Tektronix WFM5250, Service Manual

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Theory of Operation
The WFM5250 includes extensive standard capabilities, which can be augmented
by adding various options.
This instrument uses an internal DVI-I monitor for the display, and has an output
to drive an external monitor with the same display. It also has outputs to drive a
serial digital picture monitor.
This theory of operation is based on the High-level Block diagram. (See Figure 1.)
The block diagram re fl ects the physical arrangement of circuit boards, with the
CPU board at the bottom, the Video I/O board in the center, and the FPGA board
at the top. Connectors to the External Reference and Front Panel boards are
shown. Power Distribution is not shown in the block diagram but is covered at
the end of this section.
The primary functions on the CPU board are:
Control processor kernel
Front panel interface
Display backlight
Fan controller
Headphones output and control
USB and network connections
Various secondary power supplies
The primary functions on the Video I/O board are:
SDI Input signal conditioning
HDMI Input signal conditioning
HDMI output (loop-through of input)
Input power conditioning and control
The primary functions on the FPGA board are:
Serial digital input processing
Waveform and picture processing for display
DVI output
Reference input data processing
SDI output generation
WFM5250 Waveform Monitor Service Manual 3