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1.1.7
Degaussing circuit
(1) The automatic and manual degaussing circuit is provided.
The circuit prevents the picture from dropping its quality due to the magnetization on CRT,
and operates as follows.
(2) When powering ON, Q963 flows to activate RY901 by DG signal output by the MPU.
This will make the current flow through the demagnetizing coil for demagnetization. The
demagnetizing time is approximately 5 seconds.
Manual demagnetization becomes possible by selecting the demagnetizing menu on the
OSD picture.
1.1.8
Power management circuit
Turn ON the power management setting on the menu picture of OSD, and the energy saving
mode shown in Table 2 will be ready depending on whether the horizontal/vertical sync. signal
is present or not.
1.1.9
Protective circuit
(1) Overcurrent protective circuit (primary side)
IC902 is provided with an overcurrent protective circuit. The voltage drop generated by the
drain current that flows into R928 is input to Pin 1 (OCP/FB terminal) of IC902. When the
voltage reaches 0.73V, the overcurrent protective circuit will be activated.
(2) Overcurrent protective circuit (secondary side)
To protect the parts on the secondary side, the short-circuit detection circuit is provided on
the secondary side output (+215V, +80V, +/-15V, +7.5V), one for each. As an example of
+215V, the output line of +215V is monitored with R964, R965, D966 and Q961. If it drops
beyond approx. +140V for any reason, Q961 will be turned ON to transmit the information
to the MPU. Then, since the MPU sets P-SUS signal at LOW, Q902 will be turned OFF to
cut off the power to IC902 in order to stop IC902. (IC901 will be also stopped at the same
time.) The overcurrent protective circuit is designed to be activated when the output volt-
age drops approx. 30 to 40%.
(3) Overvoltage protective circuit
R918, R919, R920 and R921 are used to detect the overvoltage in the higher harmonic
circuit, and the tertiary coil (Pin 9) of T901 is used to detect the overvoltage of the voltage
on the secondary side. They are both connected to the overvoltage protective circuit
(Q904, Q905) on the primary side. If any overvoltage results for any reason, Q905 will be
turned ON to turn ON Q904. Then Q902 will be stopped. Since the power for IC901 and
IC902 is cut off as Q902 is stopped, the switching operation will be stopped.
OFF
ON
On
Off
On
Off
On
On
Off
Off
Active
Blank
Blank
Blank
Power Save
Video
H-sync
V-sync
LED indicator
140W
3W
Power
consumption
Recovery
time
¥
5 sec.
Green
Orange
Summary of Contents for MultiSync FP1355 FP1355 FP1355
Page 23: ...1 17 Q502 Q502 Damper diode Current waveform fh 106k ...
Page 25: ...1 19 Q502 Q502 Damper diode Current waveform Q502 Ic Q502 Vce ...
Page 58: ...1 52 Figure 25 IC211 MC13289ASP block diagram ...
Page 63: ...1 57 Figure 30 IC212 XC3824P2 block diagram ...
Page 65: ...1 59 1 11 Wave form of main circuit voltage ...
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Page 120: ...MultiSync FP1355 User s Manual ...
Page 144: ... VSP C0464 REVISE 2 ...
Page 166: ...Fig 2 BEZEL LOGO VSP C0464 COLOR OF LETTERING Kingfisher Blue 6704 11 5 24 5 66 ...
Page 169: ...VSP C0464 Fig 5 1 PRINTING SPECIFICATION OF CARTON BOX North America ...
Page 170: ...VSP C0464 Fig 5 2 PRINTING SPECIFICATION OF CARTON BOX Europe ...
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