Samsung SR-L676EV User manual

REFRIGERATOR
Model : SR-L676EV
SR-L678EV
SR-L626EV
SR-L628EV
REFRIGERATOR CONTENTS
1. Precautions
2. Product Specifications
3. Electrical Part Specifications & Standard
4. Circuit Diagram
5. Functions & Operating Instruction
6. Circuit Descriptions
7. Troubleshooting
8. Parts List
9. Disassembly & Assembly
10. PCB Circuit Diagram
11. PCB Parts List
12. Specifications of Main Components
SR-L676EV
SR-L678EV
SR-L626EV
SR-L628EV
GREEN

2 Samsung Electronics
2. Product Specifications
3. Electrical part specifications & standard
SR-L628EV SR-L678EV SR-L626EV SR-676EV
(LMF(Freezer/Refrigerator) 2 Door)
(4-STAR)
Electronic control
HFC-134a(160gr)
CYCLO-PENTANE
CYCLO-PENTANE
A.B.S
A.B.S
114Kg 113Kg
Yes
171(6.04) 192(6.78)
345(12.18) 376(13.28)
516(18.22) 568(20.06)
820X715X1790 (mm) (SR-L626(8)EV)
820X765X1790 (mm) (SR-L676(8)EV)
No
171(6.04) 192(6.78)
351(12.39) 382(13.49)
522(18.43) 574(20.27)
Model
Type
Freezer performance
Temperature control
Water dispenser
Freezer
Refrigerator
Total
Net Capacity
l/(ft3)
Cabinet insulation
Door insulation
Cabinet
Door
Foam
Liner
Net weight
Net dimension
(WXDXH)
Refrigerant
ITEM
Model
Input Source
STANDARD
SR-L626/628EV SR-L626(8/676(8)EV SR-L676/678EV
220V 240V
SK182H-L2U SK182Q-L2U
RSCR
115V 127V
SK182E-L2W SK182P-L2 W
CSR RSCR
Freon α-15(ESTER)
Split Fin Type
Split Fin Type
Forced & Natural Convection Type
Molecular Sieve XH-9
ID0.85XL2500 3.79kg/cm2
BSBN(Brass screw)
250V/0.5A
220V 240V
SK190H-L2U SK190Q-L2U
Condenser
Dryer
Capillary tube
Earth screw
Door switch
Model
Starting type
Oil charge
Freezer
Refrigerator
Compressor
Evaporator
Refrigeration Cycle

Samsung Electronics 3
ITEM STANDARD
Freezer:6 – 16hr/Refrigerator:12 – 32hr
10min±2min
4hr±10min
502AT
502AT
502AT
502AT
502AT
200W (115V, 127V, 220V, 240V)
130W (115V, 127V, 220V, 240V)
2W (115V, 127V, 220V, 240V)
Type
F-Sensor
Mode
High
Mid
Low
Mode
High
Mid
Low
Defrost cycle
Rest time
First cycle
ON(˚C)
–20˚C
–16.5˚C
–14˚C
ON(˚C)
–0.5˚C
3.5˚C
6.5˚C
OFF(˚C)
–22˚C
–18.5˚C
–16˚C
OFF(˚C)
–1.5˚C
2.5˚C
5.5˚C
Type
R-Sensor
Defrosting
Freezer-Sensor
Refrigerator-Sensor
FRE EVAP-Sensor
REF EVAP-Sensor
Room TEMP-Sensor
FRE Defrost-Heater
REF Defrost-Heater
Lamp-Heater
FRE Defrost-Fuse
REF Defrost-Fuse 250V 10A 72 ± 4˚C 250V 10A 72 ± 4˚C
VOLTAGE 115V 127V 220V (626/628EV) 220V (676/678EV) 240V
CONDENSER
OVER-LOAD
PROTECTOR
STARTING-
RELAY
MOTOR-FAN
LAMP
MOTOR-GEARED
STARTING
RUNNING
MODEL
ON TEMP .
OFF TEMP .
MODEL
RESIST ANCE
FRE. REF .
CIRCUIT-MOTOR
FRE.
REF.
REF.
125VAC/125 µF
250VAC/12 µF
4TM445SHBYY-53
135˚C
PTHAS-T100M200B
IS3208TMDA-4
IS3208-SCF6A
125VAC/125 µF
250VAC/12 µF
4TM444NHBYY-53
120˚C
PTHAS-T100M200B
IS3208TMDA-8
IS3208-SCO6A
350VAC/5 µF
4TM308PHBYY-53
125˚C
PTHAS-T220M350D
350VAC/5 µF
4TM314RHBYY-53
130˚C
PTHAS-T220M350D
350VAC/5 µF
4TM232SHBYY-53
135˚C
PTHAS-T330M385D
OSRAM DEULX S/E IIW
10W± 20% 22W±20% 33W±20%
IS3208TMDA-2A
IS3208-SCF7A
IS3208TMDA-6
IS3208-SCL5A
110V~130V/15W 220V/15W 240V/15W
M2BC18AR02 M2LC18AR02
690˚C
Temperature
Electrical parts
Fuse Heater FreezerRefrigerator
Sensor

