Sony RM-PJM50, Руководство пользователя

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4-4
VPL-FX50
RY1000 turns ON in the state of set
.
stand-by and
shorts-circuit both ends of R1000.
4-4-1-2. Active Filter
(1) ON/OFF Operations
At stand-by the active filter does not operate due to
IC1000 pin
8
keeps “Low” by the Q1001. The active
filter starts operations by receiving “High” signal from
the microprocessor in the Y board and subsequently
the CN1207 pin
1
turns “High” when Q1001 goes
OFF, Q1004 turns ON and further Q1005 also turns
ON.
As a result, VCC is supplied to IC1000 pin
1
result-
ing in start of the active filter.
(2) Basic operations
In conventional rectification circuits that do not use the
active filter, peak recharge current is generated in a
part of the AC voltage waveform due to the capacity
components of the smoothing capacitor.
This may cause to invite problems of large power
consumption against the effective power, and Higher
harmonic, etc., and may cause subsequent problems
for other equipments, too.
In order to prevent these, the power supply circuit is
equipped with a step-up DC-DC converter in the
smoothing circuit and adopts an active filter that
proportionates the input current waveform to the input
voltage waveform by appropriate control.
The operations by this active filter circuits is thus
performed critical just as those series of VPL-X30 and
VPL-VW10HT, but different from the case of VPL-
X600 and VPL-SC50 each series.
Fig.2 shows the principle of the active filter circuit.
When FET Q1008 turns ON, energy is accumulated in
the chalk coil L1002.
When it turns OFF, energy is discharged, and current
flows to the load side.
Fig.3 shows the relation between the voltage and
current. The average input current for each switching
cycle of the FET Q1008 is the half of value of the peak
current that flows to the chalk coil L1002. Since these
peak values can be placed on the curve proportionate
to half the AC voltage (Sign curve) input, they appear
like resistance load on the AC voltage from the input
side of the active filter.
Sense resistor R1037 detects the current flowing into
4-4-1. GA Board
4-4-1-1. Structure
(1) EMI Filter
Fuse F1000 (6.3A/250V, conformed to the Safety
Standard ) is available for use anywhere regardless of
marketing zone of 100V, or 200V.
This F1000 is the same fuse used in the series of
VPLX600, VPL-SC50 and VPL-PX30.
(2) Active Filter
The active filter improves the power factor of the AC
voltage after bridge rectification, and at the same time,
serves as a step-up converter and supplies DC 345
±
10V to each for the lamp in the later stage, power
supply source for circuits, and for the GB board(Power
source for the QC board).
However, when the maximum AC voltage exceeds the
output voltage of the active filter, the power factor will
not be improved correctly.
(3) Circuit Power Source
It is DC-DC converter operations efficiently performed
from Stand-by, Power ON and till lamp cooling by
current resonance, optimizing controls of oscillating
frequency.
With the operations of the circuits power source at the
time of “Stand-by”, AC voltage is fully rectified to DC
voltage and stepped-down to the SUB6V for the
microprocessor and to the VCC for the Control IC for
circuit power sources, including the active filter
Control IC.
.
VCC (19
±
1.0 V)
.
SUB6V (6.3
±
0.2 V)
.
17V (16.8
±
0.8 V)
.
6.3V ( 6.3
±
0.2 V)
. _
6V (
_
6.4
±
0.3 V)
.
4.8V (4.8
±
0.3 V)
.
12V (11.5
±
0.8V)
.
FAN + B1, 2, 3, 4 (variable output)
(4) Inrush Current Limit Circuit
When the AC voltage is supplied with the electric load
of the smoothing capacitors C1013 and C1016 fully
discharged, the inrush current flows to the capacitor.
As a result, it damages the fuse F1000 in the input
stage. To prevent this, immediately after inputting the
AC voltage, the inrush current is restricted by the
R1000.
After the circuit power sources is initialized, Relay