6-3
Samsung Electronics
1. SMPS Part
Q
SMPS(Switching Mode Power Supply) Part Description
1. BRIDGE DIODE (BD71) provides full wave reification from AC input. Then smooth it with Electrolytic Condenser(C101).
Smooth voltage is similar to the results of AC input x1.414. (Ex: When AC220V is supplied, 220x1.414 = about DC310V)
2. The main power supply of ventilator is DC310V as it utilizes BLDC MOTOR.
3. PWMIC (IC01) switches smooth DC voltage, which is, in turn, induced to secondary side, so as to generate DC15V (C104) and
DC12V(C107).
4. The voltage of secondary side is decided by TURN numbers of TRANS winding. DC 15V is utilized only for CONTROL power source
of BLDC MOTOR while DC12V is used for power source of CO
2
sensor.
5. When BLDC MOTOR faulty takes place, DC 15V or DC 12V might not be generated.
6. SWITCHING DIODE of secondary side should not utilize usual rectification DIODE because SWITCHING speed of SMPS reaches
130kHz. High speed SWITCHING DIODE is required.
7. SMPS stops operation if SHORT occurs post voltage of DC12V because of FEEDBACK from DC12V.
Both ends
voltage of C101:
Approximately
DC310V
Both ends
voltage of C104:
Approximately
DC15V
Both ends
voltage of C107:
Approximately
DC12V
Both ends
voltage of C110:
Approximately
DC5V
