UDA1342 PHILIPS [NXP Semiconductors], UDA1342 Datasheet - Page 10

• Manufacturer Part Number: UDA1342
• Description: Audio CODEC
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
8.8
The 5th-order noise shaper operates at 64f
in-band quantization noise to frequencies well above the
audio band. This noise shaping technique enables high
signal-to-noise ratios to be achieved. The noise shaper
output is converted into an analog signal using a Filter
Stream Digital-to-Analog Converter (FSDAC).
8.9
The FSDAC is a semi-digital reconstruction filter that
converts the 1-bit data stream of the noise shaper to an
analog output voltage. The filter coefficients are
implemented as current sources and are summed at
virtual ground of the output operational amplifier. In this
way very high signal-to-noise performance and low clock
jitter sensitivity is achieved. A post-filter is not needed due
to the inherent filter function of the DAC. On-board
amplifiers convert the FSDAC output current to an output
voltage signal capable of driving a line output.
The output voltage of the FSDAC is proportionally to the
power supply voltage.
2000 Mar 29
handbook, full pagewidth
Audio CODEC
Noise shaper
Filter stream DAC
decimation
interface
from
filter
digital
input
from
DE-EMPHASIS
VOLUME
VOLUME
MUTE
MUTE
AND
AND
s
. It shifts
Fig.5 Digital mixer (DAC).
10
8.10
The UDA1342TS supports the following data input/output
formats for the various modes (see Fig.6).
L3-bus and I
Static pin mode:
BASS BOOST
I
MSB-justified serial format with data word length of up to
24 bits
LSB-justified serial format with data word lengths of
16, 20 or 24 bits
MSB-justified data output and
LSB-justified 16, 20 and 24 bits data input.
I
MSB-justified data output and
LSB-justified 16, 20 and 24 bits data input.
TREBLE
2
2
AND
S-bus format with data word length of up to 24 bits
S-bus format with data word length of up to 24 bits
Digital interface
2
C-bus mode:
VOLUME
master
MUTE
AND
MGT019
Preliminary specification
UDA1342TS
interface
interpolation
output
digital
to
filter
to