© 2006 - 2008 TOSHIBA TEC CORPORATION All rights reserved
GD-1220/1221
ELECTRICAL CIRCUITS
4 - 11
4
EU/AU/AS/C models
Fig. 4-11
The CI detection circuit consists of the photocoupler (PC1), ASIC (IC23) on the MAIN board and other
peripheral devices to detect a ring signal input from the telephone line.
The ASIC makes the CML1 signal become LOW to connect the CI detection circuit to the line. When a
ring signal is input from the telephone line, the photocoupler is repeatedly turned ON/OFF. This allows
Q5 to be turned ON/OFF and the CI1 signal to become a pulse signal and input to the ASIC on the
MAIN board, thereby detecting the ring signal.
Signal Name
Type
Active
Description
Destination
CI1
I
-
Line 1 CI Detection Signal
IC23
CN3
Lb
La
Line
0
1
0
10
3
12
1
4
9
1
+12V
RLY3
CML relay
CML1
Q4
3
4
3
3
27
65
17
NCU board
FAX board
IC23
ASIC
CI1
17
1
2
4
3
AG
Q5
SG
5VPS
R34
R35
CN
4
CN
262
PC1
ZD3
ZD2
C8
R4
D2
CN
5
CN
5
27
65
144
162
MAIN board
Содержание GD-1221
Страница 1: ...SERVICE MANUAL FACSIMILE GD 1220 1221 File No SME060017B0 R060121B2200 TTEC Ver02_2008 08 ...
Страница 6: ...GD 1220 1221 2006 2008 TOSHIBA TEC CORPORATION All rights reserved CONTENTS 2 ...
Страница 34: ...GD 1220 1221 2006 2008 TOSHIBA TEC CORPORATION All rights reserved LSU RELATED FUNCTIONS 2 16 ...
Страница 60: ...GD 1220 1221 2006 2008 TOSHIBA TEC CORPORATION All rights reserved DIALING COMMUNICATION CONTROL 3 26 ...
Страница 78: ...GD 1220 1221 2006 2008 TOSHIBA TEC CORPORATION All rights reserved ELECTRICAL CIRCUITS 4 18 ...
Страница 80: ...GD 1220 1221 2006 2008 TOSHIBA TEC CORPORATION All rights reserved INSTALLATION 5 2 ...
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