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touch control panel circuit.
among them are explained below.
sent to the key unit through P30 - P37. When a key pad is touched, a
signal is completed through the key unit and passed back to the LSI
through P14 - P17 to perform the function that was requested.
light circuit, synchronizing signal circuit, reset circuit, buzzer circuit,
and indicator circuit.
for oven function and indicator signal.
pose a basic standard time in the clock circuit. It accompanies a
very small error because it works on commercial frequency.
when power is supplied.
sounds (key touch sound and completion sound).
ment, and light the oven lamp.
trodes using a Liquid Crystal Display.
dling these parts, the following precautions should be strictly followed.
CMOS LSI have extremely high impedance at its input and output ter-
minals. For this reason, it is easily influenced by the surrounding high
voltage power source, static electricity charge in clothes, etc., and
sometimes it is not fully protected by the built-in protection circuit.
panel of the microwave oven and the precautions you must take when
doing so. To perform the servicing, power to the touch control panel is
available either from the power line of the oven itself or from an exter-
nal power source.
PRESENTS A HAZARD.
separated. For those models, check and repair all the controls
(sensor-related ones included) of the touch control panel while
keeping it connected to the oven.
be separated from each other. For those models, therefore, it is
possible to check and repair the controls of the touch control
panel while keeping it apart from the oven proper; in this case
you must short both ends of the door sensing switch (on PWB)
of the touch control panel with a jumper, which brings about an
operational state that is equivalent to the oven door being
short both ends of the door sensing switch (on PWB) of the touch
control panel, which activates an operational state that is equiva-
lent to the oven door being closed. Connect an external power
source to the power input terminal of the touch control panel, then it
is possible to check and repair the controls of the touch control