Sony RM-PJM50, Руководство пользователя

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4-10
VPL-FX50
source stops operations.
When “High” signal flows from the C board to CN1402
5
pin, it turns ON Q1405 and at the same time makes the
Photo coupler 1400 OFF. As the result, IC1400 pin
1
VSENSE becomes “High”, and QC board power source
starts operations.
For operating QC board, 3.3 V and 5 V are used. The
former is the straight output value after smoothing the
secondary side of the T1400, transformer, the later is the
one stepping-down the secondary output by the DC-DC
converter T1400 from 7 V to 5 V.
Meanwhile, 3.3 V and 5 V lines, MOS-FET Q1407 and
Q1408 for operating ON or OFF.
This operation aims at shortening a rising time of voltage
waveform supplied to the QC board.
When the DC-DC converter IC1405 rises up, its output is
input to IC1406 of the Delay-circuit to turn ON Q1408 and
next Q1407 in about 0.6 second.
With these MOS-FET Q1407/1408, about 20 to 40 ms can
be shortened.
4-4-2-3. Lens ..... Motor ..... Drive Circuit Operations
IC1605, IC1606 and IC1607 are drive ICs correspondingly
to drive ROCUS, ZOOM and SHIFT for the lens. These
controls are performed by the signal from the microproces-
sor in the C board only when CN 1600 pin (1) receives
“Low” signal.
When 3 bit signal is input to CN1600 pins (2) through (4),
operations are made by the gate circuit structured inside
like the PLD IC1603 for selecting FOCUS, ZOOM or
SHIFT or, to brake abnormal performances as an reversible
movements.
4-4-2-4. Details of Parts
.
R1416
This is a resistor to protect the power source of the
QC board. When a problem occurs in the later stage
of circuit, it opens the line to protect other parts.
.
IC1400
This is a control IC for the power source of the QC
board. It targets to control current resonance circuit.
.
T1400
Switching
.
Regulator
.
Transformer for current
resonance of the QC board power supply.
.
Q1401, Q1400
Q1401 and Q1400 are components to configure
switching-use MOS-FET and a half bridge circuit
for the QC board power supply.
.
C1408
This is a film capacitor for current resonance, which
forms a resonance circuit together with the T1400
coils( L component).
.
IC1405
IC1405 is a DC-DC converter to step-down the
secondary output about 7V of T1400 transformer to
5 V.
.
IC1402
A series regulator; steps-down from SUB 6 V to 5 V
for the FAN 5. It keeps operating when stand-by
state as well.
.
IC1406
This is comparator IC to delay the output voltage.