[ASAHI KASEI] [AK7746]


[MS0369-E00] - 1 - 2004/12




The AK7746 is a highly integrated audio processor, including 5 A/D channels, an input mux that can select 2 stereo pairs
from 8 stereo inputs, and an on-chip DSP. High quality analog performance is provided by the ADC’s achieving 98dB
(48kHz) dynamic range. The A/D supports sampling frequencies from 8kHz to 96kHz. The AK7746 includes 72kbits of
SRAM for audio delay that is suitable for simulated surround functions and speaker compensation. The programmable
DSP allows up to 4608 execution lines per audio sample cycle at 8kHz, 768 lines at 48kHz, or 384 lines at 96kHz with
multiple functions per line. The AK7746 can be used to implement complete sound field control, such as echo, 3D,
parametric equalization, etc. It is packaged in a 64-lead LQFP.
1. General Description
2. Features
DSP:
- Word length: 24-bit (Data RAM)
- Instruction cycle time: 27ns (768fs, fs=48kHz )
- Multiplier: 24 x 16 → 40-bit
- Divider: 24 / 24 → 16-bit or 24-bit
- ALU: 34-bit arithmetic operation (Overflow margin: 4bit)
- 24-bit arithmetic and logic operation
- Shift+Register: 1, 2, 3, 4, 6, 8 and 15 bits shifted left
1, 2, 3, 4, 8 and 15 bits shifted right
(Other numbers in parentheses are restricted.
Provided with indirect shift function)
- Program RAM: 768 x 32-bit
- Coefficient RAM: 1024 x 16-bit
- Data RAM: 256 x 24-bit
- Offset RAM: 48 x 13-bit
(6144 x 12-bit / 3072 x 24-bit / 4096 x 12-bit + 1024 x 24-bit )
- Internal Memory: 72kbit SRAM
- Sampling frequency: 8kHz to 96kHz
- Serial interface port for micro-controller
- Master clock: 768fs@48kHz ( generated by PLL from 256fs or 384fs )
- Master/Slave operation
- Serial signal input port ( 8(10) ch ):16/20/24-bit : Output port ( 8ch + 4ch ): 24-bit

ADC: 4 channels (2 channels 2 sets )
- 24-bit 64 x Over-sampling delta sigma
- Sampling frequency: 8kHz to 96kHz
- DR: 98dBA ( fs=48 kHz Full-differential Input )
- S/N : 98dBA ( fs=48 kHz Full-differential Input )
- S/(N+D) : 91dB ( fs= 48 kHz Full-differential Input )
- Digital HPF (fc = 1Hz)
- Single-ended or Full-differential Input
ADC: Monaural 1 channel
- 24-bit 64x Over-sampling delta sigma
- Sampling frequency: 8kHz to 96kHz
- DR: 97dBA ( fs=48 kHz )
- S/N : 97dBA ( fs=48 kHz )
- S/(N+D) : 91dB ( fs= 48 kHz )
Other
- External Jump pin: 3(maximum)
- CRC error check function
- LRCLK and BITCLK input and output for slave mode
- Power supply: +3.3V±0.3V
- Operating temperature range: -40°C~85°C
- Package: 64pin LQFP (0.5mm pitch)
Audio DSP with 5-channel 24-bit ADC and Input Mux
AK7746