AD7730BR-REEL

Overview

The AD7730BR-REEL is a complete analog front-end for weigh-scale and pressure measurement applications, manufactured by Analog Devices Inc. It features a 24-bit Sigma-Delta ADC with two buffered differential programmable gain inputs. The device operates from a single +5 V supply and accepts input ranges of ±10 mV to ±80 mV. Key specifications include an offset drift of 5 nV/°C, gain drift of 2 ppm/°C, and integral nonlinearity of 18 ppm FSR. It utilizes a 3-wire serial interface and includes an on-chip 6-bit DAC for offset removal.

Feature Summary

• 24-bit resolution with no missing codes and peak-to-peak counts of 230,000
• Two-channel programmable gain front end with input ranges from ±10 mV to ±80 mV
• Low drift characteristics: 5 nV/°C offset drift and 2 ppm/°C gain drift
• Integrated 6-bit DAC for TARE/offset removal and AC excitation control

Applications

• Weigh scales
• Pressure measurement

Procurement Notes

Verify the package type matches the specific suffix requirements, as the AD7730 series is available in 24-pin DIP, SOIC, and TSSOP packages. Confirm that the B-version industrial temperature range (-40°C to +85°C) aligns with the system design constraints. Ensure the master clock frequency is set to 4.9152 MHz for specified performance.

Selection Notes

Select this component for high-precision bridge transducer applications requiring low drift over time and temperature. The AD7730 supports both unipolar and bipolar input ranges. Consider the AD7730L if a lower master clock frequency of 2.4576 MHz is required. Verify power supply compatibility, as AVDD requires +4.75 V to +5.25 V.

Part Context

The AD7730 is part of the AD7730/AD7730L family of Bridge Transducer ADCs. It serves as a complete analog front end, integrating the PGA, modulator, digital filter, and serial interface. The BR suffix typically denotes a specific package variant within the broader AD7730 product line, often corresponding to the SOIC or TSSOP form factors depending on the manufacturer's coding.

Replacement Considerations

The AD7730L is a compatible alternative within the same family, distinguished primarily by its specified master clock frequency of 2.4576 MHz compared to the AD7730's 4.9152 MHz. Other family members like the AD7732 offer different channel counts or input ranges.