Digital Audio Fundamentals 421
Figure 14.8 : In (a) two convertors are joined by a serial link. Although simple, this system
is defi cient because it has no means to prevent noise on the clock lines causing jitter at the
receiver. In (b) a phase-locked loop is incorporated, which fi lters jitter from the clock.
Clock
Clock
ADC Parallel Data DAC
to
serial
Noise
Serial
to
parallel
Noise on data
is rejected
Analog
out
Analog
in
Clock jitter
due to noise
isnot
rejected
(a)
Clock
ADC Parallel Data DAC
to
serial
Noise
Serial
to
parallel
Noise on data
is rejected
Analog
in
Analog
out
Jitter-free
clock
Phase-
locked
loop
(b)