AK4458 Datasheet, PDF (64/84 Pages) Asahi Kasei Microsystems – 115dB 768kHz 32-bit 8ch Premium DAC

[AK4458]
(1) 3-wire Serial Control Mode (I2C pin = “L”)
The internal registers may be written through the 3-wire µP interface pins (CSN, CCLK and CDTI). The
data on this interface consists of a 2-bit Chip address, Read/Write (1bit, Fixed to “1”, Write only),
Register address (MSB first, 5bits) and Control data (MSB first, 8bits). Address and data are clocked in
on the rising edge of CCLK and data is clocked out on the falling edge. For write operations, data is
latched after a low-to-high transition of CSN. The clock speed of CCLK is 5MHz (max).
The internal registers are initialized by setting the PDN pin = “L”. In serial mode, an internal timing
circuit is reset by setting RSTN bit = “0” but register values are not initialized.
CSN
CCLK
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
CDTI
C1 C0 R/W A4 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0
C1-C0: Chip Address (C1= CAD1 pin, C0= CAD0 pin)
R/W: Read/Write (Fixed to “1”, Write only)
A4-A0:Register Address
D7-D0:Control Data
Figure 63. 3-wire Serial Control I/F Timing
* The AK4458 does not support read commands in 3wire serial control mode.
* When the AK4458 is in power down mode (PDN pin = “L”), writing into the control registers is
prohibited.
* The control data cannot be written when the CCLK rising edge is 15 times or less or 17 times or more
during CSN is “L”.
014011794-E-01
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2015/08