Samsung RL-33EBMS CIRCUIT DETAILS

6. CIRCUIT DETAILS

6-1 Power Supply Part

7

Power supply

Vcc (DC 5V)

Vcc (DC 12V)

5

D101-104

In4007

C105

C105

104

104

C101

1000uF

C801

104

Applied circuit

Chip peripheral circuit and sensor

Control voltage of the display and relay

C802

104

The AC input voltage will be stepped down by the transformer and be converted into the DC voltage
by the rectifying circuit (D101-104). The 1000F/35V wave filter capacitor will be used to filter out the
residue AC voltage and the manostat 7812 is used to output the steady 12V DC voltage that will be
used as the control voltage of the relay and display. The 12V DC voltage will be regulated by the
manostat 7805 to output the steady 5V voltage, which will be used as the output voltage of the chip
peripheral circuit and various signals (sensor, switch) .

6-2 Reset Circuit Part

Vcc

I

C203

104

Ic02

5195A

G

O

C202

104

18

21

RESET

VSS/ASS

The reset circuit part enables the system program to return the system that meets power trouble
or abrupt power-off to the initial state by the memory of the core chip. At the very beginning of
the power-on, the reset chip voltage is LV, and becomes HV after normal operation.

17

6-3 Crystal Viberation Part

19 Xin

Crystal Viberation

4MHz

20 Xont

This circuit is used for the geneation of the resonant clock by receiving and sending the logic
element information within the core chip. The time on the clock will play the role of time base.
The resonance circuit must apply the rated criteria of each element as specification deviation
will change the core chip time and disable the running.

6-4 Sensor Part

Freeze Sensor

Main evaporator
sensor

Refrigerating
sensor

Magnetic switch

Door switch

1

2

3

4

5

6

CN30

WHT

Vcc(5V)

R303 10K -F

R303 10K -F

R305 10K -F

R401 4.7K -F

R403 4.7K

R307 10K-F

EXT-S/S

R302 1K

R304 1K

R306 1K

R402 10K

R404 10K

R308 1K

C301

104

C302

104

C303

104

C401

104

C402

104

C304

104

26

27

28

29

Core chip

41

30

The sensor and the resistance in F precision are respectively connected to Earthing and DC5V.

The resistance value that varies with the temperature are converted into the corresponding voltage.

Test the voltage at the A/D transition interface of the core chip to determine the temperature.

18