ADS1222IPWT

Overview

The ADS1222IPWT is a 24-bit delta-sigma analog-to-digital converter (ADC) manufactured by Texas Instruments. It features two differential input channels with an integrated multiplexer and supports data rates up to 240 SPS using a 4 MHz clock. The device operates on a single supply voltage ranging from 2.7 V to 5.5 V for both analog and digital domains, consuming typically 300 µA of analog supply current. It utilizes a simple 2-wire serial interface compatible with I2C and SPI protocols. Key performance metrics include a maximum integral nonlinearity (INL) of 0.0015% FSR and a differential nonlinearity (DNL) of ±1 LSB. The component is housed in a TSSOP-14 package and functions within a temperature range of -40°C to +85°C.

Feature Summary

• Integrated 2-channel differential input multiplexer with pin-selectable high-impedance input buffer
• On-chip self-calibrating circuitry and internal temperature sensor
• Supports 50 Hz and 60 Hz line frequency rejection capabilities
• Low power consumption with single conversion and standby mode functionality

Applications

• Battery-powered portable instrumentation systems
• Industrial process control and monitoring
• Medical equipment requiring high-resolution signal acquisition
• Weight scales and load cell interfaces

Procurement Notes

Verify the specific suffix 'WT' against the manufacturer's official documentation to confirm packaging details, as it denotes tape and reel delivery compared to the 'WR' variant. Ensure compatibility with required operating temperatures and interface protocols before integration. Cross-reference the datasheet revision date to confirm current manufacturing status and any potential design changes affecting pinout or electrical characteristics.

Selection Notes

Select this component when high resolution and low noise are critical for differential signal sources. The built-in multiplexer simplifies board layout for multi-channel applications. Consider the external reference requirement and the need for a 4 MHz clock source for optimal performance at higher data rates. Evaluate power budget constraints given the low quiescent current specifications.

Part Context

This part belongs to the ADS122x family of precision ADCs from Texas Instruments. It shares architectural similarities with the ADS1220 and ADS1221 but offers enhanced channel count and specific input buffering options. The IPW suffix indicates a plastic TSSOP package with industrial temperature rating, distinguishing it from broader commercial or automotive variants within the same product line.

Replacement Considerations

The ADS1222IPWR is a direct functional equivalent differing primarily in packaging format (reel vs. cut tape). Other members of the ADS122x series may serve as alternatives if channel count or data rate requirements differ. Verify pin compatibility and software register settings when substituting with related devices.

FAQ

What is the maximum differential input voltage range?

The ADS1222 supports a differential input range of ±5 V.

Does the device require an external reference voltage?

Yes, the ADS1222 requires an external reference voltage; it does not contain an internal reference.

How is the input buffer configured?

The high-impedance input buffer is pin-selectable, allowing users to enable or disable it based on application needs.