ADS7128IRTER

Analog To Digital Converters (ADC) Overview

The ADS7128IRTER is an 8-channel, multiplexed, 12-bit successive approximation register (SAR) analog-to-digital converter manufactured by Texas Instruments. It features a small 3-mm × 3-mm WQFN-16 package and supports I2C communication up to 3.4 MHz with configurable addresses. The device operates on AVDD from 2.35 V to 5.5 V and DVDD from 1.65 V to 5.5 V across a -40°C to +85°C temperature range. Key specifications include a typical SNR of 73 dB at 5 V supply, 12 pF sampling capacitance, and ±0.5 LSB integral nonlinearity. It integrates internal oscillators, programmable averaging filters, and dedicated modules for RMS calculation and zero-crossing detection.

Analog To Digital Converters (ADC) Feature Summary

• Eight channels independently configurable as analog inputs or general-purpose digital I/Os
• Integrated digital window comparator with programmable thresholds and event counters for analog watchdog functions
• Built-in root-mean-square module providing 16-bit true RMS results for any analog input channel
• Zero-crossing-detect module with built-in transient rejection and digitally adjustable hysteresis

Analog To Digital Converters (ADC) Applications

• Mobile robot CPU boards
• Refrigerators and freezers
• Digital multimeters (DMM)
• Rack servers

Analog To Digital Converters (ADC) Procurement Notes

Verify the specific ordering suffix against the manufacturer's current orderable addendum to confirm package type and reel specifications. Ensure that the required I2C address configuration resistors are included in the design, as the ADDR pin determines the device address upon power-up. Confirm that the host system supports the desired I2C clock speed mode, ranging from standard to high-speed.

Analog To Digital Converters (ADC) Selection Notes

Select this component when an 8-channel multiplexed ADC with GPIO flexibility is required in a compact footprint. It is suitable for applications needing integrated signal processing features like RMS computation and zero-crossing detection without external microcontroller overhead. Consider the AVDD reference requirement and ensure the source impedance of analog inputs is compatible with the 12 pF sampling capacitor for accurate acquisition.

Analog To Digital Converters (ADC) Part Context

The ADS7128 belongs to the ADS71xx family of small, multi-channel SAR ADCs. Unlike the ADS7138, which lacks advanced signal processing blocks, the ADS7128 includes CRC verification, RMS calculation, and zero-crossing detection capabilities. It shares the same 16-pin WQFN package form factor but offers enhanced functionality for complex monitoring tasks compared to basic conversion-only devices in the series.

Analog To Digital Converters (ADC) Replacement Considerations

The ADS7138 serves as a functional substitute if CRC, RMS, and ZCD modules are not required. For SPI interface requirements, consider the ADS7038 or ADS7028 families. Verify pin compatibility and software register mapping differences when migrating between these variants.