Architecture Overview
11
SLES089—January 2004
TAS5066
2.1.6 DCLK
DCLK is the internal high frequency clock that is produced by the PLL circuitry from MCLK. The TAS5066 uses
the DCLK to control all internal operations. DCLK is 8 times the speed of MCLK in normal speed mode, 4 times
MCLK in double speed, and 2 times MCLK in quad speed. With respect to the I2C addressable registers, DCLK
clock cycles are used to specify interchannel delay and to detect when the MCLK frequency is drifting.
Table 24, DCLK, shows the relationship between sample rate, MCLK, and DCLK.
Table 24. DCLK
Fs
(kHz)
MCLK
(MHz)
DCLK
(MHz)
DCLK Period
(ns)
32
8.1920
65.5360
15.3
44.1
11.2896
90.3168
11.1
48
12.2880
98.3040
10.2
88
22.5280
90.1120
11.1
96
24.5760
98.3040
10.2
192
49.1520
98.3040
10.2
2.1.7 Serial Data Interface
The TAS5066 operates as a slave only/receive only serial data interface in all modes. The TAS5066 has three
PCM serial data interfaces to accept six channels of digital data though the SDIN1, SDIN2, SDIN3 inputs. The
serial audio data is in MSB first; 2s complement format.
The serial data interfaces of the TAS5066 can be configured in right justified, I2S, left-justified, or DSP modes.
This interface supports 32-kHz, 44.1-kHz, 48-kHz, 88-kHz, 96-kHz, 176.4-kHz, and 192-kHz data sample
rates. The serial data interface format is specified using the data interface control register. The supported word
lengths are shown in Table 25.
During normal operating conditions if the serial data interface settings change state, an error recovery
sequence is initiated.
Table 25. Supported Word Lengths
DATA MODES
WORD
LENGTHS
MOD2
MOD1
MOD0
Right justified, MSB first
16
0
Right justified, MSB first
20
0
1
Right justified, MSB first
24
0
1
0
I2S
16
0
1
I2S
20
1
0
I2S
24
1
0
1
Left justified, MSB first
24
1
0
DSP frame
16
1
2.1.7.1
I2S Timing
I2S timing uses an LRCLK to define when the data being transmitted is for the left channel and when it is for
the right channel. The LRCLK is low for the left channel and high for the right channel. A bit clock running at
48 or 64 times Fs is used to clock in the data. There is a delay of one bit clock from the time the LRCLK signal
changes state to the first bit of data on the data lines. The data is written MSB first and is valid on the rising
edge of the bit clock. The TAS5066 masks unused trailing data bit positions. Master mode only supports a 64
times Fs bit clock.