6 Samsung Electronics
•5-1 Product Dimension
5. Function & Operating Instruction
MODEL
SRG-L678EV
SRG-L676EV
SR-L628EV
SR-L626EV
A
1750.0
1750.0
1750.0
1750.0
B
994.5
994.5
994.5
994.5
C
1509.7
1509.7
1459.7
1459.7
D
755
755
715
715
E
667
667
627
627
Remarks
"X"
"Y"
"X"
"Y"
"X"
"Y"
10
40
64
10
673.5
8
A
B
77 11 E10
C
D
820

Samsung Electronics 7
5-2 Part Name & Disassembly
• Chilled Compartment
disassembly
1. Pull it out by following
the arrow.
• Top tray disassembly
Pull it forward.
Take out food stuffs and
pull it out by following
the arrow.
Take out the water
bottle with the bottom
latch pressed.
• Tray disassembly
Pull it out by following
the arrow.
• Ice compartment • Vegetable compartment • Freezing compartment
2. Bend the cover and
take it out.
①
②
••
•
•
•
•
•
•

8 Samsung Electronics
5-3 Circulation of Refrigerant (H.M CYCLE)
Compressor →Sub condenser →Cluster pipe →Hot pipe →Dryer →Capillary tube
→R-Evaporator →F-Evaporator →Accumulator →Suction pipe →Compressor
ACCUMULATOR
F-EVAPORATOR
CAPILLARY
TUBE
R-EVAPORATOR
SUB CONDENSER
SUCTION PIPE DRYER
COMP.
SIDE CLUSTER PIPE
HOT PIPE

Samsung Electronics 9
5-4 Cool Air Circulation
R-FAN
MOTOR
R-EVAPORATOR
F-FAN
MOTOR
F-EVAPORATOR
OUTPUT AIR
SUCTION AIR
SUCTION AIR

10 Samsung Electronics
A. Temperature control in the freezing compartment
1) Select the 5 STEPS of ‘MED’–‘MED · HIGH’–‘ HIGH’–‘LOW’–‘LOW · MED’ with one button.
2) When-ever the temperature control button of freezer is pressed, it continues to light from “MED”
to “LOW · MED”.
3) When power turns on “MED” is automatically selected.
Category
Indicator Lamp
Reference Temp.
Initial power on
MED
–17.5˚C –19.5˚C
MED·HIGH
Pressed once
–21˚C
HIGH
Pressed twice
–15˚C
LOW
Pressed 3 times
–16.5˚C
LOW·MED
Pressed 4 times Remark
SR-L628/678EV
SR-L626/676EV
1. Temperature Control Functions
QUICK HIGH …. FREEZER …. LOW LOW ….REFRIGERATOR …. HIGH QUICK
ALM
HIGH
HUMI
QUICK FREEZER ALARM REFRIGERATOR QUICK
X-FLOW
QUICK FREEZER TEMP.CONTROL REFRIGERATOR QUICK
QUICK HIGH …. FREEZER …. LOW
ALM
HIGH
HUMI
X-FLOW
LOW ….REFRIGERATOR …. HIGH QUICK

