¡ Semiconductor
MSM7620
HOW TO USE THE MSM7620
The MSM7620 cancels the echo which returns to SIN using the RIN signal.
Connect the base signal to the R-side and the echo generated signal to the S-side.
Connection Methods According to Echos
Example 1:
Canceling acoustic echo (to handle acoustic echo from line input)
CODEC
MSM7620
CODEC
ROUT
RIN
Acoustic echo
m-law
AFF
SIN +
–
m-law
SOUT
+
Line input
H
Example 2: Canceling line echo (to handle line echo from microphone input)
Microphone Input
CODEC
MSM7620
CODEC
RIN
ROUT
m-law
SOUT
AFF
– + SIN
+
m-law
H
Line echo
Example 3:
Canceling line echo in a cascade connection
(to handle line echo from microphone input)
Microphone input
CODEC
MSM7620
CODEC
RIN Master ROUT
AFF
m-law
SOUT
–
+ SIN
m-law
H
H
+
PD0 - 15
Slave
AFF
Line echo
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