TC94A04AF/AFD is a single-chip audio Digital Signal Processor, incorporating 4 way stereo analog switch, 2 ch AD converter, 4 ch DA converter, and electronic volume for trimming.
It is possible to realize many applications, such as sound field control -hall simulation, for example-, digital filter for equalizers, surround, base boost and something.

Features
• Incorporates a 4 ch-stereo analog switch for AD converter input.
• Incorporates a 1 ch stereo line-out.
• Incorporates a 1 bit ∑ ∆-type AD converter (two channels).
   THD: −82dB (typ.) S/N: 95dB (typ.)
• Incorporates a 1 bit ∑ ∆-type DA converter (four channels).
   THD: −86dB (typ.) S/N: 98dB (typ.)
• Incorporates a trimming analog volume for each output of DA converter. 0dB to −24dB (1dB step)
• As digital input/output port, this has 3 input port (6 ch) and 1 output port (2 ch), enabling input/output of sampling of 96 kHz/24 bit.
• Incorporates a built-in digital de-emphasis filter.
• Incorporates a digital attenuator.
• Incorporates a boot ROM to set a coefficient automatically, which enables to transfer an initial data from built-in ROM/RAM to registers at the time of resetting Boot ROM: 512 words
• The DSP block specifications are as follows:
   Data bus: 24 bits
   Multiplier/adder: 24 bits × 16 bits + 43 bits → 43 bits
   Accumulator: 43 bits (sign extension: 4 bits)
   Program ROM: 1024 words × 32 bits
   Coefficient RAM: 384 words × 16 bits
   Coefficient ROM: 256 words × 16 bits
   Offset RAM: 16 words × 11 bits
   Data RAM: 256 words × 24 bits
   Interface buffer RAM: 32 words × 16 bits
   Operation speed: 22.5 MIPS (510 step/fs: master clock = 768 fs, fs = 44.1 kHz)
   Note 1: At the time of an analog input, approximately 170 steps (85 step/ch) in 510 step are used for the operation of the decimation filter for AD converters.
• Incorporates data delay RAM (32 kbits).
   Delay RAM: 2048 words × 16 bits (32 kbits)
• The microcontroller interface can be selected between Toshiba original 3 line mode and I2C mode.
• CMOS silicon structure supports high speed.
• Power supply is a single 5 V.
• The package are 60-pin and 80 pin flat package.