[AK7742]
AK7742
24bit 2ch ADC + 24bit 4ch DAC with Audio DSP
GENERAL DESCRIPTION
The AK7742 is a highly integrated audio digital processor, including two stereo 24bit DAC’s and one
stereo ADC with input selector. The stereo DAC and ADC feature high performance, archiving 106dB and
96dB dynamic range respectively, 8kHz to 96kHz sampling rate are supported. The audio DSP has
1536step/fs parallel processing power, and 74k-bit delay memory allows surround processing, acoustic
effect and parametric equalizers. As the AK7742 is a RAM based DSP, it is programmable for user
requirements. The AK7742 is available in a space saving small 48pin LQFP package.
FEATURES
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DSP:
- Word length: 24bit (Data RAM 24bit floating point)
- Instruction cycle: 13.6 ns (1536step/fs fs=48kHz; 9216step/fs fs=8kHz)
- Multiplier 20 x 16
→
36bit (double precision available)
- Divider 20 / 20
→
20bit
- ALU: 40bit arithmetic operation (overflow margin 4bit) 24bit floating point arithmetic and
logic operation
- Program RAM: 1536 x 36bit
- Coefficient RAM: 1536 x 16bit
- Data RAM: 1536 x 24-bit (24bit floating point)
- Delay RAM: 74kbit (3072 x 24bit)
- Sampling frequency: 8kHz
~
96kHz
- Master / Slave operation
- Serial signal input port (4ch) MSB justified 24bit / LSB justified 24 / 20 / 16bit and I
2
S
- Serial signal output port (6ch) MSB justified 24bit / LSB justified 24 / 16bit and I
2
S
ADC: 2ch (stereo)
- 24bit 64 x Over-sampling delta sigma (fs=8kHz~48kHz)
- DR, S/N: 96dB (fs=48kHz, fully differential input)
- S/(N+D): 84dB (fs=48kHz)
- Differential, Single-end Inputs
- Digital HPF (fc=1Hz)
- 3:1 Analog input selector
- Digital Volume (24dB~-103dB, 0.5dB Step, Mute)
DAC: 4ch (two stereo pairs)
- 24bit 128 x Over-sampling advanced multi-bit (fs=8kHz~96kHz)
- DR, S/N: 106dB
- S/(N+D): 92dB
- Differential output
- Digital Volume (12dB~-115dB, 0.5dB Step, Mute)
DSP Through Mode
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I
2
C BUS interface for micro-controller
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Power supply: +3.3V
±0.3V,
internal regulator for 1.8V
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Operating temperature range: -20°C~70°C (AK7742EQ), -20°C~85°C (AK7742EN)
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Package: 48pin LQFP, 0.5mm pitch (AK7742EQ)
48pin QFN, 0.4mm pitch (AK7742EN)
MS1024-E-00
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1
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2008/11