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ViewSonic Corporation
Confidential - Do Not Copy
VA702-1_VA702b-1
23
4 NC
9 +5V(from
PC)
14 VSYNC
5
Cable Detect
10
GND
15
Data clock line (SCL)
7. Key Parts Pin Assignment
7.1
IC802 (TOP246Y, Power Control IC)
Pin
Symbol
I/O
Description
1 C I
Control
2 L I
Line
Sense
3 X I
External
Current
Limit
4
S
O
Source of MOSFET(GND)
5 F I
Frequency
6
D
I
Drain of MOSFET
7.2
IC501 (OZ9910G, CCFL inverter controller IC)
Pin No.
Symbol
I/O
Description
1 NDRV4 O
Bottom MOSFET gate drive output in dual forward
converter
2 PGND
High-current
power
ground
3 NDRV2 O
Bottom MOSFET gate drive output in dual forward
converter
4 GNDA
Low-current
signal
ground
5
CT
I
Timing capacitor of high frequency oscillator
6
LCT
I
Timing capacitor of set LPWM frequency
7
ADJ
I
Control command input –DC
8 ENA I
Enable
input
9 VSEN I
Voltage sense feedback
10 CMP_SST I
Soft start and loop compensation capacitor
11 ISEN I
Current sense feedback
12 VREF O
Reference voltage output
13 VIN I
Supply voltage for IC
14 HSB I
High side driver buffer output
15 PDRV3 O
Top MOSFET gate drive output in dual forward converter
16 PDRV1 O
Top MOSFET gate drive output in dual forward converter
7.3
U104 (TSU16AK)
Pin
Symbol
I/O
Description
1 LVBOM
O
B-Link Negative LVDS Differential Data
2 GND
Ground
3 BYPASS
For External Bypass Capacitor
4 NC
Not
connected
5 NC
Not
connected
6
BUSTYPE
IN
Low : Serial bus; High : Direct bus
7 NC
Not
connected
8 NC
Not
connected
9 NC
Not
connected
10 GND
Ground
11 VDDP
O
Digital Output Power
12 NC
Not
connected
13 NC
Not
connected
14 NC
Not
connected
15 NC
Not
connected
16 NC
Not
connected