Acer AL708 Schematic

Front Side

Rear Side

L7EA (AL708) 1-1

2. GENERAL INFORMATION

1. OUTLINE 2.8 Superior display performance

This monitor is 17" multi-scan color LCD display High contrast : 350 : 1

with the following features. High brightness : 250 cd / m

OSD ( on screen display ) control allows easy user Wide view angle : 140 / 100 degrees (H/V)

adjustment.

Power saving function, which helps saving energy , 2.9 Special function

is also one of the highlights of this model. VESA DDC2B ( Display Data Channel )

Compatible

2. FEATURES

2.1 Power Saving

Built in Power Saving function based on VESA-

DMPS standard. Power energy shall be saved

by controlling the circuit in accordance with

power saving signal from computer.

2.2 OSD (on screen display) function

OSD ( 5 Languages ) function is excellent and

new man-machine interface.

Anyone is able to set up the picture as he like

through OSD menu.

2.3 Self Test function

Self Testing picture comes out by pushing special

key in the case of no-connection with computer

or power saving operation.

This function shows if monitor is alive or not and

can be used for self aging test.

2.4 Ergonomic design

Low emission design to meet MPR II and TCO

2.5 Multi scan with digital technology

8 bit micro controller controls the circuit

operation to meet with wide range signal of Fh=

30~81 kHz and Fv= 56~75 Hz. So VGA640x400,

VGA640x480, SVGA800x600, XGA 1024x768,

SXGA 1280x1024 mode are applicable.

2.6 Factory preset

The product has 26 memory mode in total .

17 modes are preset and 9 modes are user

definable.

2.7 Fine dot pitch

LCD panel with a fine dot pitch

( Horizontal : 0.264 mm / Vertical : 0.264 mm)

2

(Typical)

L7EA (AL708) 2

3. SPECIFICATION

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1. Outline 4.2 Audio : Line-in receptacle

1.1 POWER SW, LED,UP.DN,LEFT,RIGHT,SEL

and MENU key are located on the front panel.

1.2 Video signal connector, audio line-in receptacle

and DC-IN are located on the back side of

the cabinet.

1.3 OSD menu includes the following function.

CONTRAST BRIGHTNESS H.POSITION

V.POSITION COLOR-TEMPERATURE 4.3 Video signal connector 15P Mini D-Sub

CLOCK PHASE LANGUAGE

VOLUME POWER-ON-RECALL

1.4 CONTRAST and BRIGHTNESS can be

directly controlled with UP / DN key.

1.5 VOLUME can be controlled with LEFT /

RIGHT key.

2. MECHANICAL SPECIFICATIONS

2.1 Dimension Height : 418 mm ( 16.5")

Width : 408 mm ( 16")

Depth : 183 mm ( 7.2")

2.2 Net Weight :5.6 kg ( 12.4 lbs)

2.3 Maximum Viewable Area : Diagonal 432 mm

(17")

3. PANEL SPECIFICATIONS

connector x 1

PI

1 RV Red Video

J1

1

2
3

PHONEJACK STEREO

CN6

162738495

16 17

11

12

13

14

10

DB15HD

15

MNEMON SIGNA

Part No. AA0170E1003

Driver bit of panel 8 bit

Contrast ratio 350:1 t

Brightness 250 cd/ m2

Pixel pitch 0.264 mm

Response time < 30 ms (Tr+Tf

View angle 75/75/65/60

Color coordinate x=0.313,y=0.329

4. CONNECTORS

4.1 AC inlet : CEE22 typed connector

2 GV Green Video

3 BV Blue Video

4

one

5 GND Ground(DDC return

6 RG Red GND

7 GG Green GND

8 BG Blue GND

9 +5V + 5V (for DDC

10 SG Sync GND

11

one

12 SDA DDC Data

13 HS Horizontal Sync

14 VS Vertical Syn

15 SCL DDC Cloc

5. ELECTRICAL SPECIFICATIONS 5.4 Preset Timings

5.1 Standard conditions

Display area 338 x 270 mm

Video signal level 0.7 Vpp

Contrast Max.

Brightness Max.

Ambient 20 +/- 5 C degrees

Input voltage AC 120,60Hz

Warming up time > 30 minutes

Display mode 1280 x 1024

5.2 POWER

5.2.1 Power supply

Input voltage 90~240 Volts

Power frequency 50 / 60 Hz, +/-3

Input current < 0.5 A

Inrush current < 1 A

Power < 50 Watts

# mode Resolution Hz (KHz)

1 IBM VGA 720 x 400 70 31.46

2 VESA 640 x 480 60 31.46

”

