NEC DPro2070SB, Service Manual

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1.3.4 2 Input change circuit
The analog switch IC216 carries out the signal selection at the time of SIGNAL-A and B simultaneous
input. The signal selection is carried out by the SELECT signal of pin 3 of microcomputer IC102. By the
SELECT signal of pin 3, the input signal of SIGNAL-A is selected when pin 13 (SELECT SW) of the
analog switch IC206 is HIGH, and SIGNAL-B is selected when pin 13 (SELECT SW) of the analog switch
IC206 is LOW.
1.3.5 Sync on Green circuit
The Sync on Green signal input needs to make an image signal and a composite sync signal separate.
The separation method of the image signal and the composite sync signal is as follows. If a
microcomputer IC102 detects a Sync on Green signal, pin 18 S/G-SEL signals of IC211 will be set to
HIGH (5V), a transistor Q280 turns off, and the Sync on Green signal is output from pin 23 of IC216. The
Sync on Green signal output from pin 23 is input to pin 22 of IC216, it is divided to the image signal and
the composite sync signal at the inside of IC216, and only composite sync signal is output from pin 21.
1.3.6 Asset circuit
If the monitor power is turned OFF, 5V power will be supplied to pin 14 of EEPROM (IC217) from the PC
via pin 9 of CN216, and the data stored in the EEPROM (IC217) can be read out from I2C bus.
1.3.7 AUTO-SIZE function
The AUTO-SIZE function detects the phase data of RGB OR signal (output to pin 11 of OSM (IC212) from
pin 15 of AMP (IC211) from H-OSM and V-S signals input to pins 5 and 16 of IC212 in order to
automatically adjust the screen to the optimum width and position.
Using the OSM, select AUTO SIZE ADJUST, and then press (+) button to perform automatic size
adjustment.
1.3.8 SB MODE (Super Bright Mode) function
1.3.8.1 Adjustment item/operating function in selecting SB Mode
→
SUPER BRIGHT MODE OFF (in factory adjustment state)
↓
SUPER BRIGHT MODE-1 ON (PICTURE)
↓
SUPER BRIGHT MODE-2 ON (MOVIE)
↓
User adjustment items related to luminance/color coordination
Adjustment of
brightness
Adjustment of
contrast
Color mode
selection
Color
temperature
selection
Individual GAIN
adjustment
SUPER BRIGHT MODE
OFF
Adjustable (*1) Adjustable (*1) Selectable Selectable (*2) Adjustable (*4)
SUPER BRIGHT MODE-1
ON
Adjustable (*1) Adjustable (*1) Not-selectable Selectable (*2) Not-adjustable
SUPER BRIGHT MODE-2
ON
Adjustable (*1) Adjustable (*1) Not-selectable Selectable (*2) Not-adjustable
(*1): Brightness and contrast are common among three display mode.
(*2): For color temperature, the adjustment value is memorized in every display mode.
(*4): See (*4) mentioned in item 1.3.8.3.