ADAU1977WBCPZ-RL

Overview

The ADAU1977WBCPZ-RL is a quad analog-to-digital converter (ADC) with integrated diagnostics, designed for automotive audio applications. It features four direct-coupled differential inputs capable of handling 10 V rms line-level signals or connecting directly to electret microphones via a programmable 5 V to 9 V bias. The device utilizes a multibit sigma-delta architecture with a continuous-time front end for low EMI. Key specifications include a 24-bit resolution, 109 dB dynamic range, and -95 dB THD+N. It operates on a single 3.3 V supply, incorporates an on-chip PLL for clock generation, and supports I2C/SPI control interfaces.

Feature Summary

• Quad ADC with 24-bit resolution, 109 dB dynamic range, and -95 dB THD+N
• Integrated microphone bias generator (5 V to 9 V) with comprehensive fault detection
• On-chip PLL for master clock derivation from external clock or frame clock
• Supports Right Justified, Left Justified, I2S, and TDM serial data formats

Applications

• Automotive audio systems
• Active noise cancellation systems

Procurement Notes

Verify the Rev. D datasheet specifications against the specific manufacturing lot. Confirm that the LFCSP-40 package thermal requirements are met in the target design. Ensure the ordering suffix matches the required reel quantity and packaging format for automated assembly processes.

Selection Notes

Select this component when high-fidelity multi-channel audio digitization is required alongside built-in sensor diagnostics. The integrated boost converter simplifies power management for microphone arrays. Verify compatibility with the system's digital interface standards, specifically regarding I2C address configuration and SPI timing constraints.

Part Context

This part belongs to the ADAU1977 family of audio interface devices. It is distinct from other Analog Devices codecs by its focus on input-side diagnostics and direct microphone connectivity without external preamplifiers. The WBCPZ suffix indicates the automotive-grade qualification and LFCSP-40 packaging.

Replacement Considerations

Direct pin-compatible replacements within the same diagnostic-focused quad ADC family should be evaluated based on updated revision specifications. Cross-family substitution requires careful verification of register maps and electrical characteristics.

FAQ

How does the ADAU1977 handle microphone bias?

It includes an internal DC-to-DC boost converter that generates a programmable microphone bias voltage ranging from 5 V to 9 V, eliminating the need for external bias circuits.

What diagnostic faults can the device detect?

The device detects short to battery, short to microphone bias, short to ground, short between positive and negative input pins, and open input terminals, reporting them via an IRQ flag.

What is the maximum differential input voltage?

The full-scale differential input voltage is 10 V rms for line input applications, allowing direct connection to high-level audio sources.