TLC320AD81C Datasheet, PDF (9/47 Pages) Texas Instruments – Stereo Audio Digital Equalizer DC

1 Introduction
The TLC320AD81C performs standard audio signal processing for bass, treble, and volume, as well as
parametric equalization on a digital audio stream resulting in superior quality audio normally not available
in a low-cost solution. The TLC320AD81C contains a digital audio processor, a slave I²C interface port, and
a sigma-delta digital-to-analog converter (DAC). The audio control functions (volume, treble, and bass,) and
parametric EQ coefficients are downloaded through the I²C port to the TLC320AD81C.
The volume, treble, and bass controls may be dynamically adjusted by the user. They are updated within
the device without degradation of the output signal.
The parametric EQ consists of multiple cascaded independent biquad filters per channel. Each biquad has
five 24-bit coefficients that can be downloaded across the I²C port. The parametric EQ should not be
updated while digital audio data is being processed, because the update will possibly cause audible
artifacts.
The digital audio processor and on-chip logic use an internal system clock that is generated by the PLL from
the system clock provided to the device at the master clock input.
The TLC320AD81C supports three audio serial interface formats (I²S, left justified, and right justified) with
data word lengths of 16, 18, and 20 bits (16-bit, 32 f_s mode is only supported by left justified). The sampling
frequency may be set to 44.1 kHz or 48 kHz. An I²C slave port is used to download filter coefficients and
control information to the TLC320AD81C.
Additionally, two address-select pins allow multiple TLC320AD81Cs to be cascaded on the I²C bus to
support left, right, and sub (3-channel) systems or left, right, center, rear left, rear right, and sub (6-channel)
systems.
The sigma-delta DAC has 64x oversampling. Typically, the DAC also has a 98-dB signal-to-noise ratio
(SNR) and a 94-dB dynamic range at 5 V. Hardware control for de-emphasis is supported for CD
applications at 44.1 kHz. Hardware control for soft mute is also provided.
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