AD7768-4BSTZ-RL7

Overview

The AD7768-4BSTZ-RL7 is a 24-bit, 4-channel simultaneous sampling sigma-delta analog-to-digital converter (ADC) from Analog Devices. It features a maximum output data rate of 256 kSPS per channel and achieves a dynamic range of 108 dB with a maximum input bandwidth of 110.8 kHz. The device offers selectable power modes to optimize noise targets and power consumption, including fast, median, and low power options. It includes integrated digital filters such as wideband linear phase and sinc5 filters, along with CRC error checking on the data interface. The component operates within a temperature range of -40°C to +105°C and is housed in a 64-lead LQFP package.

Feature Summary

• Simultaneous sampling across four channels with independent sigma-delta modulators and digital filters for synchronized ac and dc signal acquisition.
• Configurable power scaling allows trade-offs between input bandwidth, output data rate, and power dissipation through three distinct operating modes.
• Integrated digital filtering capabilities include wideband brick-wall filters with low pass-band ripple and low-latency sinc5 filters for versatile measurement applications.

Applications

• Data acquisition systems utilizing USB, PXI, or Ethernet interfaces
• Instrumentation and industrial control loops requiring high precision
• Audio testing and measurement equipment
• Vibration and asset condition monitoring systems
• High precision medical electroencephalogram (EEG), electromyography (EMG), and electrocardiogram (ECG) devices

Procurement Notes

Verify the specific ordering suffix RL7 corresponds to the reel packaging configuration required for your assembly line. Confirm that the LQFP-64 footprint matches your PCB design guidelines. Ensure compatibility with the specified voltage levels for AVDD1, AVDD2, and IOVDD supplies before finalizing procurement orders.

Selection Notes

Select this component when simultaneous multi-channel sampling is critical for maintaining time coherence in sensor arrays. Evaluate the available decimation rates and filter types against your required input bandwidth and noise performance specifications. Consider the power dissipation characteristics of each operating mode relative to your thermal management constraints and system power budget.

Part Context

This part belongs to the AD7768 family of high-performance sigma-delta ADCs. The AD7768-4 variant specifically provides four channels, whereas the standard AD7768 offers eight channels. Both share identical core architecture, performance metrics, and pinout configurations, differing primarily in channel count and associated register maps.

Replacement Considerations

Public confirmed substitute part numbers are not provided in the source documentation. Verify functional equivalence carefully if considering alternative manufacturers, particularly regarding pin compatibility and register mapping.

FAQ

What is the maximum input bandwidth supported by the AD7768-4?

The device supports a maximum input bandwidth of 110.8 kHz at the -3 dB point when operating in fast mode with the wideband filter enabled.

How does the device handle data integrity during transmission?

The data interface supports CRC error checking to ensure data integrity. Additionally, the device allows for daisy-chaining multiple units for expanded channel counts.

Can the power consumption be optimized for lower bandwidth applications?

Yes, the device offers three selectable power modes: fast, median, and low power. Users can trade off input bandwidth and output data rate against power dissipation to meet specific noise and efficiency targets.