AD7730BRU

Overview

The AD7730BRU is a 24-bit Sigma-Delta analog-to-digital converter (ADC) designed for weigh scale and pressure measurement applications. It features two buffered differential programmable gain inputs, an on-chip 6-bit DAC for offset removal, and a serial interface compatible with microcontrollers. The device operates from a single +5 V supply with digital logic supporting 2.7 V to 5.25 V. Key performance metrics include a peak-to-peak resolution of 230,000 counts, integral nonlinearity of 18 ppm FSR, and offset drift of 5 nV/°C. It is housed in a 24-lead TSSOP package.

Feature Summary

• 24-bit resolution with no missing codes and 230,000 peak-to-peak counts
• Two-channel programmable gain front end with input ranges from ±10 mV to ±80 mV
• On-chip 6-bit DAC for tare voltage removal and AC excitation clock outputs
• Serial interface configurable for three-wire operation

Applications

• Weigh scales
• Pressure measurement

Procurement Notes

Verify the suffix 'RU' corresponds to the 24-lead TSSOP package and industrial temperature range (-40°C to +85°C). Confirm that the specific revision matches the required electrical specifications, as parameters may vary between versions. Ensure compatibility with the intended power supply voltages (AVDD = 5 V, DVDD = 2.7 V to 5.25 V).

Selection Notes

Select this component when high precision is required for low-level transducer signals. The integrated PGA eliminates the need for external amplifiers for bridge sensors. Consider the on-chip DAC if tare functionality is needed without external circuitry. Verify that the available update rates and filter settings meet the system's dynamic response requirements.

Part Context

The AD7730 is part of Analog Devices' family of complete analog front ends for transducer applications. It integrates the modulator, programmable gain amplifier, digital filter, and reference detection into a single chip. This integration reduces board space and simplifies the design of high-resolution measurement systems compared to discrete solutions.

Replacement Considerations

Publicly confirmed substitute part numbers are not provided in the source material.