SAA7712H Datasheet, PDF (4/44 Pages) NXP Semiconductors – Sound effects DSP

Philips Semiconductors
Sound effects DSP
Preliminary specification
SAA7712H
• Voice cancelling (karaoke): Rejects voice out of
source material, mainly intended to be used with
karaoke. Several karaoke modes available in stereo
mode and in Dolby Pro Logic mode, such as (auto) voice
cancel, (auto) centre voice cancel, (auto) multi left and
(auto) multi right.
• Microphone mix modes (karaoke): Mono microphone
mixed to left, right and centre channel
• Spectrum analysis: 3-band spectrum analyser is
provided
• Dolby B: Both a Dolby B encoder as well as a Dolby B
decoder is implemented
• 2 Room solution: In all modes not requiring more than
2 output channels (stereo and karaoke incredible
surround) it is also possible to feed the source signal to
the other 2 output channels (with same processed or
not processed signal)
• Dynamic Bass Enhancement (DBE): Dynamic bass
enhancement generates a sub-woofer channel, which is
either a separate output or is added to the front channels
• Volume processing: Independent volume processing
of all 4 output channels
• AC-3/MPEG-2: Inputs available intended to be used
with an AC-3/MPEG-2 co-processor. In this mode the
SAA7712H can be used as post-processor.
• Output redirection: Several output configurations are
possible (normal 4 channel, special 4 + 2 channel,
record 2 + 2 channel, 6 or 6 + 2 channel).
Depending on the sample frequency several combinations
of the above mentioned features are possible.
3 GENERAL DESCRIPTION
The SAA7712H provides for digital signal processing
power in TV systems and home theatre systems.
A DSP core is equipped with digital inputs and outputs, a
5-band parametric equalizer accelerator, a digital
co-processor interface and a delay line memory. This
architecture accommodates on-chip standard sound
processing, incredible surround, Dolby Pro Logic Surround
and other surround sound processing algorithms.
The architecture also supports co-processing, e.g. to add
to the processing power of the internal DSP core or for
multi-channel surround decoding.
All settings and parameters are controlled by an I²C-bus
interface. The available interfaces support a high
application flexibility.
The DSP core communicates over 32 dedicated registers.
The selected digital input is master for the data rate of the
DSP core. This input can be selected among 2 slave
I²S-bus inputs. The 4 outputs from the core are passed
through 4 DACs and then routed to 4 output pins.
Two master I²S-bus outputs and two master I²S-bus
inputs can serve as an I²S-bus co-processor interface.
Eight of the remaining registers are used for
communication with the hardware equalizer, and eight for
communication with the delay line memory.
All I²S-bus inputs and outputs support the Philips I²S-bus
format as well as 16, 18 and 20-bit LSB-justified formats.
2 APPLICATIONS
The SAA7712H can be used in TV sets with:
• Dolby Pro Logic Surround, incredible surround,
3D Surround and advanced acoustics processing
• Multi-channel sound decoding (AC-3 and MPEG-2) on a
co-processor. The SAA7712H can be used for
post-processing.
1999 Aug 05
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