Panasonic KX-TDA6174XJ / KX-TDA6174X Service Manual ▷ View online
7.9. SURGE PROTECTION
ZNRs installed between T and R, and between T or R and FG protect from extraneous surge.
7.10. SELF-DIAGNOSIS
A self-diagnosis relay (RL201A) is installed in A port. In the normal operation mode, it breaks the self-diagnosis relay, and in the
self-diagnosis mode, it makes the self-diagnosis relay. In the self-diagnostic mode, A Tip-Ring is connected to the paired Tip-Ring
of the outside-line card via backboard, and self-diagnosis is feasible.The self-diagnosis of the outside-line card includes outside call
pick up, dial pulse transmission, DTMF transmission, BELL reception and CPC detection.
self-diagnosis mode, it makes the self-diagnosis relay. In the self-diagnostic mode, A Tip-Ring is connected to the paired Tip-Ring
of the outside-line card via backboard, and self-diagnosis is feasible.The self-diagnosis of the outside-line card includes outside call
pick up, dial pulse transmission, DTMF transmission, BELL reception and CPC detection.
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7.11. POWER FAILURE SWITCH FEATURE
4 out of 16 lines have switching relays (RL200A-D) installed in order to enable the outside call during a power failure. The line
connected to the outside call card will be directly connected to the CN201/202 located in forward part of the board via a 4-conductor
TEL cord. In the normal operation mode, it breaks the power failure switching relay, and during a power failure, it makes the power
failure switching relay to initiate Power failure direct connection mode.
connected to the outside call card will be directly connected to the CN201/202 located in forward part of the board via a 4-conductor
TEL cord. In the normal operation mode, it breaks the power failure switching relay, and during a power failure, it makes the power
failure switching relay to initiate Power failure direct connection mode.
7.12. BELL SIGNAL GENERATOR
Bell signal for ringing an SLT is generated by amplifying the 20 or 25Hz square wave provided from EMPR card to AC75Vrms
onboard. The SW power supply in the BELL circuit generates between +160V and -100V of voltage by switching the +40V from the
power source at 125KHz frequencies. The Bell signal picks up the square wave provided from EMPR via a photocoupler, and it is
transformed into SIN wave, then amplified to AC75Vrm bell signal by the amplitude between +160V and -100V of voltage (Mainly
+30Vdc) produced by SW power supply. When the Bell signal is not needed, bell signal voltage generating circuit can be turned
off by transmitting H signal from P21 port (BELL CNT) of ASIC to reduce the power consumption.
onboard. The SW power supply in the BELL circuit generates between +160V and -100V of voltage by switching the +40V from the
power source at 125KHz frequencies. The Bell signal picks up the square wave provided from EMPR via a photocoupler, and it is
transformed into SIN wave, then amplified to AC75Vrm bell signal by the amplitude between +160V and -100V of voltage (Mainly
+30Vdc) produced by SW power supply. When the Bell signal is not needed, bell signal voltage generating circuit can be turned
off by transmitting H signal from P21 port (BELL CNT) of ASIC to reduce the power consumption.
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KX-TDA6174XJ / KX-TDA6174X
7.13. BELL SIGNAL TRANSMISSION
AC 75Vrms bell signal generated onboard is transmitted to the individual port, then control the bell ON/OFF by making a bell relay
in each port (Bell signal ON) and by breaking it (Bell signal OFF). The 16 ports do not ring simultaneously. They are divided into
4 layers to control ON/OFF. They are divided in to following 4 groups (The ports in the same group ring simultaneously.): "1, 5, 9,
13", "2, 6, 10, 14", "3, 7, 11, 15" and "4, 8, 12, 16".
in each port (Bell signal ON) and by breaking it (Bell signal OFF). The 16 ports do not ring simultaneously. They are divided into
4 layers to control ON/OFF. They are divided in to following 4 groups (The ports in the same group ring simultaneously.): "1, 5, 9,
13", "2, 6, 10, 14", "3, 7, 11, 15" and "4, 8, 12, 16".
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7.14. POWER SUPPLY VOLTAGE GENERATOR
The input from the main power supply is in 3 voltage levels: +15V, +30V, +40V. Since the voltage levels: +15V, +5V, +3.3V, +40V,
+160V, +100V, -100V and AC 75Vrms are required onboard, voltage levels are generated onboard as written below.
+160V, +100V, -100V and AC 75Vrms are required onboard, voltage levels are generated onboard as written below.
A DC-DC converter that generates +3.3V and +5V from 15V input from the main power supply.It consists of a circuit that steps
down the voltage from +15V to +3.3V by the switching power supply of IC10, Q13 and L10, and a circuit that steps down the voltage
from +15V to +5V by the switching power supply of IC7, Q12 and L7.As protective circuits, IP4 that protects from +3.3V short circuit,
IP5 that protects from +5V short circuit, and an overvoltage protection that breaks IP1 by turning on FET in Q14 when a rise in
voltage of +3.3V/+5V is detected.
down the voltage from +15V to +3.3V by the switching power supply of IC10, Q13 and L10, and a circuit that steps down the voltage
from +15V to +5V by the switching power supply of IC7, Q12 and L7.As protective circuits, IP4 that protects from +3.3V short circuit,
IP5 that protects from +5V short circuit, and an overvoltage protection that breaks IP1 by turning on FET in Q14 when a rise in
voltage of +3.3V/+5V is detected.
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KX-TDA6174XJ / KX-TDA6174X
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