Sharp R-8R51 - Page 24

A ERSILW)
2 8R51{B1
TOUCH CONTROL PANEL ASSEMBLY
OUTLINE OF TOUCH CONTROL PANEL
The
touch
cantrol
section
consists
of
the
isllewing
_4)..
ACL.
Circuit...
;
tMItS
as
Shown
in
the
touch
control
panel
circuit.
Acircuit
to
generate
signals
resetting
the
LSI
to
the
_ initial state when power is supplied.
.
7.
!
(2)
Controi
Unit
ae
eee
5)
Buzzer
Circuit
_
The
buzzer
is
responsive
to
signals
from
the
LSI
to
emit, noticing
sounds.
ney
touch
sound
and
The principal functions of these units and the signals
communicated among them are explained below.
Key Unit completion sound). -
—Fhe-key-unitts- composed of a matrix, signals generate $$
in
the
LS!
are
sent
to
the
key
unit
through
-
6)
Temperature
Measurement
Circuit(1}:
Oven
PO1,P04,P07,P11
and
P26.
.
.,
...
Thé
temperature
in
the
oven
cavity
is
sénséd
by
the
When
a
key
pad
is
touched,
a
signal
is
completed’
thermistor.
The
vatiation
of
resistance
according
through the key unit and passed back to the LSI
through RO-R3 to perform the function that was re-
quested.
to sensed temperature is detected by the temper-
ature measurement circuit and the result applied to
LSI. The result. of detecting is given to LSI con-
Control Unit trolling the relay and display.
Control
unit
consists
of
LSI,
power
source
circuit,
ele
synchronizing
signal
circuit,
ACL
circuit,
buzzer
circuit,
ee
temperature
measurement
circuit
and
indicator
circuit.
7)
Door
Sensing
Switch
CODE
RETE)
A
switch
to “tell”
the
LSI if
the
door
is
open
or
1)
LSI
closed.
This
LSI
contro!s
the
temperature
measurement
signal.
key
strobe
signal,
relay
driving
signal
for
8)
Relay
Circuit
.
oven
function
and
indicator
signal.
To
drive
the
magnetron,
convection
heater,
grill
("RD976A1U)
;
heater,
fan
motor,
convection
motor, damper
motor,
2)
Power
Source
Circuit
turntable
motor,
rotisserie
motor,
surge
relay
and
This
circuit
generates
voltages
(VA: -15V,
VC: -5V,
light
the
oven lamp.
VF1: -25V,
VF2:
-28V
and
Vp:
-34V)
necessary
in
the control
unit.
__
nea
ths
9)
Indicator
Circuit
—
3)
Synchronizing
Signal
Circuit
Indicator
element
is
a Fluorescent
Display.
The power source synchronizing signal is avatlable
in order to compose a basic standard time in the .
clock
creat
cathode,
a
grid
and
an
anode.
Usually,
the
cathode
{t accompanies a very small error because it works of a Fluorescent Display is directly heated and the
on commercial frequency. filament serves as cathode.
(ROS18A2U) The Fluorescent Display has 6-digits, 17-segments.
(RD91DA2U}
Basically, a Fluorescent Display is triode having a
22