Acer AM501, Руководство по обслуживанию

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6.8 Power Supply
6.8.1 Degaussing CKT:
Under conditions of power on Q950 will turn on for a period of time decided by C950 and R952, during
that time period the degaussing current will flow through the degaussing coil.
6.8.2 Flyback Mode Power Conversion CKT
The flyback power conversion CKT consists of a high frequency transformer (T901), output rectifiers
and filters, and IC3842 control CKT (U901), and it uses the primary side feedback to regulate the output
voltages.
a. When Q901 turns on, the energy stores in T901, and after Q901 turns off, the energy stored in T901
will feed to secondary windings and supply to all outputs.
b. The output diodes rectify the AC voltages to DC ones and then filtered by the output capacitors to
generate DC voltages. The second LC stages attenuate the high frequency noises to get reasonable
output ripples.
c. The 3842 (U901) pin 2 senses the feedback signal comes from plus end of C909 to regulate the
output voltages.