Acer AL2002 AL2002 Service Guide - Page 9

8 3.5. Interface Boards (Digital TMDS Input) Go to cover page 3.5.1. The interface board will house the Panel-Link receiver , and transmitting TTL level signals into LCD Module to driver the LCD display circuit. 3.5.2. Video Signal Amplitudes This video inputs consist of TX 0 ±, TX 1 ±, TX 2 ± and CLK ± signals, each with its own shielded twisted pair. These video signals are digital levels, when each signal pair is terminated by a normal 100 ohms .The panel-Link signal transmitting over the cable is based on 3V DC offset with ± 0.5V amplitude. 3.5.3. Video Signal Termination Impedance This panel link signal termination shall be 100Ω per pair which shall be resistive with a negligible reactive component. 3.5.4. Signal Connector (DVI-D 24 pin) This signal cable connector shall be white color, molded - over and shielded twisted pair cable with 50Ω impedance per line or 100Ω ±10% per differential pair. The cable shall be 2000 mini-meters long. 3.6. User Controls and Indicators: 3.6.1. Power On / Off Switch The monitor shall have a power control switch visible and accessible on the front of the monitor. The switch shall have no effect on the operation of the AC / DC converter. Instead, it shall interrupt the DC supply to the monitor. 3.6.2. Power Indicator LED The monitor shall make use of a LED type indicator located on the front of the monitor. The LED color shall indicate the power states as given in Table below. LED Color Power-ON Mode : Green Power Saving Mode : Amber 3.6.3. On-Screen Display The On Screen Display system shall be used, controlled by a select button (SELECT), a menu button (MENU), a plus (+) button and a minus (-) button. If the buttons remain untouched for OSD turn off time while displaying a menu, the firmware shall save the current adjustments and exit. Also, if the video controller changes video mode while the OSD is active, the current settings shall be saved immediately, the OSD turned off, and the new mode is displayed. A. Menu Operation Pressing the MENU button the first time brings up the first menu level. The (MENU) button is used to enter and exit the OSD menu. Pressing the MENU button brings up the second menu level for the item selected.