Samsung Electronics 11
B. Temperature control in the refrigeration compartment
1) Select the 5 stages of ‘MED’–‘MED · HIGH’–‘HIGH’–‘LOW’–‘LOW · MED’ with a button.
2) Whenever the temperature control button of refrigerator is pressed, it continues of light from
‘MED’ to ‘LOW · MED’.
3) When power turns on “MED” is automatically selected.
C. Power freezing and power refrigeration function
• It is selected by the special power freezing · refrigeration button.
• Whenever the power freezing · refrigeration button is pressed, it repeats turning on and off.
• When power turns on at first, it is selected to off automatically.
• When the power freezing · refrigeration button is selected, the temperatures of freezer and
refrigerator do not change. But, the temperatures can be set again after it is selected.
1) Power Freezing Function
① If power freezing is selected, COMP and F-FAN operate for 2 and 30 hours.(In 1 minute after
selection)
② If power freezing function finishes, power freezing lamp turns off.
③ If power freezing function is selected, refrigerator is controlled by the fixed notch.
2) Power Refrigeration Function
① If it is selected, it continues until COMP and R-FANreaches to –4˚C.
② The power refrigeration finishes if COMP and R-FAN does not reach –4˚C even though 2 and
30 hour operation.
③ If it is selected, refrigerator is controlled by the fixed notch.
3) When the power freezing · refrigeration are selected simultaneously
① Each function is carried out at the same time.
Category
Indicator Lamp
Reference Temp.
Initial power on
MED
3˚C 1˚C
MED·HIGH
Pressed once
–1˚C
HIGH
Pressed twice
6˚C
LOW
Pressed 3 times
4.5˚C
LOW·MED
Pressed 4 times Remark

12 Samsung Electronics
2. Alarm function
3. Defrosting function
A. Button touch(Ding-Dong Sound)
1) When each button on the control panel is pressed, the beep sounds to confirul the key input.
2) The beep does not sound if wrong-touch.
B. Door open(Ding-Dong Sound)
1) When the door of either freezer of refrigerator is open for more than 2 minutes, the alarm rings.
2) The alarm rings for 10 seconds every one minute. When the door closes, the alarm goes off
immediately.
3) Door open alarm rings when the display button is selected. But door open alarm stops
immediately if the button is released.
4) If the alarm is selected by the button, the alarm rings regularly.
5) Alarm by the alarm button includes only door open.
6) Model SR-L676EV, SR-L626EV follows the above alarm procedure without alarm select button.
C. Forced starting · Forced defrosting (beep sound)
1) If the forced starting · forced defrosting are selected the beep tone sounds.
2) When forced starting, the beep sounds until being completed(24 hours) or released.
3) When forced defrosting, the beep sounds until being completed(including pause) or released.
A. Quick defrosting function
1) When power turns on at first, the first defrosting is carried out after compressor operates for 4
hours.
B. Standard defrosting function
1) Defrosting is divided into freezer defrosting, refrigerator defrosting and natural defrosting. The
defrosting of freezer and refrigerator is determined by the operation time of compressor.
2) Defrosting interval can vary from 6~32 hours.
C. Natural defrosting of Refrigerator
1) Natural defrosting is carried out if the compressor turns off and fan keeps on for some period.

Samsung Electronics 13
A. Forced starting function
1) The test functions are designed for PCB, product test, process inspection and service activities.
2) The test switch is on the main PCB and when pressed once, it immediately works cooling without
comp delay.
3) If the forced starting is selected, freezer and refrigerator notches are selected to “HIGH” and
“HIGH”· MED”. Comp and F-Fan are controlled by pull-down and R-Fan is controlled by “HIGH
· MED” notch.
4) The pull-down function of forced starting maintains for 24 hours and it returns to normal
operation after defrosting(F, R) is automatically carried out.
5) During forced starting, all button inputs are available. Forced starting can be released when
power turns on after off or by the test release mode.
6) During forced starting, the beep continues to sound (0.25 sec. ON/0.75 sec OFF) until defrosting
is completed.
B. Forced defrosting function
1) If the test button is pressed once during the forced starting, refrigerator is defrosted forcedly.
2) If it is pressed twice, freezer and refrigerator carry out defrosting at the same time.
3) When the forced defrosting is carried out, the forced starting is released and returns to normal
operation.
4) When the forced defrosting is carried out, the notches of freezer and refrigerator maintains the
notch fixed prior to forced starting.
C. Test mode release
1) If the test button is pressed twice during forced defrosting, the forced defrosting is canceled and
returns to normal operation.
2) If the test release mode is selected, the buzzer will stop.
4. Test function

