Teledyne API T803 CO2/O2 Analyzer Operation Manual Principles of Operation
221

12.6.8. FRONT PANEL TOUCHSCREEN/DISPLAY INTERFACE

Users can input data and receive information directly through the front panel
touchscreen display. The LCD display is controlled directly by the CPU board.
The touchscreen is interfaced to the CPU by means of a touchscreen controller
that connects to the CPU via the internal USB bus and emulates a computer
mouse.
Figure 12-13: Front Panel and Display Interface Block Diagram
12.6.8.1. LVDS TRANSMITTER BOARD
The LVDS (low voltage differential signaling) transmitter board converts the
parallel display bus to a serialized, low voltage, differential signal bus in order to
transmit the video signal to the LCD interface PCA.
12.6.8.2. FRONT PANEL TOUCHSCREEN/DISPLAY INTERFACE PCA
The front panel touchscreen/display interface PCA controls the various functions
of the display and touchscreen. For driving the display it provides connection
between the CPU video controller and the LCD display module. This PCA also
contains:
power supply circuitry for the LCD display module
a USB hub that is used for communications with the touchscreen controller
and the two front panel USB device ports
the circuitry for powering the display backlight
07276B DCN6418