O
V E R V I E W
D K - A
U D I O
MSD100 U
SER
’
S
M
A N U A L
2 -5
2 . 6 C
O D E C
C
I R C U I T
The Codec circuit, included only on models MSD100,
MSD100T, MSD100T-SA, and MSD150C, integrates key
audio data conversion and control into a single IC. The
Codec circuits include the following features:
Anti-alias filter
Low-pass filter used at the input of the ADC
for determining the upper cut-off frequency
(f
max
) of the analog signal before conversion
to digital.
Anti-imaging
filter
Steep low-pass filter used after the DAC to
reduce the stair-step waveform (w/ high
frequency artifacts or images) and
reconstruct a smooth replica of the original
signal.
ADC
Analogue-to-digital converter. Circuit that
converts an analogue signal to a digital
signal.
DAC
Digital-to-analogue converter. Circuit that
converts a digital signal to an analogue
signal.
Gain control
Independent for each channel
Digital
attenuator
Attenuates signals before the DAC input
Digital
interpolation
filter
Provides oversampling and stereo
separation before the DAC input
Switched
capacitor and
continuous-
time filters
On-chip circuit for removing Nyquist images
from the DAC’s analogue stereo pairs
