Read Sharp AL-1566 (serv.man15) Service Manual online
AL-1556/1566 ELECTRICAL SECTION 12 - 13
When Q001 turns off, energy accumulated in the transformer (T001)
flows a current of waveform C in the path indicated with dotted line as
shown in the figure above through D101 and D113 and dissipates to
the secondary output side. When this energy is exhausted, the current
flowing through D101 and D113 turns off. However, the N
flows a current of waveform C in the path indicated with dotted line as
shown in the figure above through D101 and D113 and dissipates to
the secondary output side. When this energy is exhausted, the current
flowing through D101 and D113 turns off. However, the N
S
winding has
a slight remaining energy, which generates a voltage in the base wind-
ing N
ing N
C
and turns on Q001 again to repeat switching operation, supply-
ing a high frequency power to the secondary side.
(4) Overcurrent protection circuit (Primary side)
The ON period extension due to an increased output load is detected,
and the OFF period of Q001 is extended by the control circuit, and
energy accumulated in the primary winding of the transformer T001 is
reduced, providing protection against an overcurrent. Refer to Fig. (4).
and the OFF period of Q001 is extended by the control circuit, and
energy accumulated in the primary winding of the transformer T001 is
reduced, providing protection against an overcurrent. Refer to Fig. (4).
(5) Rectifying/smoothing circuit (+5V)
fig (6) Rectifying/smoothing circuit
The high frequency pulse generated by the inverter circuit is
decreased by the converter transformer, rectified by the high frequency
diode D113, and smoothed by C107 and C108.
decreased by the converter transformer, rectified by the high frequency
diode D113, and smoothed by C107 and C108.
fig (7) +5V rectifying/smoothing circuit voltage waveform
Voltage waveform
Voltage waveform
Click on the first or last page to see other AL-1566 (serv.man15) service manuals if exist.