14 Samsung Electronics
5. Self-diagnosis function
A. Self-diagnosis function with initial power on
1) If the power is supplied to refrigerator at first, all displays are on and self-diagnosis function is
carried out.
2) If there is no defect on MICOM, display returns to the initial normal mode(“Med”–“HIGH
humidity”–“Alarm”).
3) If there is defect, the televant display lights off with the sound of the beep.
4) Self-diagnosis error indicator might disappear when defect is repaired or self-diagnosis function
is released.
5) If defect is repaired, display returns to normal mode.
6) Self-diagnosis function is canceled when “power freezing” button and “power refrigeration”
button are pressed for 5 seconds at the same time. Display returns to normal mode.
B. Self-diagnosis function during normal operation
1) Press “power freezing” button and “power refrigeration” button for 5 seconds at the same time
during normal operation.
2) The temperature LEDs of freezer and refrigerator repeats 1 second on/off 3 times.
3) If any button is not pressed until the temperature LED repeats on/off 3 times, self-diagnosis
function is carried out. If there is no defect, it returns to normal mode.
4) If there is defect, the corresponding display will light up and buzzer will beep.
5) Self-diagnosis error indicator works for 30 seconds and returns to normal mode regardless of
defect correction.
6) Key input is not available during self-diagnosis function.
7) When there is defect, the corresponding display is shown as initial power on.

Samsung Electronics 15
No
1
2
3
4
5
6
7
Symptom
• R-room left sensor housing
disconnection.
• Faulty connection.
• Wire open or short.
• Faulty sensor.
• R-room left right sensor
housing disconnection.
• Faulty connection.
• Wire open or short.
• Faulty sensor.
• R-room defrost sensor
housing disconnection.
• Faulty connection.
• Wire open or short.
• Faulty sensor.
• Outer sensor housing
disconnection.
• Faulty connection.
• Wire open or short.
• Faulty sensor.
• F-room sensor housing
disconnection.
• Faulty connection
• Wire open or short.
• Faulty sensor.
• R-room defrost sensor
housing disconnection.
• Faulty connection.
• Wire open or short.
• Faulty sensor.
• Faulty geared-motor
• Faulty reed-switch
housing disconnection.
• Faulty connection.
Remark
R1-Sensor temperature is
over +50˚C or below –50˚C.
R2-Sensor temperature is
over +50˚C or below –50˚C.
RD-Sensor temperature is
over +50˚C or below –50˚C.
Outer-Sensor temperature
is over +50˚C or below
–50˚C.
F-Sensor temperature is
over +50˚C or below –50˚C.
F-Sensor temperature is
over +50˚C or below –50˚C.
Square wave not detected
by reed-S/W.
Item
R1-Sensor
R2-Sensor
RD-Sensor
Air-Sensor
F-Sensor
FD-Sensor
Geared-
Motor
Display LED
Refrigerator “LOW”
Refrigerator
“LOW · Med”
Refrigerator “Med”
Freezer “LOW”
Freezer “LOW” · Med”
Freezer “Med”
Refrigerator “HIGH”
(Self-diagnosis Display Table)

16 Samsung Electronics
C. Load status display
1) When “power freezing” button and “power refrigeration” button are pressed for 5 seconds
during normal operation, it is activated by the refrigeration button while temperature setting
display repeats on/off 3 times.
2) Load which output of micom is displayed on LED.
3) Load status display maintains for 60 seconds and returns to normal operation.
No
1
2
3
4
5
6
7
8
9
10
11
Display LED
Freezer “LOW”
Freezer “LOW · Med”
Freezer “Med”
Freezer “M e d ·HIGH”
Refrigerator
“LOW · Med”
Refrigerator “Med”
Refrigerator
“Med · HIGH”
Refrigerator “HIGH”
Quick Freezing
Quick Refrigeration
High humidity
refrigeration
Display
Relevant LED ON during comp
operation
Relevant LED ON during F-FAN
operation
Relevant LED ON during freezer
defrost heater on
Relevant LED ON during freezer
bulb ON
Relevant LED ON during F-FAN
operation
Relevant LED ON during
refrigerator defrost
Relevant LED ON during
refrigerator bulb ON
Relevant LED ON during
refrigerator brade rotation
Relevant LED ON with initial
power input
Relevant LED ON when ambient
temperature is over 35˚C
Relevant LED On when ambient
temperature is below 20˚C
Item
COMP
F-FAN
Freezer defrost Heater
Freezer bulb
R-FAN
Refrigerator defrost
Heater
Refrigerator bulb
GEARED-Motor
Initial Mode
Overload
Low temp.
Refrigerator Subordinate
Mode Display
Freezer Subordinate
(Load Status Display Table)

