AD7716BPZ

Overview

The AD7716BPZ is a 22-bit, four-channel sigma-delta analog-to-digital converter (ADC) designed for high-precision data acquisition systems. It features on-chip low-pass digital filtering with programmable cutoff frequencies ranging from 584 Hz to 36.5 Hz. The device operates with ±5 V analog supplies and a +5 V digital supply, consuming approximately 50 mW of power. It provides a usable dynamic range of up to 111 dB at the lowest bandwidth setting. The component utilizes a five-line serial interface for control and data output, supporting both master and slave modes. It is housed in a 44-pin PLCC package and is rated for operation within a temperature range of -40°C to +85°C.

Feature Summary

• Four independent sigma-delta ADC channels enable simultaneous sampling of multiple inputs without sequential multiplexing delays.
• Integrated digital filter offers software-selectable cutoff frequencies with linear phase response to minimize signal distortion.
• Cascading capability via CASCIN and CASCOUT pins allows expansion of channel count in multi-device configurations.
• On-chip control register manages filter settings and generates auxiliary digital outputs for front-end calibration.

Applications

• Biomedical data acquisition systems such as ECG and EEG machines
• High-accuracy instrumentation requiring precise low-frequency signal measurement
• Process control applications involving chemical, physical, or biological sensors
• Seismic monitoring systems

Procurement Notes

Verify the specific ordering suffix to confirm the package type, as the AD7716 series includes both PLCC and PQFP variants. Ensure that the voltage supply requirements match the design specifications, as the device requires dual analog supplies and a separate digital supply. Confirm compatibility with the intended microcontroller interface timing for either master or slave mode operation before finalizing procurement.

Selection Notes

Select this component when high resolution and low noise are critical for low-frequency signals. The choice between master and slave mode depends on the system clock architecture. Consider the settling time associated with the selected filter bandwidth when designing for rapid channel switching, although simultaneous sampling mitigates some multiplexing constraints. Ensure external reference voltage stability to maintain specified linearity performance.

Part Context

The AD7716 belongs to Analog Devices' family of 22-bit data acquisition systems. It is part of the LC2MOS technology line, which combines low-power CMOS digital circuits with high-voltage bipolar processes. This family is specifically engineered for precision measurement applications where high resolution and low drift are required over wide temperature ranges.

Replacement Considerations

Public confirmed substitute part numbers: AD7716BS (PQFP package variant).