AK4359_06 Datasheet, PDF (12/33 Pages) Asahi Kasei Microsystems – 106dB 192kHz 24-Bit 8ch DAC

ASAHI KASEI
[AK4359]
OPERATION OVERVIEW
„ System Clock
The external clocks, which are required to operate the AK4359, are MCLK, LRCK and BICK. The master clock (MCLK)
should be synchronized with LRCK but the phase is not critical. The MCLK is used to operate the digital interpolation
filter and the delta-sigma modulator. There are two methods to set MCLK frequency. In Manual Setting Mode (ACKS bit
= “0”: Register 00H), the sampling speed is set by DFS0-1 bits (Table 1). The frequency of MCLK at each sampling speed
is set automatically. (Table 2~Table 4) In Auto Setting Mode (ACKS bit = “1”: Default), as MCLK frequency is detected
automatically (Table 5), and the internal master clock becomes the appropriate frequency (Table 6), it is not necessary to
set DFS0-1.
In parallel control mode, the sampling speed can be set by only ACKS pin. When ACKS pin = “L”, the AK4359 operates
by Normal Speed Mode. When ACKS pin = “H”, Auto setting mode is enabled. The parallel control mode does not
support 128fs and 192fs of Double Speed Mode.
All external clocks (MCLK, BICK and LRCK) should always be present whenever the AK4359 is in the normal operation
mode (RSTB pin = ”H”). If these clocks are not provided, the AK4359 may draw excess current and may fall into
unpredictable operation. This is because the device utilizes dynamic refreshed logic internally. The AK4359 should be
reset by RSTB pin = “L” after threse clocks are provided. If the external clocks are not present, the AK4359 should be in
the power-down mode (RSTB pin = ”L”). After exiting reset(RSTB = “↑”) at power-up etc., the AK4359 is in the
power-down mode until MCLK is input.
DFS1
0
0
1
DFS0
0
1
0
Sampling Rate (fs)
Normal Speed Mode
8kHz~48kHz
Double Speed Mode
60kHz~96kHz
Quad Speed Mode
120kHz~192kHz
Table 1. Sampling Speed (Manual Setting Mode)
Default
LRCK
fs
32.0kHz
44.1kHz
48.0kHz
256fs
8.1920MHz
11.2896MHz
12.2880MHz
384fs
12.2880MHz
16.9344MHz
18.4320MHz
MCLK
512fs
16.3840MHz
22.5792MHz
24.5760MHz
768fs
24.5760MHz
33.8688MHz
36.8640MHz
1152fs
36.8640MHz
N/A
N/A
BICK
64fs
2.0480MHz
2.8224MHz
3.0720MHz
Table 2. System Clock Example (Normal Speed Mode @Manual Setting Mode)
MS0289-E-02
- 12 -
2006/03