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4.4 INTRODUCTION OF IC
STUM16AK(U401):
integrate ADC, OSD, SCALER, MCU, LVDS, convert analog RGB
into digital and room and shrink scaling output to LCD panel.
PIN Function:
AIC1084-33PM (U702):
DC power convert, used to 5v convert 3.3v.
LT1117-18(U701):
DC power convert, used to 5v convert 3.3v.
TPA3003D2 (U601):
The TPA3003D2 is a audio amplifier IC,3-W efficient, driving
speakers as low as 8
, range of gain from -40dB to 36 dB. The function of
each pin and the inside circuit diagram are as follows
:
Pin Symbol
Description
70
SDO
SPI flash serial data output; Input w/5V-tolerant
71
CSZ
SPI flash chip select; output
72
SCK
SPI flash serial select; output
73
SDI
SPI flash serial data input; output
65
DDCA_SDA/RS232_TX
DDC data for analog interface; 4mA driving
strength/UART transmitter/GPIO; I/O w/5V-tolrant
66 DDCA_SDA/RS232_RX DDC data for analog interface/UART
transmitter/GPIO;Input w/5V-tolrant
19
RST
Chip reset; High reset; Input w/5V-tolerant
22
RSTN
Chip reset; Low reset; Input w/5W-toerant
11 VCTRL
Regulator
control;
Output
63 HSYNCO
Analog
HSYNC
input
64 VSYNCO
Analog
VSYNC
input
62
REFP
Internal ADC top de-coupling pin
61
REFM
Internal ADC bottom de-coupling pin
51 REXT
External resistor 390 ohm to AVDD
_
ADC
21
PWM1
PWM1; 4mA driving strength; Output
29
PWM0
PWM0; 4mA driving strength; Output
4 BYPASS
For
External
Bypass
Capacitor
32
XIN
Xin; Crystal Oscillator Input
33
XOUT
Xout; Crystal Oscillator Output
44
、
50
、
60 AVDD
_
ADC
ADC Power 3.3V
52
AVDD
_
PLL
PLL Power 3.3V
34
AVDD
_
MPLL
MPLL Power 3.3V
14
、
67
、
95
、
103
、
115
VDDP
Digital Output Power 3.3V
12
、
68
、
97
、
117
VDDC
Digital Core Power 1.8V
ViewSonic Corporation
VA503b-1_ VA503m-1
21
Confidential - Do Not Copy
Summary of Contents for VA503b-1
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Page 78: ...ViewSonic Corporation Confidential Do Not Copy VA503b 1_ VA503m 1 75 11 PCB Layout Diagram...
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Page 81: ...ViewSonic Corporation Confidential Do Not Copy VA503b 1_ VA503m 1 78 POWER PCB VIEW...
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