AD7787BRM

Overview

The AD7787BRMZ is a low-power, complete analog front end for low-frequency measurement applications. It integrates a 24-bit Sigma-Delta ADC with one differential input (AIN1) and one single-ended input (AIN2). The device operates from an internal clock, eliminating the need for external clock sources. Power supply voltage ranges from 2.5 V to 5.25 V. Normal mode current consumption is 75 µA maximum, while power-down mode draws 1 µA maximum. RMS noise is 1.1 µV at a 9.5 Hz update rate. Resolution is 19.5 bits peak-to-peak with 22 bits effective resolution. Integral nonlinearity is ±15 ppm of FSR maximum. The output data rate is software programmable from 9.5 Hz to 120 Hz. Simultaneous 50 Hz and 60 Hz rejection is provided. The device supports 3-wire serial, SPI, QSPI, Microwire, and DSP compatible interfaces.

Feature Summary

• Integrates a rail-to-rail input buffer for buffered or unbuffered operation.
• Includes a VDD monitor channel for power supply variation monitoring.
• Features simultaneous 50 Hz and 60 Hz line frequency rejection.
• Supports multiple digital interface protocols including SPI and Microwire.

Applications

• Smart transmitters
• Battery-powered applications
• Portable instrumentation
• Sensor measurement systems
• Temperature and pressure measurement

Procurement Notes

Verify the specific ordering suffix against official documentation to confirm package type and temperature range. Confirm component authenticity through authorized distribution channels. Check datasheet revision history for any updates to specifications or pin configurations prior to finalizing procurement orders.

Selection Notes

Select this component for applications requiring high-resolution, low-frequency signal acquisition with minimal power consumption. Ensure the input signal range matches the bipolar or unipolar configuration options. Verify that the required update rate aligns with the desired noise performance and rejection characteristics. Consider the MSOP-10 package constraints for PCB layout.

Part Context

The AD7787 belongs to Analog Devices' family of low-power, 24-bit Sigma-Delta ADCs designed for precision measurement. It is specifically optimized for battery-operated and portable instruments where low power consumption and high accuracy are critical. The device simplifies system design by integrating the modulator, filter, and on-chip registers into a single compact package.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided source material. Consult official manufacturer documentation for potential cross-references or updated product recommendations.

FAQ

Does the AD7787 require an external clock source?

No, the AD7787 operates with an internal clock oscillator, so no external clock source is required from the user.

What is the maximum normal mode current consumption?

The maximum normal mode current consumption is 75 µA.

Can the AD7787 measure the power supply voltage?

Yes, the device includes a VDD monitor channel that allows the ADC to measure the voltage on the power supply.