Samsung Electronics 17
6. Option function
1) Freezer Temperature Shift (Unit ˚C)
SHIFT
Reference
-0.5
-1.0
-1.5
-2.0
-2.5
-3.0
-3.5
SHIFT
+0.5
+1.0
+1.5
+2.0
+2.5
+3.0
+3.5
+4.0
14
0
0
0
0
0
0
0
0
13
0
0
0
0
1
1
1
1
12
0
0
1
1
0
0
1
1
11
0
1
0
1
0
1
0
1
14
1
1
1
1
1
1
1
1
13
0
0
0
0
1
1
1
1
12
0
0
1
1
0
0
1
1
11
0
1
0
1
0
1
0
1
2) Refrigerator Temperature Shift (Unit ˚C)
SHIFT
Reference
-0.5
-1.0
-1.5
-2.0
-2.5
-3.0
-3.5
SHIFT
+0.5
+1.0
+1.5
+2.0
+2.5
+3.0
+3.5
+4.0
18
0
0
0
0
0
0
0
0
17
0
0
0
0
1
1
1
1
16
0
0
1
1
0
0
1
1
15
0
1
0
1
0
1
0
1
18
1
1
1
1
1
1
1
1
17
0
0
0
0
1
1
1
1
16
0
0
1
1
0
0
1
1
15
0
1
0
1
0
1
0
1
1) Method : • The temperature of the freezer and refrigerator can be compensated from +4.0 to –3.5˚C.
• Reference : Freezer (–17.5˚C)
Refrigerator(+3.0˚C)
As above table • Shift No 1, 2, 3, 4 are designed to compensate freezer temperature
(PCB D601, D602, D603, D604)
As above table • Shift No 5, 6, 7, 8 are designed to compensate refrigerator temperature
(PCB D605, D606, d607, D608)
As above table • “0” means non-diode (IN4148)
“1” means diode
❋ Temperature is compensated with power input after diode connects to the option table.

1
3
5
7
1
3
5
7
BD05-08
1N4004 X 4
FUSE2
250V 0.5A
HEAT-STICK
7812
(MC7805) 7805 (MC7805AC)
HEAT-STICK 104
(DC12V)
+12
Vcc
(DC5V)
C109
104
+C107
470uF
25V
IC03
+IC03
C103 IC02
HEAT-STICK
7812
(MC7812)
+C
1000uF
35V
ICO1 + C
470uF
25V
V12
(DC12V)
BD01-04
1N4004 X 4
L V T
CON1
WHT GRY
GRNREDBLK
BLK
BLU
C106
18 Samsung Electronics
1. Power circuit
6. Circuit Descriptions
Voltage
(DC 12V)
Vcc (DC 5V)
V12 (DC 12V)
Circuit used
Relay Operation
Power around MICOM & Sensor Detector
LED Display & S/W Detector
The input AC voltage of DC-trans secondary registers 15V at CON1 between ① ~ ③ . The rectified
voltage passed through BD05 ~ 08 becomes DC 12V through volt age regulator MC7812(IC02). The
power(DC12V) is supplied to the relay operation power block. Then, DC 5V is genetatel and supplied
to the power around micom and sensor detector through 7805(I C03).
The rectified voltage passed through BD01~04 passes through 7812(IC01). Then, DC12V is supplied to
LED display and switch detector.
+12

Samsung Electronics 19
It is designed for clock generation and time
calculation for synchronizing transmission and
reception on the logic elements inside the MICOM.
If the X-TAL specification changes, MICOM may
make an error. The standard components should be
used.
Port
Xin
Xout
Oscillating Fr equency
4.00MHz
4.00MHz
±0.5% Error
When power is supplied to MICOM, reset circuit
initializes RAM and other parts on MICOM to
initialize all programs. Reset voltage maintains
“low” for hundreds of µsec comparing to MICOM
Vcc voltage when power is input. It also maintains
“high”(5V) during normal operation. But, when Vcc
drops to 3.3V, reset port becomes “low”.
Port
Xin
Xout
Voltage
5V
5V
2. Oscillator
3. Reset Circuit
4. Door S/W Detector
KA7533 29 RESET
R201
1K
R202
10K
C202
104
C203
1µF/25V
F-DOOR S/W
R-DOOR S/W
CON06
Vcc
R401(4.7K)
R403(4.7K)
R402
R404
C401
104
C402
104
7
8
10K
10K
30P
30P
x-tal
30
31
Xin
Xout

