[AK7780]
AK7780
24bit 5ch ADC & SRC + Audio DSP
GENERAL DESCRIPTION
The AK7780 is a highly integrated audio processor, including a 28-bit floating point DSP, two 24-bit stereo
ADC’s and one mono ADC. The stereo ADC’s feature high performance, achieving 96dB dynamic range,
they include 8:1 input selectors. The ADC supports sampling frequencies from 7.35 kHz to 96 kHz. The
AK7780 also includes a stereo sample rate converter (SRC), so it can be used as a master device when
it receives digital audio inputs. The DSP includes 168kbits of SRAM for audio delay data that is suitable
for creating simulated surround fields. The programmable DSP block is realized with 2560step/fs DSP. It
supports sampling frequencies from 7.35kHz to 96 kHz. The AK7780 is used to implement complete
sound field control, such as echo, 3D, parametric equalization, and other sound enhancements. It is
packaged in a 100-lead LQFP package.
FEATURES
[DSP]
Main
Word length: 28-bit (Data RAM F24.4 limited range floating point)
Instruction cycle time: 8.1 ns (2560step/fs fs=48kHz; 1280step/fs fs=96kHz)
Multiplier: 24 x 16
→
40-bit (Double precision available)
Divider: 24 / 24
→
24-bit
ALU: 44-bit arithmetic operation (overflow margin: 4-bits)
F24.4 arithmetic and logic operation
Shift+Register: Flexible setting
Program RAM: 2048 x 36-bit
Coefficient RAM: 2048 x 16-bit
Data RAM: 2048 x 28-bit (F24.4[sign bit + 23-bit mantissa + 4-bit exponent])
Offset RAM: 64 x 13-bit
Internal Delay RAM: 168kbits
( 6144 x 28 bit / 2048 x 28 bit + 8192 x 14 bit / 3072 x 28 bit + 6144 x 14 bit
/ 4096 x 28 bit + 4096 x 14 bit) 4 pattern setting
28bit = F24.4 [24 bit sign & mantissa: 4 bit exponent]
14bit = F10.4 [10 bit sign & mantissa: 4 bit exponent]
Sampling frequency: 7.35kHz ~ 96kHz
Serial interface port for microcontroller or I
2
C BUS control
Master Clock: 2560fs (generated by PLL from 32fs ,64fs, 256fs and 384fs)
Master/Slave operation
Serial signal input port (10ch): MSB justified 24-bit / LSB justified 16/20/24-bit and I
2
S
Serial signal output port(12ch): MSB justified 24-bit / LSB justified 24,16-bit and I
2
S
(SDOUT1,SDOUT2 and SDOUT3)
[ADC]
4 channels (2 stereo pairs)
24-bit 64X over-sampling delta-sigma (fs = 7.35kHz ~ 96kHz)
DR, S/N: 96dBA (fs = 48kHz, fully-differential input)
S/(N+D): 92dB (fs = 48kHz)
Digital HPF (fc = 1Hz)
MS0581-E-00-PB
-1-
2007/09
AKM [ ASAHI KASEI MICROSYSTEMS ]
