NCR 7454, User Manual, Page: 42 / 244

1-22 Chapter 1: Product Overview
LCD Backlight Inverter Module
An Inverter Board supplies power for the LCD Backlight, which is a
separate module in the terminal. The inverter has a connector that
receives power, ground, and a Backlight dimming signal from the
Processor Board. The inverter generates the high voltage necessary to
start and run dual CCFL Backlights.
A fuse located on the Inverter Board protects power to the inverter.
This fuse protects the system from damage in the event of a Backlight
or Inverter Board fault. The fuse is not field replaceable; if it blows, the
safety characteristics of one or more components on the Inverter Board
may have been compromised and the Inverter Board should be
replaced.
If one or both Backlight tubes become disconnected or otherwise open-
circuited, protection circuitry shuts down the inverter. This avoids
over-powering a single tube and also protects against high voltage
shorting.
Touch Screen
The Touch Screen completely covers the LCD and is mounted directly
in front of the LCD, behind the front plastic bezel of the terminal. The
touch controller on the Processor Board supports capacitive and
resistive touch glass.
The touch glass has an integrated harness that is routed into the
Processor Board enclosure and is connected to a header on the
Processor Board. The touch glass has a glare-reducing texture that also
helps hide fingerprints.