AK7744VT Datasheet, PDF (20/50 Pages) Asahi Kasei Microsystems – 24bit 3ch ADC + 24bit 4ch DAC with Audio DSP

[ASAHI KASEI]
[AK7744]
8. Function Description
(1) Various setting
1-1) SMODE : slave and master mode selector pin
Sets LRCLK and BITCLK to either inputs or outputs.
a) Slave mode :SMODE="L"
LRCLK(1fs) and BITCLK (64fs or 48fs ) become inputs.
b) Master mode: SMODE="H"
LRCLK (1fs) and BITCLK (64fs) become outputs.
Note) SMODE pin is to be fixed “L” or “H”. Therefore, after release an initial reset ( INIT_RESET =”L”→”H”)
SMODE must change during the system reset state ( S_RESET ="L") . This is especiallty critical in slave mode, as
phase matching between internal and external clocks begins when a system reset occurs (See (8.(4)) Resetting). DO
NOT CHANGE SMODE during runtime, as this will cause an error.
(2) Control registers
The control registers can be set via the microcomputer interface or the control pins. These registers consist of 4
addresses and each register is 8-bits. For the value to be written in the control registers see the microcomputer
interface description. The following describes the control register map.
0).
Command Code
Write Read
60h
70h
64h
74h
68h
78h
6Ch 7Ch
Name
CONT0
CONT1
CONT2
CONT3
TEST: for TEST (input 0,X: it ignore input data, but should input
D7
D6
D5
D3
D4
D2
D1
D0 Default
CFS1
CFS0
DIF
DIF1
DIF0
DISCK SELCKO X
00h
DATARAM
RM
BANK CMP_N
SS[1]
SS[0]
TEST
X
00h
SWA2
SWA1
SWD2
SWD1 PSDA2 OUTE
TEST
X
00h
ISEL2
ISEL1[2] ISEL1[1] ISEL1[0] PSAD2 PSAD1
TEST
X
00h
1. CONT0 can be set only at system reset ( S_RESET ="L").
2. CONT1~2 should be set at system reset ( S_RESET ="L" ), otherwise some noise can come out.
3. The input selector (CONT3) can be changed “on the fly”. However it must change synchronously with the
initialization of the ADC’s digital interface. For example: ADC1, the input selector (CONT3: ISEL1[2:0]) and
CONT3:PSAD1=1 should change at the same time. After CONT3:PSAD1=0, then the ADC1 digital interface
can be initialized. When changing CONT3 on the fly, some noise will occur, so an external mute circuit after the
DAC output should be used. ADC2 can also cause some noise.
4. Default setting is the same value as an initial reset ( INIT_RESET =”L” ).
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2002/10