Specifications

Chapter 7: Theory of Operation
Front Panel Assembly
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Front Panel Assembly
The front panel assembly consists of an LCD display board with backlight; a touch
screen and touch controller; an on/off board; and a keyboard assembly, which is two
boards that sit with one behind the other, connected with a pair of 60- pin board- to-
board connectors.
On/Off Board
The on/off board interfaces with the motherboard to provide the on/off switch function,
and with the backplane to provide the probe compensation output. Power indicator
LEDs backlight the on/off button and are driven by the motherboard. The probe
compensation lugs connect to the calibrator output on the backplane through an SMB
connector coax cable. An ESD protection diode sits on the on/off board, connecting the
signal and ground probe compensation lugs.
Keyboard Assembly
The two boards that comprise the keyboard assembly work together to provide the main
user interface to the instrument, and power and communication to the probe interface.
The rear board has all the external connectors, AutoProbe II circuits for probe power
and probe control, LED backlight power supply, touchscreen controller, and knobs. The
front board has the buttons, FPGA, and LEDs.
Figure 7- 9 shows a block diagram of the oscilloscope keyboard assembly.
Figure 7-9 Keyboard Assembly Block Diagram