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6
﹒
Micro
(
IC301
)
6.1 H. sync / V. sync Processor
﹒
HS/VS
input
pin39
(
HS
)
﹐
pin40
(
VS
)﹐
IC301 individually to work on frequency
﹐
polarity
﹐
process of H+V
and
power
saving
﹐
then output horizontal sync
(
pin33
)
and vertical sync
(
pin32
)
of positive polarity to
IC401
STV9118
pin1
﹐
pin2
﹒
6.2
PWM
Control
The PWM control of IC301 is pin29
(
Brightness
)
and pin18
(
Rotation
)﹐
the PWM output via R
﹐
C after
rectified may control each function
﹒
6.3 Power saving / Mute / LED control
IC301 pin17
﹐
pin18 are power saving control pin
﹐
the condition of power saving and mode change
﹐
pin19 will
change from Low to Hi and active Mute function
﹒
Normal
Active
Mute L H
PD H L
(
Off mode
)
IC301
pin17
(
PD
)
function as LED control
﹐
the mode is as listed
:
Power On
Power saving
Over range freq
﹒
Pin17 Hi
Low
Low
6.4
CS
control
(
CS1 ~ HS2
)
To count H-SYNC by the output frequency
﹐
then output the cumulating as listed
:
Freq.
CS1 CS2 CS3 CS4 HS1 HS2
<
33K 0 0 0 0 0 0
33K~36K 0 0 1 1 0 0
36K~41K 1 0 0 0 0 0
41K~45K 1 0 1 1 0 0
45K~51K 0 1 0 0 0 0
51K~57K 0 1 0 1 0 0
57K~61K 0 1 1 1 0 1
61K~66K 1 1 0 0 0 1
66K~71K 1 1 0 0 0 1
71K~78K 1 1 1 0 1 1
78K~83K 1 1 1 0 1 1
83K~89K 1 1 1 1 1 1
>
89K 1 1 1 1 1 1
5
﹒
Tilt
IC301 pin18 PWM to tilt circuit
﹐
Q211 and Q213 control flow of current of Rotation coil
﹐
when the base of
C215 increase from 0 to 12V
﹐
As Q211 will turn on gradually
﹐
the current starts from 14V to 6.3V via Rotate
coil
﹒
When C215decrease from 12V to 0V
﹐
the current will change from 7V to GND
﹒
6.5
Key
Control
﹕
IC301 pin26~pin29 function as DAC switch input to control OSD display function
﹒
Pin40
:
﹒
Pin38
:▽﹒
Pin37
:△﹒
Pin39
:
﹒
6.6
I
2
C Bus
IC301 have two groups I
2
C bus to control E
2
PROM
﹐
IC401 deflection IC
﹐
Auto alignment
﹐
IC601 pre-AMP
﹒
1
2
22
ViewSonic
Corporation
Co
nfidential
-
Do
Not
Copy
G90f/B-3
Summary of Contents for G90f/B-3
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