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10
KX-TG6451RUT/KX-TGA641RUT
4.2.3.
Telephone Line Interface
Function
• Bell signal detection
• CLIP signal detection
• ON/OFF hook and pulse dial circuit
• CLIP signal detection
• ON/OFF hook and pulse dial circuit
Bell & CLIP (Calling Line Identification Presentation: Caller ID) signal detection:
In standby mode,Q111/Q115 is open to cut the DC Loop current and decrease the ring load.
When ringing voltage appears at the TIP and RING, AC ring voltages transferred as followings;
CLIP signal detection
When ringing voltage appears at the TIP and RING, AC ring voltages transferred as followings;
CLIP signal detection
TIP
→ C181 → R182 → R185 → IC501(26)(BBIC-CIDINn)
RING
→ C191 → R192 → R195 → IC501(27)(BBIC-CIDINp)
Bell signal detection
TIP
→ C181 → R182 → C184 → R186 → C187 → IC501(30)(BBIC-RINGING)
When power line failure (Because this case is no power to IC501)
TIP
TIP
→ C164 → D161(2) → D161(1) → IC101(1:5) → R167 → RINGERP
RING
← D161(3) ← D161(4) ← Q162(c:e) ← IC101(2:8) ← RINGERM
ON/OFF hook circuit
ON hook:
Q111/Q115 is open to cut the DC loop current and voice signal, caused by the following control:
Hook switch (between hook2-4 and hook2-6) is opened and IC501(29)(Hook CTRL) is Low, (and Q114 is open), then Q112 is
OFF,so Q111/115 is OPEN
OFF hook:
Q111/Q115 is ON to make the DC loop current and be possible to transfer voice signal, caused by the following control:
Hook switch (between hook2-4 and hook2-6) make and IC501(29)(Hook CTRL) is High. (and Q114 is open), then Q112 is ON.
Q111/Q115 is open to cut the DC loop current and voice signal, caused by the following control:
Hook switch (between hook2-4 and hook2-6) is opened and IC501(29)(Hook CTRL) is Low, (and Q114 is open), then Q112 is
OFF,so Q111/115 is OPEN
OFF hook:
Q111/Q115 is ON to make the DC loop current and be possible to transfer voice signal, caused by the following control:
Hook switch (between hook2-4 and hook2-6) make and IC501(29)(Hook CTRL) is High. (and Q114 is open), then Q112 is ON.
4.2.4.
Audio signal Flow (Out line)
The audio signal from Mic (for SP-phone and Corded Handset) is converted from Analog to digital in TAM companion IC(IC201),
then is transfered to BBIC(IC501) through PCM interface.
In BBIC(IC501), these data is converted to Analog, then send out tel line through tel line interface.
On the other hand, the audio signal from tel line is converted from Analog to digital in BBIC(IC501), then is transfered to TAM
companion IC(IC201) through PCM interface.
In TAM companion IC(IC201) ,these data is converted to Analog, then sound out from speaker.
Refer to the fig.2.
then is transfered to BBIC(IC501) through PCM interface.
In BBIC(IC501), these data is converted to Analog, then send out tel line through tel line interface.
On the other hand, the audio signal from tel line is converted from Analog to digital in BBIC(IC501), then is transfered to TAM
companion IC(IC201) through PCM interface.
In TAM companion IC(IC201) ,these data is converted to Analog, then sound out from speaker.
Refer to the fig.2.
<Fig.2>
4.2.5.
RF cuircuit
BBIC(IC501) inclueds the RF transceiver circuit. (LNA,Mixer, IF filter, modulator/Demodulator,PLL, VCO etc).
This RF transceiver is interfaced with Power-AMP(IC801) and Antenna circuit.
This RF transceiver is interfaced with Power-AMP(IC801) and Antenna circuit.
4.2.6.
Pulse Dialling
During pulse dialling the hookswitch (Q3, Q4) is used to generate the pulses using the HOOK control signal, which is set high
during pulses. To force the line impedance low during the “pause” intervals between dial pulses, the PULSE_DIAL signal turns
on Q2.
during pulses. To force the line impedance low during the “pause” intervals between dial pulses, the PULSE_DIAL signal turns
on Q2.
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