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KX-DT543/KX-DT543-B/KX-DT546/KX-DT546-B
8.2.
ASIC1(IC300) Does Not Operate
Check the soldering.
Resolder or replace parts as needed.
Related parts: C323,C327,C324,C328,C326,
C329, L222
NO
Confirm the voltage at Pin19,30 and 43 of
IC300 (VCC33).
Is it about 3.3V?
Related parts: X301,R323,R324,C382,C383
NO
Confirm the frequency of clock signal at Pin 39 of
IC300. Is it 16.384MHz?
Refer to the waveform (4).
YES
Related parts: IC300,IC410,R333,R438,R439,
R440
NO
YES
Confirm the waveform of communication(SPI2)
between IC300 and IC410.
Refer to the waveform (9).
YES
Related parts: IC410,R423,C362
NO
YES
Confirm the waveform of reset signal at Pin1 of
IC300.
Refer to the waveform (8).
Related parts: IC300,IC410,R330,R331,
R332,R416,R441
NO
YES
Confirm the waveform of communication(PCM)
between IC300 and IC410.
Refer to the waveform (10).
Related parts: T300,C309,C302,C303,
R301,R306-311,C310,C311
NO
YES
Confirm the waveform of receiving signals
from PBX.
Refer to the waveform (11).
Related parts: T300,D301,Q302,C309,
R301-305, C302-308
NO
YES
Confirm the waveform of transmitting signals
to PBX.
Refer to the waveform (12).
END