Oscilloscope Module Block Diagram - HP 75000 C Series Service Manual

The Acquisition PCA attenuatedamplifies each of the four inputs.
The conditioned input signal is then routed
to a
track and hold
circuit. The signal is then multiplexed to an
A/D
Converter where i t
is changed into a digital word. This digital information is stored for
use by the CPU PCA. A replica of the conditioned input signal is also
used for triggering. Additional functions include:
Time base circuit provides the timing signals necessary for
data acquisition.
AC calibrator circuit provides signals for probe compensation,
trigger event, and calibration.
DC calibrator circuit provides a calibration signal.
The CPU PCA contains the control and interface circuits necessary to
direct oscilloscope operations. Control information (COMP or SCPI)
is received from the mainframe controller, and the necessary
instructions are sent to the Acquisition PCA to perform the specific
task. When the digital waveform information is received from the
Acquisition PCA, all the user requested parameters are measured and
routed to the mainframe. Additional functions include:
n ' L and ECL trigger signals from the mainframe are routed
to the Acquisition PCA to perform "external trigger"
functions.
' M ' L
and ECL trigger signals from the oscilloscope are routed
to the mainframe over the backplane trigger bus lines.
Trigger circuit provides a I T L Trigger output signal on the
front panel.
Refer
to
the H P E1426A User's Manual for additional information on
the HP E1426A Oscilloscope.
TOIFROM
MAINFRAME
.
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JI
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1
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1 1
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I I I
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I
INTERNAL
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.
-
TRIGGER
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AC CAL
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Figure
1-2.
Oscilloscope Module Block Diagram
1-2
General Information