Iiyama Vision Master Pro 451, Руководство по обслуживанию

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(4) Power management modes
When IC301 (main microprocessor) detects presence of horizontal and vertical sync signal and video signal,
control signal is output from IC104 (sub microprocessor). The control signal stops MAIN POWER circuit and
decrease heater voltage, and power consumption is reduced.
<Power save control signals>
Mode
Normal
Power
Management
Sync signal
H,V-Sync, VIDEO: ON
H,V-Sync,VIDEO: OFF
PS1
IC104 pin 8
HIGH
LOW
PS2
IC104 pin 15
LOW
HIGH
Circuit
All circuits are activated.
All circuits except for 5V line stop.
LED
IC104 pin 13
HIGH
(Green)
LOW
(Orange)
Q920 and K901 (RELAY) are turned off when "LOW" signal is output from 8 pin of IC104. AC input is not supplied
to PWB-MAIN when K901 is turned off as K901 switch AC input, and MAIN POWER circuit stops. Q921 is
turned off when "HIGH" signal is output from 15 pin of IC104. The output voltage of Heater output IC decrease
from 6.3V to 0V. The power consumption is 3W or less.
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4-2. SYNC SIGNAL PROCESSING circuit
The input sync signal from D-SUB connector is set input condition of VIDEO IN 1 / 2 and sync signal by IC105 (SW-
IC) and input to pins 2 (H / HV-IN), 5 (V-IN) and 3 (SOG) of IC101 (Sync-Processor). The input H/V-sync signal is
waveform-shaped and kept polality positive. HV (Comp.) and SOG signals are separated V sync signal. And the
input H/V sync signal is output from pins 13 (H-OUT) and 11 (V-OUT) and supplied to pins 41 (H-IN) and 42 (V-IN)
of IC301 (Microprocessor), and then output from pins 39 (H-OUT) and 40 (V-OUT) of IC301 and supplied to pins 26
(H-IN) and 27 (V-IN) of IC350 (H/V oscillation IC) to control the horizontal and vertical deflection.
The setting of signal input condition monitors H/V-sync signal applied to IC301, and output SIGNAL SELECT signal
from pin 9 of IC104 and S.O.G. switching signal from pin 7 of IC104.
(1) SIGNAL SELECT signal: Set VIDEO-IN 1/2 by controlling pin 13 of IC101.
D-SUB input
VIDEO-IN 1
VIDEO-IN 2
IC104 pin 9
LOW
HIGH
(2) The input sync signal to IC301 is processed by SYNC SIGNAL PROCESSING circuit in IC301 as follows:
Q
Discriminate the input sync signal type: Separate / Composite
R
Detect the input sync signal presence
S
Count the frequency
Counting criterion: X'TAL 12MHz (X301)