A2 Lcd Assembly - Keysight N9912A Service Manual

Theory of Operation RF Analyzer
Front Panel Group N9912A
system board.
The 5 volts produced is used on the A3 front panel interface board and the A5 system board.
The 3.5 volts produced is used on the A3 front panel interface board, the A5 system board, and the A6 SOM
board.
Both supplies are either on or off together except for power supply sequencing and are controlled by the
System Monitor Microcontroller on the A5 system board.

A2 LCD Assembly

The A2 LCD assembly contains a 6.5-inch, 640 x 480 TFT color LCD with associated drive circuitry and
backlight inverter.
The LCD backlight is created by LED's connected in parallel stacks. Backlight brightness is a function of the
backlight power that ranges from 22 to 27 volts. Refer to "Backlight Power" on page 5-5 for more
information.
The backlight LED's are arranged along the top and bottom edges of the display. There are three stacks on
each edge.
5-6 Service Guide N9912-90003