Analog Circuit - Panasonic KX-T7630 Service Manual

10.8. ANALOG CIRCUIT

This circuit performs the setting of the call path/vol. adjustment in each call mode by DSP built in
IC5.
The audio gain of each call is determined by download data from PBX.
- IC5 sends each audio data to IC4 by PCM interface.
- IC5 receives each audio data from IC4 by PCM interface.
1. Handset Call
Transmitting signal is inputted from handset microphone and
amplified by IC4 built-in Amp
PCM data
Transmitting signal inputted from handset microphone is
controlled by transmission switching SW IC7 as below.
IC3-pin 52 L : Handset Call
(IC3-pin 52 H : Headset Call)
Receiving signal inputted from PBX is
of IC5 D/A conversion after the input to IC4 in PCM data
built-in Amp output
2. Headset Call
Transmitting signal is inputted from headset microphone and
amplified by IC4 built-in Amp
Gain adjustment by DSP of IC5
outputted from IC5 built-in Amp to handset.
A/D conversion
Gain adjustment by DSP
A/D conversion
20
inputted to IC5 in
then sent to PBX.
inputted to IC5 in
IC4