Tektronix TPS2012B, Руководство пользователя

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Appendix A: TPS2000B Speci fi cations
Table 5: Trigger Speci fi cations (cont.)
Characteristics Description
Signal Formats and Field
Rates, Video Trigger Type Supports NTSC, PAL, and SECAM broadcast systems for any fi eld or any line
Holdoff Range 500 ns to 10 s
1 Available only on a 4-channel oscilloscope.
2
TPS2024B only.
Table 6: Pulse Width Trigger Speci fi cations
Characteristics Description
Pulse Width Trigger modes Trigger when < (Less than), > (Greater than), = (Equal), or ≠ (Not Equal); Positive pulse or
Negative pulse
Pulse Width Trigger Point Equal: The oscilloscope triggers when the trailing edge of the pulse crosses the trigger level.
Not Equal: If the pulse is narrower than the speci
fi ed width, the trigger point is the trailing edge.
Otherwise, the oscilloscope triggers when a pulse continues longer than the time speci fi ed as
the Pulse Width.
Less than: The trigger point is the trailing edge.
Greater than (also called time-out trigger): The oscilloscope triggers when a pulse continues
longer than the time speci
fi ed as the Pulse Width.
Pulse Width Range Selectable from 33 ns to 10 s
Pulse Width Resolution 16.5 ns or 1 part per thousand, whichever is larger
Equal Guardband t > 330 ns: ±5% ≤ guardband < ±(5.1% + 16.5 ns)
t ≤ 330 ns: guardband = ±16.5 ns
Not Equal Guardband t > 330 ns: ±5% ≤ guardband < ±(5.1% + 16.5 ns)
165 ns < t ≤ 330 ns: guardband = -16.5 ns ÷ +33 ns
t ≤ 165 ns: guardband = ±16.5 ns
Table 7: Trigger Frequency Counter Speci fi cations
Characteristics Description
Readout Resolution 6 digits
Accuracy (typical) ±51 parts per million including all frequency reference errors and ±1 count errors
Frequency Range AC coupled, 10 Hz minimum to rated bandwidth
Signal Source Pulse Width or Edge Trigger modes: all available trigger sources
The Frequency Counter measures trigger source at all times in Pulse Width or Edge modes,
including when the oscilloscope acquisition is halted due to changes in the run status, or acquisition
of a single shot event has completed.
Pulse Width Trigger mode: The oscilloscope counts pulses of signi
fi cant magnitude inside the
250 ms measurement window that qualify as triggerable events, such as narrow pulses in a PWM
pulse train if set to < mode and the width is set to a relatively small time.
Edge Trigger mode: The oscilloscope counts all edges of suf
fi cient magnitude and correct polarity.
Video Trigger mode: The Frequency Counter does not operate.
TPS2000B Series Digital Oscilloscope User Manual 127