pin 15 | REFP0 β External reference positive input |
| Pin 16 | REFN0 β External reference negative input |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
ADS1220IRVAR is suitable for 6 applications: RTD Temperature Measurement, Thermocouple Input Modules, Load Cell and Bridge Sensor Digitization, Portable and Battery-Powered Instruments, Battery Management and Monitoring, Factory Automation and Process Control I/O.
RTD Temperature Measurement
The ADS1220IRVAR fits ratiometric 2-, 3-, and 4-wire RTD systems because its two matched IDACs provide sensor excitation while its PGA (gains 1-128) amplifies the small differential RTD voltage. In a typical PT100 design, a 1 mA IDAC across a 2.048 V internal reference supports ratiometric measurement in which reference drift cancels entirely, and the 24-bit resolution at 20 SPS yields sub-0.1C temperature resolution. The second IDAC enables 3-wire lead compensation, and the burnout current source detects broken sensor wires. Place the device between the RTD network and an MCU SPI bus; unlike discrete front ends, it removes separate reference, PGA, and excitation circuitry.
Recommended
Thermocouple Input Modules
Thermocouples generate tens of microvolts per degree C, demanding a low-noise, high-gain front end; the ADS1220IRVAR answers this with PGA gain up to 128 and a chopper-stabilized signal path. Its digital filter provides simultaneous 50 Hz and 60 Hz line-noise rejection, critical for industrial modules operating near mains-powered equipment. The integrated burnout current source detects open or shorted thermocouple junctions, enabling fault alarms required by process-control standards, and the IDACs can excite a cold-junction compensation sensor on a spare channel. At the lowest data rate, effective resolution approaches 30 bits, giving K-type thermocouple systems sub-0.1C resolution without external precision amplifiers.
Recommended
Load Cell and Bridge Sensor Digitization
Bridge sensors such as load cells and pressure transducers produce full-scale outputs of only a few millivolts per volt of excitation, so the ADS1220IRVAR's low-noise PGA and 24-bit converter are a strong match. By measuring the bridge ratiometrically against the excitation voltage applied to the reference inputs, supply-drift errors cancel, and the PGA gain of 128 scales a 2 mV/V load cell to the converter's input range. The two IDACs can also support half-bridge or current-excited bridge topologies. In weigh-scale and pressure-transmitter designs, one ADS1220 replaces a discrete instrumentation amplifier, reference, and ADC, cutting BOM count and calibration effort.
Recommended
Portable and Battery-Powered Instruments
The ADS1220IRVAR is explicitly positioned by TI as a low-power device, and its complete integration (PGA, reference, IDACs, SPI ADC) in a 3.5x3.5 mm VQFN makes it ideal for handheld meters, dataloggers, and battery analyzers where board area and energy budget are tight. Duty-cycled operation is straightforward: place the device in shutdown between conversions via the SPI power-down command and wake it on demand, so average current scales with the measurement schedule. The wide operating temperature range of -40C to +125C covers outdoor and industrial handheld use. Compared with a discrete analog front end, the single-chip solution also reduces quiescent budget and simplifies firmware development.
Recommended
Battery Management and Monitoring
Battery pack supervisory circuits benefit from the ADS1220IRVAR's four multiplexed inputs, which can monitor cell voltages, pack current via a shunt, and temperature in one device. The PGA gain settings let a single converter resolve both millivolt-level shunt signals and larger cell-level voltages, while the IDACs can bias NTC thermistors used for pack temperature sensing. The SPI interface with DRDY handshake integrates cleanly with battery-management MCUs, and the device's precision supports coulomb-counting accuracy improvements when paired with low-value shunts. For higher channel-count packs, TI's ADS131M08 extends the same delta-sigma approach to eight simultaneous channels.
Recommended
Factory Automation and Process Control I/O
Analog input modules in PLCs and distributed control systems need multiple sensor types on one converter: the ADS1220IRVAR's flexible MUX accepts RTDs, thermocouples, and millivolt signals, while its 50/60 Hz rejection maintains accuracy in electrically noisy cabinets. The CRC-capable SPI interface adds communication robustness for module backplanes, and the -40C to +125C industrial temperature grade suits DIN-rail hardware. Ratiometric reference operation keeps calibration stable across production tolerance of the excitation source. System designers often pair the converter with an MCU running linearization firmware, replacing multi-chip analog front ends and reducing module size, cost, and per-channel calibration time.
Recommended
Recommended Products Summary
Engineering reference data for ADS1220IRVAR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADS1220IRVAT | ADS1120IRVAR |
|---|---|---|---|
| Package | 16-VQFN (3.5x3.5 mm) | 16-VQFN (3.5x3.5 mm) - same | 16-VQFN (3.5x3.5 mm) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Resolution | 24 bit | 24 bit | 16 bit |
| Sample Rate | 2 kSPS | 2 kSPS | 2 kSPS |
| Input Channels | 4 SE / 2 diff | 4 SE / 2 diff | 4 SE / 2 diff |
| PGA Gain Range | 1 to 128 | 1 to 128 | 1 to 128 |
| IDACs | 2 programmable | 2 programmable | 2 programmable |
| Interface | SPI | SPI | SPI |
| Packing | Partial reel (RVAR) | Full tape and reel | Partial reel |
Key Differentiators
- Full 24-bit resolution with integrated PGA (vs ADS1120IRVAR)
- Highly integrated sensor front end (vs ADS1220IRVAT (same die))
- Broad second-source scarcity is a supply risk (vs ADS1120IRVAR)
Design Notes
Place 1 uF ceramic decoupling capacitors directly at AVDD (pin 6) and DVDD (pin 8) with short, low-inductance returns to the AVSS/GND plane. Keep the analog input routing (AIN0-AIN3) away from the SPI clock and data lines to prevent digital coupling into the 24-bit converter; even picofarad-level coupling can produce visible LSB chatter at low data rates. Use a solid ground plane and, for ratiometric RTD designs, run IDAC and reference resistor currents with Kelvin connections to REFP0/REFN0.
Use the DRDY pin (or the DOUT/DRDY shared function) to time SPI reads rather than polling blindly; reading during a conversion update can corrupt the output word. Enable the optional CRC data-integrity feature on the SPI bus for industrial environments with high EMI, and keep SCLK edge rates moderate - excessive ringing on clock lines at 4-wire interfaces commonly manifests as intermittent communication faults rather than subtle errors.
Watch IDAC self-heating in RTD designs: a 1 mA excitation through a 100-ohm PT100 dissipates only about 0.1 mW in the sensor, but higher IDAC settings on low-resistance RTDs can raise sensor temperature and bias readings - estimate the self-heating error from the RTD dissipation constant before fixing the excitation current. Also do not exceed the datasheet absolute maximum input ratings on AIN pins when the sensor sits at a different common-mode potential than AVSS.
Compliance Information
Compliance certificates are published per orderable part number on the TI product page under ordering and quality information; verify on ti.com/product/ADS1220 as of 2026-09-03.