4 VESA 640 x 480 72 37.86

6 VESA 800 x 600 56 35.16

7 VESA 800 x 600 60 37.87

8 VESA 800 x 600 72 48.07

9 VESA 800 x 600 75 46.87

1

MAC 16” 832 x 624 75 49.72

1

VESA 1024 x 768 60 48.36

1

VESA 1024 x 768 70 56.48

1

VESA 1024 x 768 75 60.02

1

VESA 1152 x 864 75 67.5

1

VESA 1280 x 1024 60 63.98

5.2.2 Power Management

1

VESA 1280 x 1024 75 79.97

State Power Indicator

On < 50Watts Green

Standby < 5 Watts Amber

Off < 5 Watts

5.3 Acceptable timing using 0,7 Vp-p Video signal.

If your timing is within following specification, 5.5.2 Sync Signal level

this LCD display can automatically function with H/V Separate : TTL level

a certain position. 5.5.3 Input impedance

Horizontal: Sync frequency : 30~81 kHz Video input : 75 ohms

Vertical : Sync frequency : 56~75Hz Sync input : > 1 k ohms

5.5 Signal level and input impedance

5.5.1 Video Signal level

This LCD display is adjusted at the factory

5.6 Display Area 6. ENVIRONMENTS

Display area : 338 x 270 mm

Operation Storage and

0 ~ 40 C -20 ~ +60 C

5.7 General performance

5.7.1 Maximum pixel clock

135 MHz

5.7.2 Maximum luminance

Tempera

Humidit 5 ~ 90 %

5 ~ 90 % *

Value 250 cd / m2 at center of the

Altitude 3000m 12000m

display area ,Specified by
6500K + 8 MPCD

Conditions Display image : Full white

Brightness : Maximum
Contrast : Maximum

5.7.3 Brightness variation 7.2 EMC standards

Value 75 % Variation = C / A x 100

Conditions Display image: Full white

Brightness : Maximum
Contrast : Maximum

* Non-condensation

7. REGULATORY STANDARDS

7.1 Safety standards

This monitor applies to various safty & EMI

standards May refer to the logo label

FCC part 15,subpart B , class-B

CE marking

8. OTHERS

TUV (Rheinland)

ISO13406-II pixel fault class 2

TCO99

A: Luminance at center
position
C: Luminance at position of
lowest brightness

5.7.4 Contrast ratio (CR)

Value CR= B / A

Conditions Contrast : Maximum

B: Full white pattern
Brightness : min
A: Full black pattern
Brightness : max

9. P0WER CORD

Northern Hemisphere Version : UL / CSA

approved power cord.

European : VDE approved power cord.

10. SIGNAL CABLE

Signal cable with Mini D-Sub 15P connectors at

both ends.

Length : 1.5 meter.

11. RELIABILITY

11.1 MTBF for completed unit without LCD

> 30,000 hours (demonstrated MTBF)

11.2 MTBF for LCD

The brightness is still more than 50% of the

original brightness after 25,000 hours (min.)

4. THEORY OF OPERATION

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This section describes the function of the LCD monitor per functional block.
L7EA monitor includes MB board, audio board (option), inverter board, adapter and button board.

4.1 MB BOARD

The MB board is a four-layer, single-landed design with ground and internal planes provided. DC power
from the power adapter enter the board through DC jack. Other connectors on the board are for inverter,
audio and button board .The VGA cable is a signal cable that contains video signal, sync signal and DDC
signal from PC VGA adapter.
This system board consists of 4 functional areas : flat panel controller, flash ROM , power regulator and

LVDS transmitter.

4.1.1 Flat panel controller…… gm2120 (U8)

The heart of the system board is Genesis gm2120. The gm2120 is a graphics processing IC for LCD

monitor. It provides all key IC functions required for LCD panel. On-chip functions include a
high-speed triple-ADC , PLL, high sacling engine, OSD controller and on-chip microcontroller.

a) Clock Generation :

Crystal Input Clock (TCLK and XTAL). This is the input pair to an internal crystal oscillator and

corresponding logic. A 14.318 MHz crystal is recommended.

b) Hardware Reset ( Pin 5 )

Hardware Reset signal is generated by MAX6326 (U10).It assert a reset signal at least 100 ms.

c) Analog to Digital Converter

The gm2120 chip has three ADC's (analog-to-digital converters), one for each color (red, green and blue)
The analog RGB signals are connected to gm2120 as described below

Pin Name Pin Numbe

Red + 171

Red - 170

Green + 167

Green - 166

Blue + 163

Blue - 162

d) OSD :

The gm2120 has a fully programmable ,high-quality OSD controller.The on-chip static RAM(4096 words
by 24 bits) stores the cell map and the cell definitions.

e) On-Chip Microcontroller (OCM)

The gm2120 on-chip microcontroller(OCM) serves as the system microcontroller.That is , it programs the
gm2120 and manages other devices in the system such as the keypad, the backlight, LED, audio and
non-volatile RAM.using general purpose input/output (GPIO) pins.