20 Samsung Electronics
1) If door is open, door S/W contact is closed. Then MICOM receives “low” signal and detects
door open.
2) If door is closed, door S/W contact is open. Then MICOM receives “high” signal and detects
door close.
DOOR
F
R
Door Conditions
CLOSE
OPEN
CLOSE
OPEN
Door S/W Contact
OPEN
CLOSE
OPEN
CLOSE
MICOM
PIN NO
# 7
# 8
Micom Input Voltage
“LOW”
“HIGH”
“LOW”
“HIGH”
5. “V” Motor Position Detector(Reed S/W)
1) The position of “V” motor for controlling the G.A–fuzzy of the temperature in the
refrigeration room is detected by the reed switch.
2) When MICOM Pin 43 changes ‘high’ to ‘low’ by the operation of fan, MICOM detects the
position of “V” motor.
REED S/W
CON 02
7
6
5
Vcc R405
4.7K R406
10K C403
104
43

Samsung Electronics 21
6. Temperature Sensor
1) The sensor uses the characteristics of thermistor. If temperature goes higher, resistance goes
lower. On the contrary, if temperature goes lower, resistance goes higher.
2) MICOM input voltage is counted by sensor as follows.
(VCC : 5V, RTH : Sensor reisitance)
3) For the resistance information on temperature and MICOM input voltage, please refer the
conversion table. (Page. 41)
RTH
VF = X Vcc
RTH +R24
When Sensor is open
MICOM input “HIGH”
When sensor is cut off
MICOM input “LOW”
( Air Sensor)
R2-ROOM
R1-ROOM
4
3
2
1
4
3
2
1
R301
10K-F
Vcc
R303
10K (F)
Vcc R302
10K
R304
10K
60
59
THERMISTOR 1
2
3
4
1
2
3
4
R305
10K (F)
Vcc
R307
10K (F)
Vcc R306
10K
R308
10K
62
61
R309
Vcc
R310
10K 58
F-ROOM
THERMISTOR
R / DEF - SONSOR
THERMISTOR
F / DEF - SONSOR 5
65 6
10K (F)
R311
Vcc
10K (F) R312
10K 104 C306
104 C305
104 C304
104 C303
C09
104 C302
104 C301
63
"A"
P64
P63
P66
P65
P62
P67
CON2
CON3

10
9
4
3
2
1
5
6
7
8
11
10
9
4
3
2
1
5
6
7
8
11
10
9
4
3
2
1
5
6
7
8
11
X4 X5 X6
1N4148
C C-N N N-W W
C C-N N N-W W
X1 X2 X3 Alarm
X-Flow Quick FRE
Quick REF
HIGH
HUMI S/W01
S/W02
S/W03
S/W04
S/W05
1N4148
1N4148
1N4148
1N4148
KEY INPUT
4. 7 K
R04
R502
1.2K
R503
1K
18
17
16
15
14
6
9
GRID 05
GRID 04
GRID 03
GRID 02
GRID 01
IC05
IC04
1
2
3
4
5
13
10
6
5
4
3
2
1
P75
P74
P73
P72
P71
P70
P04
P03
P02
P01
P00
13
12
11
10
9
3
4
5
6
7
9
8
16
15
14
13
12
10
GND VCC
UDN2003(2803) C23
104
CON7
(XH-11P)
+12
Quick
REF
F Temp. R Temp. Quick
FRE
R501
3K
C501
3K
V
O
Grid #1 t
V
O
Grid #2 t
V
O
Grid #3 t
V
O
Grid #4 t
V
O
Grid #5 t
2mSec 8mSec
11V
22 Samsung Electronics
1) Key scan and display operation
As shown in the following waveform, MICOM pins #2 ~ #6 output are high for 2msec per 10msec.
MICOM pin #2 →#3 →#4 → #5 →#6 output repeats. The signal is output through IC05(UDN
2981A). At that time, the peak to peak voltage of square signal registers around 11V. The grid #1 ~#5
waveforms are as follows.
Refrigerator Display
Freezer Display
Letter Display
“V” Function Display
“V” Function Display
7. Key scan and display circuitry