Dell 320-7459 - S1909WXF - 19" LCD Monitor, Руководство по обслуживанию

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Service Manual
8
2.2 Power PWM circuit
2.2.1) Block diagram :( fig.4)
Fig.4
2.2.2) AC Input and EMI Filter :( fig.5)
fig.5
CN850 is a connector for connecting AC Power. F850 is a fuse to protect all the circuit AC.
Input voltage is from 90V to 264V. R850 and R851 are joined between two inputting main circuit
to prevent man from shock. L851 is used to clear up low frequency wave. C850 and C851 are
used to discharge the waves that L851 produced. High frequency waves are damped by C852
and C853.
2.2.3) High Voltage to Low Voltage Control Circuit :( fig.6)
EMI Filter Rectifier and
filter Isolation power
transformer Rectifier and filter Inverter circuit
PWM controller
Switching element
Feedback Isolation
Rectifier and filter
LDO regulator