uda1334ats NXP Semiconductors, uda1334ats Datasheet - Page 7

• Manufacturer Part Number: uda1334ats
• Description: Low Power Audio Dac With Pll
• Manufacturer: NXP Semiconductors

Philips Semiconductors
8
8.1
The UDA1334ATS incorporates a PLL capable of
generating the system clock. The UDA1334ATS can
operate in 2 modes:
In video mode, the digital audio input is slave, which
means that the system must generate the BCK and
WS signals from the output clock available at pin CLKOUT
of the UDA1334ATS. The digital audio signals should be
frequency locked to the CLKOUT signal.
Remarks:
1. The WS edge MUST fall on the negative edge of the
2. For LSB-justified formats it is important to have a WS
8.1.1
Audio mode is enabled by setting pin PLL0 to LOW.
De-emphasis can be activated via pin DEEM/CLKOUT
according to Table 5.
In audio mode, pin SYSCLK/PLL1 is used to set the
sampling frequency range as given in Table 1.
Table 1 Sampling frequency range in audio mode
8.1.2
In video mode, the master clock is a 27 MHz external clock
(as is available in video environment). A clock-out signal is
generated at pin DEEM/CLKOUT. The output frequency
can be selected using pin PLL0. The output frequency is
either 12.228 MHz (256
MID level or 18.432 MHz (384
being HIGH, as given in Table 2.
2000 Jul 31
SYSCLK/PLL1
It operates as an asynchronous DAC, which means the
device regenerates the internal clocks using a PLL from
the incoming WS signal. This mode is called audio
mode.
It generates the internal clocks from a 27 MHz clock
input, based on 32, 48 and 96 kHz sampling
frequencies. This mode is called video mode.
Low power audio DAC with PLL
BCK at all times for proper operation of the digital I/O
data interface
signal with a duty factor of 50%.
FUNCTIONAL DESCRIPTION
HIGH
System clock
LOW
A
V
UDIO MODE
IDEO MODE
f
f
s
s
= 16 to 50 kHz
= 50 to 100 kHz
48 kHz) with pin PLL0 being at
SELECTION
48 kHz) with pin PLL0
7
Table 2 Clock output selection in video mode
Notes
1. The supported sampling frequencies are:
2. The supported sampling frequencies are:
8.2
The interpolation digital filter interpolates from 1f
by cascading FIR filters (see Table 3).
Table 3 Interpolation filter characteristics
8.3
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 DAC (FSDAC).
Pass-band ripple
Stop band
Dynamic range
96, 48 and 24 kHz or 64, 32 and 16 kHz.
96, 48 and 24 kHz; 72 and 36 kHz or 32 kHz.
PLL0
HIGH
ITEM
LOW
Interpolation filter
Noise shaper
MID
12.228 MHz clock; note 1
18.432 MHz clock; note 2
audio mode
CONDITION
0f
0f
s
s
>0.55f
to 0.45f
to 0.45f
s
SELECTION
s
s
UDA1334ATS
Product specification
VALUE (dB)
s
. It shifts
>114
0.02
50
s
to 64f
s