msm7617 Oki Semiconductor, msm7617 Datasheet - Page 9

• Manufacturer Part Number: msm7617
• Description: 2-channel Echo Canceler
• Manufacturer: Oki Semiconductor

¡ Semiconductor
PIN DESCRIPTIONS (Continued)
Pin
24
25
26
27
29
30
Symbol
RGC11
RGC10
SG11
SG10
SA11
SA10
Type
I
I
I
RGC11
S output gain control pins for channel 1 (refer to the block diagram).
These pins amplify the output level of SOUT. The gain level can be set even
during the echo canceler disable mode.
S input attenuator control pins for channel 1 (refer to the block diagram).
These pins attenuate the input level of SIN. Use them if ERL is large.
The attenuation level can be set even during the echo canceler disable mode.
R input level control pins for channel 1 (refer to the block diagram).
Excessive input (PCM level is at maximum value) causes a malfanction.
Use these pins when there is a possibility of excessive input.
SG11
SA11
0
0
1
1
0
0
1
1
0
0
1
1
RGC10
SG10
SA10
0
1
0
1
0
0
0
1
1
1
0
1
Gain Level
0 dB
+6 dB
+12 dB
Not used
Attenuation Level
0 dB
–6 dB
–12 dB
Not used
Level Control Mode
Off
GC: On (control level = –20 dBm0)
By the R gain controller, levels from –20 to –11.5 dBm0 will
be suppressed to –20 dBm0 and those above –11.5 dBm0 will
always be attenuated by 8.5 dB. This is effective to prevent
excessive input and howling for hands-free applications.
Inhibited
±6LR: On
Applies –6 dB to excessive inputs using the level adjuster
provided on R and S I/O. Since +6 dB also is applied at the
output, the total level will not change, making this effective
against line echo.
Description
MSM7617
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