AD7730LBR-REEL7

Overview

The AD7730LBR-REEL7 is a complete analog front end for weigh-scale and pressure measurement applications, manufactured by Analog Devices Inc. It accepts low-level signals directly from transducers and outputs a serial digital word. The device features two buffered differential programmable gain analog inputs and operates from a single +5 V supply. Key specifications include a peak-to-peak resolution of 230,000 counts, an offset drift of less than 5 nV/°C, and a gain drift of less than 2 ppm/°C. It supports input ranges from ±10 mV to ±80 mV and includes an on-chip 6-bit DAC for offset removal.

Feature Summary

• 24-bit Sigma-Delta ADC with 230,000 counts peak-to-peak resolution
• Two-channel programmable gain front end with buffered differential inputs
• Low drift characteristics: Offset < 5 nV/°C, Gain < 2 ppm/°C
• On-chip 6-bit DAC for TARE/offset removal

Applications

• Weigh scales
• Pressure measurement

Procurement Notes

Verify the specific 'L' variant designation against the datasheet Appendix A, as performance parameters differ from the standard AD7730. Confirm the BRU suffix indicates the TSSOP-24 package and REEL7 denotes tape-and-reel packaging. Ensure compatibility with the specified 2.4576 MHz master clock frequency required for the L version.

Selection Notes

Select this component when high precision and low drift are critical for bridge transducer applications. The AD7730L requires a 2.4576 MHz clock, distinct from the 4.9152 MHz used by the standard AD7730. Consider the CHP bit configuration; enabling chopping reduces drift significantly but may affect noise performance in skip mode.

Part Context

This part belongs to the AD7730 family of Bridge Transducer ADCs. The AD7730L is a specific variant optimized for different clocking requirements compared to the standard AD7730. Both share the same functional block diagram and pinout but have distinct electrical specifications regarding clock frequency and drift performance as detailed in the manufacturer's documentation.

Replacement Considerations

The standard AD7730 is functionally similar but requires a 4.9152 MHz clock instead of the 2.4576 MHz required by the AD7730L. Verify clock source compatibility before substitution. Other ADI ADCs like the AD7732 offer different channel counts and packages.