
2–4
Table 2–2. Mute Description
MUTE
PWM_P
PWM_M
DESCRIPTION
0
50% Duty cycle
Mute
1
DATA
Normal operation
2.7.5
Double Speed
Double-speed mode is used to support sampling rates of 88.2 kHz and 96 kHz. In order to put the TAS5000 in
double-speed mode with the device in normal operating conditions, the RESET pin must be held low while switching
the DBSPD pin high. After RESET pin is brought high again, a reset sequence takes place (see paragraph 2.7.2).
If the change is at power up, a power up sequence is originated (see paragraph 2.7.1).
2.7.6
De-Emphasis Filter
For audio sources that have been pre-emphasized, a precision 50
s/15 s de-emphasis filter is provided to support
the sampling rates of 44.1 kHz and 48 kHz. Pins DEM_SEL and DEM_EN select the de-emphasis functions. See
Figure 2–5 for a graph showing the de-emphasis filtering characteristics. See Table 2–3 for de-emphasis selection.
When the DEM_EN pin or the DEM_SEL pin change state, the PWM outputs go into the quiet mute state. After 128
LRCLK periods for initialization, the PWM outputs are driven to the normal (unmuted) mode.
0
–10
Response
–
dB
3.18 (50
s)
10.6 (15
s)
f – Frequency – kHz
De–emphasis
Figure 2–5. De-Emphasis Filter Characteristics
2.7.6.1 De-Emphasis Selection
De-emphasis selection is accomplished by using the DEM_SEL and DEM_EN pins. See Table 2–3 for de-emphasis
selection description.
Table 2–3. De-Emphasis Selection
DEM_SEL
DEM_EN
DESCRIPTION
X
0
De-emphasis disabled
0
1
De-emphasis enabled for Fs = 44.1 kHz
1
De-emphasis enabled for Fs = 48 kHz
2.7.7
Error Status Reporting (ERR pin)
The following is a list of the error conditions that will cause the ERR status pin to be asserted low:
No clocks
Clock phase errors
When any of the above conditions is met, the ERR will go low and the PWM outputs will go to the hard mute state.
If the error condition is removed, the TAS5000 is reinitialized and the ERR pin will be asserted high.
2.8
Serial Interface Formats
The TAS5000 is compatible with eight different serial interfaces. Available interface options are IIS, right justified, left
justified, and DSP Frame. Table 2–4 indicates how these options are selected using the MOD0, MOD1, and MOD2
pins.