Module Overviews (Dpo7000 Series, Dsa/Dpo70000B/C Series) - Tektronix MSO70000 Series Service Manual

Theory of Operation
Logic Conventions

Module Overviews (DPO7000 Series, DSA/DPO70000B/C Series)

Input Signal Path
MSO70000/C, DSA70000B/C, DPO70000B/C, DPO7000, MSO5000, DPO5000 Series
This section describes the electrical operation of the instrument. The following
figures show the module interconnections. (See Figure 2-1 on page 2-4.)
The instrument contains many digital logic circuits. This manual refers to these
circuits with standard logic symbols and terms. Unless otherwise stated, all logic
functions are described using the positive-logic convention: the more positive of
the two logic levels is the high (1) state, and the more negative level is the low
(0) state. Signal states may also be described as "true" meaning their active state
or "false" meaning their nonactive state. The specific voltages that constitute a
high or low state vary among the electronic devices.
Module overviews describe the basic operation of each functional circuit block.
A Microsoft Windows processor system is the primary controller of the
instrument. The instrument features an XGA resolution flat-panel display, a
transparent touch screen, and a front-panel with direct access to commonly used
instrument functions. You can also make complete use of the instrument with a
mouse and keyboard.
A signal enters the instrument through a connection to the input connector on
the front panel.
Acquisition Board. The acquisition board conditions the input signals and
converts them to digital signals, then processes the data into a form that is handled
by the display system. The acquisition system includes the multi-source trigger
system, a timebase, and acquisition control circuitry, as well as a calibration
reference system for internal calibration purposes. The acquisition board is
located in the bottom compartment of the instrument. All input channels feature
a probe interface system with the ability to recognize the probe type for proper
unit display and for calibration out to the probe tip.
Processor System. The processor system contains a processor board with
microprocessor that controls the entire instrument. The basic configuration
supports input channels, provides an external trigger input, a trigger output, and a
probe compensation output.
Each acquisition channel is equipped with a processor that uses its own host
interface which communicates with the command interface processor.
2–1