Architecture Overview
18
SLES068A—February 2003—Revised January 2004
TAS5026A
This register indicates an error condition by a high for the following conditions:
FS ERROR
A control terminal change has occurred (M_S, DBLSPD)
LRCLK error
MCLK_IN count error
DCLK phase error with respect to MCLK_IN
MCLK_IN phase error with respect to DCLK
PWM timing error
If all bits of the register are low, no errors have occurred and no control terminals changed.
There is no one-to-one correspondence of clock error indication to a system error condition. A particular
system error can be indicated by one or more error indications in this register. The system error conditions
and the reported errors are as follows:
There is no correct number of MCLKs per LRCLK:
FS error has occurred
LRCLK error
MCLK_IN count error
LRCLK is absent:
LRCLK error
MCLK is the wrong frequency, changing frequency, or absent:
DCLK phase error with respect to MCLK
MCLK phase error with respect to DCLK
PWM timing error
SCLK is the wrong frequency or absent:
SCLK error
2.3
Signal Processing
This section contains the signal processing functions that are contained in the TAS5026A. The signal
processing is performed using a high-speed 24-bit signal processing architecture. The TAS5026A performs
the following signal processing features:
Individual channel soft volume with a range of 24 dB to 114 dB plus mute
Soft mute
Automute
50-
s/15-s de-emphasis filter supported in the sampling rates 32 kHz, 44.1 kHz, and 48 kHz
2.3.1 Volume Control
The gain of each output can be adjusted by a soft digital volume control for each channel. Volume adjustments
are performed using a soft gain update s-curve, which is approximated using a second order filter fit. The curve
fit is performed over a transition interval between 41 ms and 65 ms.
The volume of each channel can be adjusted from mute to 114 dB to 24 dB in 0.5 dB steps. Because of the
numerical representation that is used to control the volume, at very low volume levels the step size increases
for gains that are less than 96 dB. The default volume setting following power up or reset is 0 dB for all
channels. The step size adjustment is linear down to approximately 90 dB, see see Figure 210.