ViewSonic VG910S Service Manual - Page 22

Circuit Description - power supply

Get ViewSonic VG910S - 19inch LCD Monitor PDF manuals and user guides
UPC - 766907009033
View all ViewSonic VG910S manuals
Add to My Manuals
Save this manual to your list of manuals

Page 22 highlights

4. Circuit Description 4.1 Power supply (DC/DC Converter): 4.1.1 IC251 MP1583 is a switching regulator controller that uses PWM method. That can be used for DC to DC conversion for step-down. It converts a 12V DC into regulated and stable output voltage of 5V. 4.1.2 Regulator: IC253 function is to convert a 5V into regulated and stable O/P 3.3V. D252, D253 are 3.3V convert 2.5V. 4.2 DDC data select: 4.2.1 IC601(AT24C02) saves D-SUB DDC data. 4.2.2 IC602(AT24C02) saves DVI, DDC data. 4.3 MCU The MTV312M micro-controller is an 8051 CPU core embedded device especially tailored for CRT/LCD Monitor application. It includes an 8051 CPU core, 1024-byte SRAM, 14 built-in PWM DACs, VESA DDC interface, 4-channel A/D converter, and a 64K-byte internal program Flash-ROM. The MCU controls the keyboard signal and audio signal. 4.4 Scalar The MST9131A is a high performance, and fully intergrated graphics processing IC solution for LCD monitors with resolutions up to SXGA. It is configured with an integrated triple-ADC/PLL, a high quality scaling engine, an on-screen display controller, a built-in output clock generator, an integrated DVI receiver, and LVDS display interface. To further reduce system costs, the MST9131A also integrates intelligent power management control capability for green-mode requirements and spread-spectrum support for EMI management. The analog input (CN602) signal and DVI-D input(CN601) signal are designed to be connected directly to scalar IC, The MST9131A built-in LVDS transmitter, is designed to be connected directly to panel. 4.5 Audio processor IC802(PT2313L) is a four-channel digital control audio processor utilizing CMOS Technology. Volume, Bass, Treble and Balance, Front/Rear Fader Processor are incorporated into a single chip. Loudness function and Selectable input gain are also provided to build a highly effective electronic Audio processor having the highest performance and reliability with the least external components. All functions are programmable using the I2C Bus. Volume signal through IC802 pin34(right) pin25(left) into audio amplifier. 4.6 Audio amplifier IC803(TDA1517) is an integrated class-B dual output amplifier, It contains two identical amplifier differential input stages. The gain of each amplifier is fixed at 20dB. Pins 1 and 9 are right and left channel inputs respectively. Pins 4 and 6 are right and left channel outputs which connect to two 4OHM speakers. Pin 8 is the mute/stand-by. ViewSonic Corporation Confidential - Do Not Copy VG910s/b 19

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
4.1
Power supply (DC/DC Converter):
4.1.1
IC251 MP1583 is a switching regulator controller that uses PWM method. That can be used for DC to
DC conversion for step-down. It converts a 12V DC into regulated and stable output voltage of 5V
.
4.1.2 Regulator:
IC253 function is
to
convert a 5V into regulated and stable O/P 3.3V.
D252, D253 are 3.3V convert 2.5V.
4.2
DDC data select:
4.2.1 IC601(AT24C02) save
s
D-SUB DDC data.
4.2.2 IC602(AT24C02) save
s
DVI, DDC data.
4.3
MCU
The MTV312M micro-controller is an 8051 CPU core embedded device especially tailored for CRT/LCD Monitor
application. It includes an 8051 CPU core, 1024-byte SRAM, 14 built-in PWM DACs, VESA DDC interface,
4-channel A/D converter, and a 64K-byte internal program Flash-ROM.
The MCU control
s
the keyboard signal and audio signal.
4.4
Scalar
The MST9131A is a high performance, and fully intergrated graphics processing IC solution for LCD monitors
with resolutions up to SXGA. It is configured with an integrated triple-ADC/PLL, a high quality scaling engine,
an on-screen display controller, a built-in output clock generator, an integrated DVI receiver, and LVDS display
interface. To further reduce system costs, the MST9131A also integrates intelligent power management control
capability for green-mode requirements and spread-spectrum support for EMI management.
The analog input (CN602) signal and DVI-D input(CN601) signal are designed to be connected directly to scalar
IC, The MST9131A built-in LVDS transmitter, is designed to be connected directly to panel.
4.5
Audio processor
IC802(PT2313L) is a four-channel digital control audio processor utilizing CMOS Technology. Volume, Bass,
Treble and Balance, Front/Rear Fader Processor are incorporated into a single chip. Loudness function and
Selectable input gain are also provided to build a highly effective electronic Audio processor having the highest
performance and reliability with the
l
east external components. All functions are programmable using the I
2
C
Bus.
Volume signal through IC802 pin34(right) pin25(left) into audio amplifier.
4.6
Audio amplifier
IC803(TDA1517) is an integrated class-B dual output amplifier, It contains two identical amplifier differential
input stages. The gain of each amplifier is fixed at 20dB.
Pins 1 and 9 are right and left channel inputs respectively. Pins 4 and 6 are right and left channel outputs which
connect to two 4OHM speakers.
Pin 8 is the mute/stand-by.
4. Circuit Description
19
ViewSonic Corporation
Co
nfidential
- Do Not Copy
VG910s/b