PAI
PAO+
PAO-
R4 1K
C8
330 pF
LS1
32 Ohm SPEAKER
R6 91K
R5 91K
R7 20K
VDD
+
-
VAG
R2
1.5K
C7 330 pF
R1
1.5K
RO-
R9
SELECT
M1
C4 4.7uF
SIDETONE LEVEL CONTROL
C3 0.1uF
AO
R10
1K
AI+
R8 3K
AI-
TO FILTERS AND ENCODER
R3 1K
FROM FILTER AND DECODER
C2 0.1uF
Figure 2: VoIP Phone Set Diagram
C3 0.1uF
to 600 Ohm Line/Load
R14
300 OHM
Note: R13 and R14
are not on board
R6 10K
R8 27K
R13
300 OHM
AI-
VAG
R7 27K
RO-
C2 0.1uF
TO FILTERS AND ENCODER
LINE IN
R3 10K
R5 10K
FROM FILTER AND DECODER
+
-
AI+
LINE OUT
R4 10K
PAI
PAO+
PAO-
AO
Figure 3: 600 Ohm Line IN/OUT Diagram
5
