AK4103A_09 Datasheet, PDF (20/27 Pages) Asahi Kasei Microsystems – 192kHz 24-Bit DIT

[AK4103A]
■ Serial Control Interface
In asynchronous mode, four of the dual function pins become CSN, CCLK, CDTI and CDTO, a 4 wire microprocessor
interface. The internal 18 byte control register can then be read and written. The contents of the control register define,
in part, the mode of operation for the AK4103A. Figure 19 illustrates the serial data flow associated with SCI read and
write operations. C1-0 bits are the chip address. The AK4103A looks for C1-0 bits to be a “11” before responding to
the incoming data. R/W is the Read/ Write bit which is “0” for a read operation and “1” for a write operation. The
register address contained in A7-0 bits is decoded to select a particular byte of the control register. D7-0 bits on CDTI
pin is the control data coming from the microprocessor during a write operation. D7-0 bits on CDTO pin is the contents
of the addressed byte from the control register requested during a read operation. The address and data bits are framed
by CSN pin = “0”. During a write operation, each address and data bit is sampled on the rising edge of CCLK. During a
read operation, the address bits are sampled on the rising edge of CCLK while data on CDTO is output on the falling
edge of CCLK. CCLK has a maximum frequency of 5 MHz.
CSN
CCLK
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
CDTI
WRITE
CDTO
READ
CDTI
CDTO
C1 C0 * * * * * R/W A7 A6 A5 A4 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0
Hi-Z (with pull-down resistor)
“L”
C1 C0 * * * * * R/W A7 A6 A5 A4 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0
Hi-Z (with pull-down resistor)
Hi-Z
D7 D6 D5 D4 D3 D2 D1 D0
C1-C0: Chip Address (Fixed to “11”)
R/W: READ/WRITE (0:READ, 1:WRITE)
*: Don’t care
A7-A0: Register Address
D7-D0: Control Data
Figure 19. Control I/F Timing
AK4103A
CSN
CCLK
CDTI
CDTO
AK4103A
CSN
CCLK
CDTI
CDTO
μP
CSN1
CCLK
CDTI
CDTO
CSN2
Figure 20. Typical connection with μP
Note:External pull-up resistor should not be attached to CDTO pins
since CDTO pin is internally connected to the pull-down resistor.
MS0251-E-01
- 20 -
2009/01