BenQ PB8220 - XGA DLP Projector, Service Manual

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Flyback Circuit
In a flyback converter operated in the discontinuous mode, the energy stored in
the flyback transformer must be zero at the beginning and end of each switching
period. During the on-time energy is stored in the transformer and energy taken from
the transformer when the switching transistor turn-off, the stored energy is all
delivered to the output.
Rectifiers Circuit
t reverse recovery time will be
minimized the loss.
Choosing the best rectifiers for any
switching power supply design is an
important process. The rectifiers are the
largest source if loss within switching
power supplies. To choose the best
rectifier, one must understand the
parameters that affect their efficiency. The
most important rectifier parameters are the
forward voltage (Vf) and the reverse
recovery time. The forward voltage drop creates a loss just by having voltage across the device
while high currents are flowing through it and the shortes
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