Keysight 9000 Series Service Manual page 73

Chapter 4: Troubleshooting
Acquisition Board Trouble Isolation - Scope Self Tests
If an acquisition board has been removed by a prior procedure, reinstall it.
Power up the oscilloscope and then go under Utilities > Self Test. Select the Scope Self Test option
from the Self Test pull-down menu and then press the Start Test button. If one of these tests fails and
mentions what channel the failure occurred on, replace the acquisition board.
If the error message does not mention a channel, then refer to the discussions below for the test that
failed to see what the test is testing.
Scope Self Tests
Vertical Test Group
• Front End DAC Linearity Test - This test verifies the linearity of each channel's front end DAC. If
the test finds a problem, it will report a failure for the DAC on the associated channel.
• Front End DAC MaxMin Test - This test measures the minimum and maximum output voltage values
of each channel's front end DAC. If the test measures any values that are out of the range of expected
values, it will report a failure for the DAC on the associated channel.
• Otter Register - This test verifies that all of the Otter preamp registers can be correctly written to and
read from. If this test reads any registers whose values are not equal to what they were written to, it
will report a failure for the preamp on the associated channel.
• Overload - This test simulates an overload condition on each channel and verifies that when such a
condition exists it immediately generates an interrupt to the host processor. If such a condition is not
detected properly, the test will report a failure for the associated channel.
Trigger Test Group
• Trigger Lvl DAC Test - This test has not been implemented yet and currently does nothing.
Timebase Test Group
• Timebase Interpolator Test - This test validates the timebase interpolator hardware by verifying that
it is able to produce unique values for different trigger settings. If this test fails, there may be a problem
with the timebase interpolator IC. However, this test has many other hardware dependencies so a
failure from this test cannot necessarily be associated with any specific hardware failure. Try replacing
the acquisition board and see if the test will then pass.
ADC Test Group
• ADC Register Test - This test verifies that all of the ADC registers can be correctly written to and
read from. If the test reads any registers whose values are not equal to what they were written to, it
will report a failure for the ADC on the associated channel.
• ADC Voltage Test Points Test - This test verifies that voltages measured from 32 test points within
the ADC are within their expected range. If any test point is found to be outside of its expected range,
a failure is reported for the ADC containing the associated test point.
Acquisition Memory Test Group
• MBIST - This test checks the embedded memory in each memory controller ASIC for errors. If the
Acquisition Board Trouble
Isolation - Scope Self Tests
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