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Net Weight
：
9 Kg
2. Theory of Operation
This section describes each functional block of the monitor.
2.1 Main Power Supply Block
AC power input
：
AC socket
Line input noise / EMI filtering
：
Line filter T902 ;
X-Cap C901, C902.
Y-Cap C903, C904, C905.
Over current protection
：
Fuse
Power on/off control
：
Power switch
AC to DC conversion and filtering
：
Diode D901, Capacitor C906
Start-up circuit
：
R914, C914.
Main switching power controller, free run oscillation, voltage feed back, switching duty control,
cycle by cycle over current protection, power MOSFET driving
：
U901-UC3842
Free run oscillation
：
R909, C910.
Voltage feed back and control
：
output voltage control R910, R911 & VR901; gain compensation
C911& R903.
Current sensing and cycle by cycle over current protection
：
Current sensing R904; Noise
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