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11
KX-DT543/KX-DT543-B/KX-DT546/KX-DT546-B
3. Headset Call
Transmitting signal is input from headset microphone
input to IC410-pin 26
amplified by a built-in analog amplifier of
IC410
A/D conversion, Gain adjustment and echo cancel by a built-in DSP of IC410.
Receiving signal is sent by data from PBX
Gain adjustment and D/A conversion by a built-in DSP of IC410
amplified by
a built-in analog amplifier of IC410
output from IC410-pin 42
output to headset speaker.
4.2.6.
ASIC (IC300)
IC300 controls Data Communication (refer to chapter 4.2.3) between PBX and proprietary telephone, and DXDP Communication
(refer to chapter 4.2.4) .
IC410 controls IC300 with SPI (Serial peripheral interface).
PCM signal (encoded audio signal) is exhanged between IC300 and IC410.
IC410
C571
R566
AGND
AGND
AGND
AGND
AGND
MICBIAS
L461
L462
R569
C576
C577
C578
C579
C581
R570
C580
DG
DCX81
26
LIN0
42
LOUT
CN400
2
CN160
13
3
HESMIN
HESSPOUT
12
Main PCB
IC150
ASIC2
Ope PCB
JK160
1
4
2
3
5
AGND
AGND
AGND
C165
C167
C166
AGND HEADGND
HEADGND HEADGND
HEADGND HEADGND HEADGND
R160
R161
C164
HEADGND
AGND
HEADGND
C159
C158
D162
L160
D161
L161
L162
D163
L163
C168
C169
6
GKEYIN0