2–4

Table 2–2. Mute Description

MUTE

PWM_P

PWM_M

DESCRIPTION

0

50% Duty cycle

50% Duty cycle

Mute

1

DATA

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

µs/15 µs 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

3.18 (50

µs)

10.6 (15

µs)

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

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.