uda1340 NXP Semiconductors, uda1340 Datasheet - Page 7

• Manufacturer Part Number: uda1340
• Description: Low-voltage Low-power Stereo Audio Codec With Dsp Features
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Interpolation filter (DAC)
The digital filter interpolates from 1f
a cascade of a recursive filter and an FIR filter.
Table 3 Interpolation filter characteristics
Noise shaper (DAC)
The 3rd-order noise shaper operates at 128f
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.
1997 Jul 09
Passband ripple
Stop band
Dynamic range
Gain
Low-voltage low-power stereo audio
CODEC with DSP features
ITEM
CONDITION
0
0
>0.55f
DC
0.45f
0.45f
s
s
s
s
to 128f
VALUE (dB)
s
s
by means of
. It shifts
108
0.03
3.5
50
7
The Filter Stream DAC (FSDAC)
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.
Preliminary specification
UDA1340