TEA6321T/V1,518

Overview

The TEA6321T/V1,518 is an I2C-bus controlled stereo preamplifier designed for car radio and hi-fi sound applications. It integrates a source selector for four stereo and one mono input, volume control with loudness compensation, bass and treble equalization, balance, and fader functions. The device operates on a supply voltage of 7.5V to 9.5V, drawing a typical supply current of 26 mA. Key electrical specifications include a maximum voltage gain of +20 dB, a signal-plus-noise to noise ratio of 105 dB, and channel separation of 96 dB. It features fast mute capabilities via I2C or hardware pin, ensuring clean audio transitions.

Feature Summary

• Integrated I2C-bus control for all functions including volume, balance, fader, and source selection.
• Automatic loudness characteristic control linked to volume settings for improved low-level audio fidelity.
• External interface capability for connecting noise reduction circuits or external equalizers via dedicated pins.
• Triple mute modes: zero-crossing detection, fast I2C mute, and immediate hardware mute via the MUTE pin.

Applications

• Car radio and automotive audio systems
• Hi-fi stereo preamplifiers
• Audio systems requiring integrated source switching and tone control

Procurement Notes

Verify the package type against the specific ordering suffix. The local source indicates Tape & Reel (TR) packaging for this SKU, whereas standard datasheets often reference Tube packaging for the SO32 variant. Confirm the manufacturer designation as NXP USA Inc. or its predecessor Philips Semiconductors to ensure component authenticity and traceability.

Selection Notes

Select this component for designs requiring a single-chip solution for stereo pre-amplification and tone management. Ensure the power supply provides a stable 8.5V nominal voltage within the 7.5V to 9.5V range. Designers must account for external components required for bass/treble filtering and loudness boost characteristics, as these are determined by capacitors connected to specific control pins.

Part Context

This part belongs to the TEA6321 family of sound fader control circuits originally developed by Philips Semiconductors. It serves as a specialized audio IC within the broader category of preamplifiers and audio processors. The device is distinct from general-purpose operational amplifiers due to its embedded digital logic and I2C interface tailored for consumer audio applications.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Due to the specific integration of I2C-controlled analog audio routing and loudness algorithms, direct pin-to-pin replacements may require significant schematic redesigns.

FAQ

How does the loudness control function interact with the volume setting?

The loudness filter characteristic increases automatically as the Volume I setting decreases from +20 dB down to -12 dB. At settings below -12 dB, the filter characteristic remains constant, providing maximum bass and treble boost at lower listening volumes.

What are the available mute modes for the TEA6321?

The device supports three mute modes: Zero Crossing Mode (ZCM) which delays muting until the audio signal crosses zero to prevent pops; Fast Mute via I2C bus; and Hardware Mute via the MUTE pin, which immediately mutes outputs when grounded.

Can the TEA6321 interface with external audio processing equipment?

Yes. Pins 8/23 and 10/25 allow interfacing with external noise reduction circuits. Additionally, pins B2L/B2R and TL/TR can be configured to connect an external equalizer by disabling the internal bass and treble filters via I2C commands.