AD1974WBSTZ

Overview

The AD1974WBSTZ is a high-performance, single-chip analog-to-digital converter (ADC) featuring four differential inputs utilizing a multibit sigma-delta architecture. It operates on a single 3.3 V supply and supports sample rates from 8 kHz to 192 kHz with 24-bit resolution. Key electrical specifications include a dynamic range of 107 dB and total harmonic distortion plus noise (THD+N) of -94 dB. The device integrates an on-chip phase-locked loop (PLL) for clock generation, reducing electromagnetic interference (EMI). It offers flexible digital interfaces including I2S, left/right justified, and TDM modes, housed in a 48-lead LQFP package.

Feature Summary

• Four-channel 24-bit ADC with differential inputs and 107 dB dynamic range
• Integrated PLL generates master clock from LRCLK or external crystal
• Low EMI design optimized for automotive and consumer audio applications
• Supports I2S, Left/Right Justified, and TDM serial data formats

Applications

• Automotive audio systems
• Home theater systems
• Set-top boxes
• Digital audio effects processors

Procurement Notes

Verify the specific suffix 'W' indicates automotive qualification status as per the manufacturer's ordering guide. Confirm that the LQFP package dimensions match the target PCB footprint requirements. Ensure power supply decoupling capacitors are placed close to AVDD and DVDD pins to maintain signal integrity and meet EMI specifications.

Selection Notes

Select this component when a low-power, high-resolution ADC with integrated clocking is required. The on-chip PLL eliminates the need for external high-frequency oscillators, simplifying board layout. Verify that the system can accommodate the 3.3 V logic levels and that the SPI control interface is available for configuration. Consider thermal resistance characteristics if operating at maximum sample rates.

Part Context

The AD1974 is part of Analog Devices' audio data converter portfolio, designed specifically for multi-channel audio processing. It serves as a direct replacement for legacy stereo ADCs in systems requiring expansion to quadraphonic or surround sound channels without increasing component count significantly.

Replacement Considerations

Publicly confirmed substitute part numbers are not provided in the source documentation. Cross-referencing should be performed based on pin compatibility and electrical specifications such as dynamic range and supply voltage.

FAQ

How is the master clock generated?

The master clock can be generated by the on-chip PLL using the LRCLK or an external crystal, or it can be provided directly via the MCLKI pin.

What is the input common-mode voltage?

The differential inputs have a nominal common-mode voltage of 1.5 V, which can be biased using the CM pin.

Can the device operate in standalone mode?

Yes, standalone mode is available by grounding CIN, CCLK, and CLATCH, configuring the device with default settings and I2S format.