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Electric power circuit is composed of Sub PWB which reduces noise and SMPS (Switching Mode Power Supply). SMPS
consists of rectifier (BD1,CE1) which converts AC voltage to DC voltage, switching parts (IC11) which switches the rectified
DC voltage, trans parts which transmit, energy from the primary to the secondary, secondary electric power which supplies
electricity to MICOM and IC, and feed back parts (IC10, IC12) which feed back to the primary trans in order to maintain
constant secondary voltage.

• High voltage (DC 310V) is maintained at electric power terminals. Unplug power cord from the outlet and wait for

three minutes before taking measures if power circuit is wrong. Be care of electric shock.

This circuit is for clock generation for synchronizing transmission and reception of information of internal logic element of
IC1 (MICOM). Use standard oscillation when oscillation spec is changed as time calculated by IC1 changes or can not work. 

This is the circuit by which all functions start from the initial conditions by initializing many parts such as RAM in the MICOM
when electricity is first on or electricity is reapplied to MICOM by momentary power cut. Low voltage is applied to the reset
terminal of MICOM for 10ms when electricity is first applied. Reset terminal is 5 voltage for general operation. (MICOM does
not operate when reset IC is fault.)

- 36 -

+

+

+

POWER

CON1

IC1

(MICOM)

TRANS 10,11

R1

R4

R3
4.7K

D3
FR104

F2

1K

R5

4.3/1W

4

5

4

7.8

1

2

2

5

3

4

F1

3

2

BD1

D3SBA60

R11

560K

1/2W

D2

FR104

D1

FR107

D4

FR302

1.5K
R8

R6 1.8K

IC10

TLP721

IC12

KIA431

CC7

102

/50V

R10

2.4K

R7

9.1KF

R9

15K

CN5

223/100

CE2

47uF

/50V

CE3

2200uF

/25V

CE1

82uF

/450V

CN3

473

/630V

R2

56K
/2W

CC1

102

330K/1W

VA1

SVC471

D14A

VDD
Varef

6
5
4
3
2
1

IC11

STR

F6553

CC5

221/2KV

CC6

221/2KV

7805

IC2

CC2

104

CC3

104

CC4

104

64

55

32

54

26

TEST

VASS

VSS

CC29

104

CE5

220uF

/16V

CE6

220uF

/16V

+

+

IC 1

(MICOM)

XOUT

XIN

30

R67

1M

OSC1

CST4.00MGW

31

KIA7042P

IC1

(MICOM)

CC11

104

2

R16

100

R18

1K

1

IC3

RESET

29

R17

4.7K

+

CE11

10uF

/50V

CC12

104

The purpose of this circuit is to judge whether the function control buttons in the control display are pressed or not and to
light LED (LED MODULE) for displaying each function.  The driving type is SCAN. 

- 45 -

13

12

14

11

10

9

8

6

7

5

4

3

2

1

IC1

(MICOM)

P20

(INT5/STOP)

P17

P16

P15

(TC2)

P14

(PPG)

P13

(DVO)

P12

(INT2/TC1)

P11

(INT1)

P10

(INT0)

P07

P06

P22

(XTOUT)

P70

(AIN10)

15

28

16

17

18

19

20

21

22

23

24

25

1

R39

RF5
10KF

2K

9

1

18

2

17

3

16

4

15

5

14

2

15

3

14

4

13

5

12

6

11

7

8

16

1

10

R32

R34

2K

R35

100

CC13

102

R33

2K

IC7-2

130.1/2W

R31

130.1/2W

R30

130.1/2W

R29

360.1/2W

R28

360.1/2W

R27

360.1/2W

10

9

IC6

TD62783AP

IC7-1

KID65003AP

CC28

104

SW103

IN4148

X

4

SW102

D108

SW104

D109

SW101

D107

D106

LED

MODULE

12

11

10

Q

W

Q

W

M

N

X

P

U

V

N

K

P

U

V

8

A

A

R

S

T

9

L

K

J

H

G

7

6

5

4

3

2

1

IN4004

X

5

D105

D104

D103

D102

D101

CON101

CON6

RT–SENSOR

B

C

D

E

F

R36

4.7K

2

1

3

4

5

6

8

7

9

10

11

12

13

N

P

F
E
D
C
B
A

L
K
J

H
G
A

Q

R

S

T

U

V

W

M

X

Freezer

Temp

Control

Refrigerator

Temp

Control

Power

Freezer

Crushed/Water/Cube

• The tolerance of sensor resistance is 

±

5%.

• Be sure to measure the sensor resistance after keeping the sensor more than 3 minutes at a measuring temperature. (It

needs delay due to sense speed.)

• Use a digital tester if possible, because a measuring temperature is too high for an analogue tester.

• Measure the resistance with a digital tester after disconnecting CON 8 of MAIN PWB ASSY. part as there is no connector

in refrigerator sensor 1 and 2

• Measure the resistance of a freezer sensor with a digital tester after disconnecting CON 7 of MAIN PWB ASSY. part.  

- 46 -

-20

°

C

22.3k

Ω

77k

Ω

-15

°

C

16.9

60k

Ω

-15

°

C

13.0k

Ω

47.3k

Ω

-5

°

C

10.1k

Ω

38.4k

Ω

0

°

C

7.8k

Ω

30k

Ω

+5

°

C

6.2k

Ω

24.1k

Ω

+10

°

C

4.9k

Ω

19.5k

Ω

+15

°

C

3.9k

Ω

15.9k

Ω

+20

°

C

3.1k

Ω

13k

Ω

+25

°

C

2.5k

Ω

11k

Ω

+30

°

C

2.0k

Ω

8.9k

Ω

+40

°

C

1.4k

Ω

6.2k

Ω

+50

°

C

0.8k

Ω

4.3k

Ω

* Freezer fan motor stops operation when freezer or refrigerator door is open. But it works when refrigerator door is closed.

*  A  B  C  D  of freezer and refrigerator door switch are switch ends which detect door opening and are connected to door

opening sensor circuit.

* Home Bar door switch is connected to the refrigerator door switch  C  D  in parallel. It can detect if one of these doors is

open.

- 37 -

Freezer 

COMP Machine

Defrost

AC Convertible

Refrigerator

Electronic

Chilled Drawer

Fan Motor

Load Types

Room Fan

Heater

Relay

LAMP

Single

Duct Heater

High

Standard

Motor Damper

Speed Speed

Measuring Point(IC 4)

No.10

No.11

No.12

No.13

No.14

No.15

No.16 IC5-10

Conditions

ON

Below 1V

OFF

12V

MACHINE ROOM

DEFROST

HOME BAR

DOOR

SWITCH

R-DOOR SWITCH

(VEGETABLE DUCT)

F-DOOR SWITCH