2

Pin Number Pin Name Pin Usage

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40 GPIO0 / PWM0 Backlight contro

41 GPIO1 / PWM1 Volume control

42 GPIO2 / PWM2 Key-Lef

43 GPIO3 / TIME

44 GPIO4 / UART_DI Debug Purpose

45 GPIO5 / UART_DO Debug Purpose

46 GPIO6 Key-Righ

47 GPIO7 Key-Dow

39 GPIO8 / IRQIN

48 GPIO9 Key-Se

49 GPIO10 Key-Men

50 GPIO11

51 GPIO12

52 GPIO13

205 GPIO16 / HFS

1 GPIO17

208 GPIO18

207 GPIO19 Key-Power, on / off contro

Key-U

LED-Oran

o use

V- RAM (U4) SD

V- RAM (U4) SC

V- RAM (U11) SC

o use

o use

206 GPIO20 Mute , audio disable

4 GPIO21 / IR

204 GPIO22 / HCL

f) Panel Power Sequencing ( PPWR, PBIAS) ( Pin 113~114)

0 has two dedicated outputs PPWR and PBIAS ( Pin113 and Pin114) to control LCD power

sequencing once data and control signals are stable.

g) Parallel ROM Interface Port (Pin 8~25, Pin28~35)

The gm2120 has parallel ROM interface port , pin8~25 for address bus, pin28~35 for data bus.

h) Panel interface (Pin 55~66, Pin69~80, Pin83~87, Pin90~96.Pin99~110)

The gm2120 driver interface is highly programmable. It supports dual bus / dual port for SXGA drivers.

4.1.2 LVDS Transmitter DS90C383 (U1,U2)

The DS90C383 transmitter converts 28 bits of TTL data into four LVDS ( Low Voltage Differential

Signaling) data streams. A phase-locked transmit clock is transmitted in parallel with the data streams
over a fifth LVDS link. At a transmit clock frequency of 85 MHz, 24 bits of RGB data and 3 bits of LCD
timing and control data ( FPLINE, FPFRAME, DRDY) are transmitted at rate of 595 Mbps per LVDS
data channel. U1 AS the ODD pixel transmitter , U2 as the EVEN pixel transmitter.

LED-Gree

V- RAM (U11) SD

4.1.3 Power Regulator AIC1563 (U12),LT1117 (U5, U6)

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The AIC1563 is a monolithic control IC containing the primary functions required for DC to DC converters.
The device consists of an internal temperature compensated reference, conparator, controlled duty cycle

oscillator with an active current sense circuit. Desired output voltage are determined by the equation

Vout = 1.25 ( 1 + R104 / R103), In this case, the output voltage are 5 Volts.
The AIC1117 is a low dropout positive adjustable regulator with minumum of 1A output current capability.
So it is well suited for 3.3 V and 2.5 V Rregulator.

U6 as a 2.5 V regulator , Desired output voltage are determined by the equation
Vout=5 x ( R53 / R53+R56)= 2.5
U5 as a 3.3 V regulator , Desired output voltage are determined by the equation
Vout=5 x ( R30 / R30+R36)= 3.3

4.2 Audio Board AN7522 (U1)

The AN7522 is a 2 channel audio power amplifier capable of delivering 2W of continuous average power

to an 8 ohms with less than 0.5% (THD) from a 12 V power supply.

An7522 can directly drive 8 ohms speaker , does not require output coupling capacitor, bootstrap capacitor
,or snubber network. Audio line-in are feed into pin 6,8 of the AN7522. The output power is controlled by
the DC voltage of pin 8 from gm2120 GPIO port.

4.3 Inverter Board

This is a specific inverter for L7E monitor backlight which converters 12 Vdc to drive four cold cathod
fluorescence tubes. Electrical specification describled as below.

INPUT

OUTPUT

Rated Input Volta

Maximum Input Voltage 11.4~12.6 Vdc

Input Curren

Off state Input Powe

On / Off Voltage 2~3.3 for On, 0~1 for Off

Rated Output Strike-on Voltage 1310 Vrms

Rated Output Voltage 710 Vrms at 6 mA

Rated Output Frequenc

Rate Output Current per tube 6 mA

12Vdc

< 2A

< 0.1 W

45~60KHz

4.4 Adapter

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This is a general purpose AC / DC adapter which converter 90~240 Vac to a stabilized DC voltage 12 V
with rated output current of 4.16A . Electrical specification describled as below.

INPUT

OUTPUT

Rated Input Voltage 90~240 Vac , 50/60 Hz

Operation Input Volta

Input Curren

Inrush Current (Cold Start

Standby Input Powe

Rated Output Voltage 12 Vdc

Output Voltage Regulatio

Output Ripple and Noise < 600 mVp-

Rate Output Curren

Turn-on Dela

90~260 Vac, 47~63 Hz

< 1.5A

< 100A @ 120Vac

< 1.5 W at 120Vac

+ 10 / -5 %

< 4.16A

< 1 Secon

5. DISASSEMBLY INSTRUCTIONS

1. Stand& rear cover removal

1) remove four large screw "1" from
the rear cover

2) remove the rear cover

3) remove four screw "2"

4) remove the stand

2

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2. ESD cover removal

1) remove four screw "3"

2) remove the ESD cover

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3. MB board removal

1) remove four screw "4"

2) remove the MB board

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