uda1334bt NXP Semiconductors, uda1334bt Datasheet - Page 8

• Manufacturer Part Number: uda1334bt
• Description: Low Power Audio Dac
• Manufacturer: NXP Semiconductors

Philips Semiconductors
8.4
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. No post-filter is 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 scales proportionally
with the power supply voltage.
2002 May 22
handbook, halfpage
Low power audio DAC
Filter stream DAC
3.0 V
V ref(DAC)
Fig.3 Power-on reset circuit.
C1
10 F
V DDA
13
12
50 k
50 k
UDA1334BT
CIRCUIT
RESET
MGU678
8
8.5
The UDA1334BT has an internal Power-on reset circuit
(see Fig.3) which resets the test control block.
The reset time (see Fig.4) is determined by an external
capacitor which is connected between pin V
ground. The reset time should be at least 1 s for
V
will be reset again for V
During the reset time the system clock should be running.
handbook, halfpage
ref(DAC)
V ref(DAC)
V DDD
V DDA
(V)
(V)
(V)
1.25
0.75
1.5
1.5
1.5
Power-on reset
3.0
3.0
3.0
0
0
0
< 1.25 V. When V
Fig.4 Power-on reset timing.
1 s
ref(DAC)
DDA
is switched off, the device
< 0.75 V.
UDA1334BT
Product specification
ref(DAC)
MGL984
and
t
t
t