SAA7712H

1.1 Hardware features

` Digital Signal Processor (DSP) core:
   18 bits data width, 12 bits coefficient width
   Separate X, Y and P memories (both 384 bytes word XRAM and YRAM, 3 kbytes word PROM)
   1 kbytes delay line memory suited for Dolby Pro Logic Surround.
` Inputs:
   2 slave 18-bit digital stereo inputs: I²S-bus and LSB-justified serial formats
   2 master 18-bit digital stereo inputs: I2S-bus and LSB-justified serial formats.
` Outputs:
   4 DACs with 4-times oversampling and noise shaping, fed to 4 output pins and configurable from the DSP program, as left, right, front and surround channels of a Dolby Pro Logic Surround system
   2 master 18-bit digital stereo outputs: I2S-bus and LSB-justified serial formats.
` 4-channel 5-band or 2-channel 10-band I²C-bus controlled parametric equalizer
` I<sup>2</sup>C-bus microcontroller interface for:
   Access to full X and Y memory space
   Control of hardware settings: selectors, programmable clock generations, etc.
` Controllable Phase-Locked Loop (PLL) to generate the high frequency DSP clock from common fundamental oscillator crystal
` 3.3 V process with 3.3 or 5 V digital periphery:
3.3 or 5 V I<sup>2</sup>S-bus and I2C-bus microcontroller interfacing.
` Operating temperature range from 0 to 70 °C.

1.2 Software features

` Dolby Pro Logic Surround/Dolby 3 stereo: Trademark of Dolby Laboratories Licensing Corporation
` Noise generation: A pink noise generator is included for installation of the Dolby Pro Logic/Dolby 3 stereo mode
` Hall/Matrix Surround: When no Dolby Pro Logic Surround source material is available then this mode can be used to produce a signal in the surround channel
` Incredible Surround (222-IS): This algorithm expands the stereo width (stereo expander). This is intended to be used when the 2 speakers are placed close together (TV set and Midi set).
` Robust Incredible Surround (222-RIS): Same as incredible surround only an alternative algorithm
` 3D Surround (422) or Incredible Virtual Surround: Dolby Pro Logic Surround reproduced by 2 speakers (L and R)
` IS-3D Surround (422-IS): Same as 3D Surround (422) only with extra stereo width expander on left and right
` RIS-3D Surround (422-RIS): Same as IS-3D Surround (422) with alternative algorithm
` 3D Surround (423) or Incredible Virtual Surround: Dolby Pro Logic Surround reproduced by 3 speakers (L, C and R)
` IS-3D Surround (423-IS): Same as 3D Surround (423) only with extra stereo width expander on left and right
` RIS-3D Surround (423-RIS): Same as IS-3D Surround (423-IS) with alternative algorithm
` 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.

Notes
1. Human body model: equivalent to discharging a 100 pF capacitor through a 1.5 k resistor.
2. Machine model: equivalent to discharging a 200 pF capacitor through a 2.5 H inductance and a 0 series resistor.

The SAA7712H provides for digital signal processing power in TV systems and home theatre systems.

A DSP SAA7712H 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 SAA7712H 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 of SAA7712H 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 of SAA7712H 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 of SAA7712H 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.