Speco Technologies VM-1201 - Manual (Page 8)

This section describes each functional block of the monitor.
2.1 Main Power Supply Block
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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
filtering R906, C909.
Energy storing and transferring ：Power transformer T901.
Power driving ：Power MOS transistor Q901.
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