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14
KX-HT82480/82470/82460 Series
4.2.1.7.
Polarity Reversal Detection
Configured by the photo couplers (PC900/901) that enable to detect each current in Tip
Ring, Ring Tip direction.
PC901 is used in common as the bell detection photo coupler. Using software, it stores the current direction (the detected photo
coupler) at acquiring line and recognizes the action by changing of the current direction (the detected photo coupler changes).
coupler) at acquiring line and recognizes the action by changing of the current direction (the detected photo coupler changes).
When the current flows in the direction of Ring to Tip, PC900 4-pin (BELLDET) is Low and PC901 4-pin (REVDET) is High.
1. Ring
R902 PC900 D908 Q900(C-E) Q904(C-E) R920 D904 Tip
When the current direction (polarity) is reversed from Tip to Ring, PC900 4-pin (BELLDET) is High and PC901 4-pin (REVDET)
turns to Low level. It recognizes the action by changing of the current direction (the detected photo cpupler changes).
turns to Low level. It recognizes the action by changing of the current direction (the detected photo cpupler changes).
2. Tip
D904 R920 Q904(C-E) Q900(C-E) D908 PC901 R901 Ring
4.2.1.8.
2W-4W Conversion
This circuit converts 4W-voice signal inside PBX and 2W-voice signal on SLT line side. It is configured by Op-Amp in HIC and BN
(Balance Network) in CODEC. It determines the return loss of voice and the frequency characteristic, and it can match with sorts of
impedance by changing the programs of CODEC.
(Balance Network) in CODEC. It determines the return loss of voice and the frequency characteristic, and it can match with sorts of
impedance by changing the programs of CODEC.
BELL DET
REV DET
+
-
+
-
+
-
REVDET[0]
DP[0]
*RL900A
NC
1
2
3
4
*D904A
NC
2
1
R930A
C926A
IC909A
3
2
1
R944A
D910A
+3.3V_DE56_2
C930A
C935A
C901A
+3.3V_DE56_2
VH1
DG
+3.3V_DE56_2
+3.3V_DE56_2
IC909A
5
6
7
R943A
PC900A
1
23
4
VH1
C904A
C924A
DG
R936A
C921A
C933A
DG
PC903A
1
2
3
4
R920A
C908A
+3.3V_DE56_2
*R901A
+3.3V_DE56_2
R946A
Q900A
C906A
*C905A
*C907A
D908A
3
1
2
4
DG
PC902A
1
3
4
6
*C912A
T900A
3
1
6
4
5
*D902A
*D906A
R981A
VH1
R980A
DG
C960A
*ZNR900A
*C937A
*R908A
*R932A
*C916A
*R938A
*C918A
*R954A
*C928A
*R906A
*R904A
*R948A
*R922A
*R916A
*R934A
*R940A
PC901A
1
2
3
4
*C910A
*Q904A
*R900A
R902A
22
R914A
R918A
R924A
R926A
R928A
680
R950A
R956A
REVDET
BELLDET
Pattern 1
BELL DET
REVDET
Pattern 2
OFF HOOK
REVERSE
OFF HOOK
REVERSE
+
-
+
-
SIGN6843
C926A
IC909A
3
2
1
R944A
C930A
C935A
VH1
DG
IC909A
5
6
7
R943A
VH1
C924A
IC909A
4
VEE
8
VCC
R936A
C921A
C933A
+15V
R946A
*C912A
T900A
3
1
6
4
5
R981A
VH1
R980A
DG
C960A
*C937A
*R932A
*C916A
*R938A
*C918A
*R954A
*C928A
*R948A
*R934A
*R940A
R950A
R956A
From DSP
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