Harman Kardon FL8400 - Page 19

FL8400
—_
4, 1-bit D/A Converter
Flg. 10 Shows the configuration of the SM5871.
Filter & Noise
Interface Atteruation Shaper
Fig. 10
The
sampling
frequency
of
the
input
data
is
expressed
in
fs,
so
the 3rd
order
noise
shaping
circuit
operates
at
32fs.
This
means
that
a
32-times
oversampling
filter
is vequired.
In
this
LSI,
oversampling
is
carried
out
the
multiple
stage.
Fig.
11
shows
the
configuration
of
filter,
attenuation,
and
noise
shaper.
+ input fs/16 BIT
Demphasis IIR Filter
{ fs/18BIT
Attenuator
¥
fs |
2X Interpolator 45th orders FIR
+ 2fs
2X interpolator 9th order FIR ] Bis
DF section
1 4ts
2X Interpolator 5th orders F2R
+ 8fs —
Sample holder
1 32%s >
3rd orders ZSNS ‘| £.A DAC section
{£DECO}
| 32fs
PWM module ]
¥
PWM output
Fig. 11
19