The AK7770 audio DSP for DTV sound processing from Asahi Kasei EMD Corporation integrates two 24-bit stereo ADCs, three 24-bit stereo DACs and two stereo SRCs, as well as an S/PDIF transmitter. A four-channel stereo line-input selector allows different sound sources to be selected for the main screen speaker outputs or a sub screen headphone output.
The SRCs allow for operation at a 48-kHz sampling rate with input rates of 32, 44.1, or 48 kHz, and can support two different sampling rate frequency signals for two screens. Volume control, compression, EQ and sound processing are performed by the DSP. A delay adjustment up to 70 ms is possible for four output channels through integrated delay RAM.
14k-words of delay memory are available for surround-sound effects and lip-synching. In addition, the RAM program area is freely programmable for user applications. For SRS licensed users, programs such as WOW HD can be provided. Users can create their own applications by combining the standard program with the original algorithm.
Specifications include a dynamic range of 96 dB for the ADC and 100 dB for the DAC. Operating voltage ranges from 1.7 V to 1.9 V for the digital block and 2.7 V to 3.6 V for the analog and interface blocks.
The AK7770 is packaged in an 80-pin LQFP. Evaluation boards and samples are available now.
AKM Semiconductor , 408-436-8580, http://www.akm.com/
AK7770 datasheet (PDF)