Keysight Infiniium 8000 Series, Руководство по обслуживанию

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Chapter 3: Testing Performance
To verify threshold accuracy
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To verify threshold accuracy
This test verifies the data channel threshold accuracy specifications of the Mixed Signal
Oscilloscopes. The threshold voltage is the digital channel input voltage at which a bit
transitions from logic 0 to logic 1 (low- to- high transition) or from logic 1 to logic 0
(high- to- low transition).
Specification:
Threshold accuracy = ±
(100 mV + 3% of threshold setting).
When to Test You should perform this test every 24 months or after 4000 hours of
operation, whichever comes first.
What to Test Use these instructions to test the threshold accuracy of digital channels
D15- D0.
Verifying Test Results After each threshold test, record the voltage reading in the
Performance Test Record at the end of this chapter. If the voltage readings are within
the limits in the Performance Test Record, the test passes.
Let the Equipment Warm Up Before Testing For accurate test results, let the test
equipment and the oscilloscope warm up at least 30 minutes before testing.
Equipment Required
Test Threshold Accuracy only on the Mixed-Signal Oscilloscopes (MSOs)
This test can only be performed on oscilloscope models that have digital channels.
Equipment Critical Specifications Recommended Model/Part
Digital Multimeter 100
μ
V resolution, DC voltage measurement
accuracy better than ±0.01% of reading
Keysight 34401A
DC Signal Source Voltage range ±5.5 V
Voltage setting resolution ±5 mV Keysight 3631A or Fluke 5820A
Adapter BNC Tee (m)(f)(f) Keysight 1250-0781
Coaxial Cable
(Qty. 2) Length ~ 1 m
BNC (m) connectors on both ends
50
Ω
characteristic impedance
Keysight 8120-1840
Digital Cable
Assembly No substitute Keysight 54826-61605
(Included in 54826-68701 logic probe kit)
Probe Tip Assembly No substitute Keysight 54838-61608
Probe Grounds
(Qty. 5) No substitute Keysight 5959-9334
Adapter or BNC
Breakout BNC (f) to 20 AWG leads Pomona 4969
Header Strip
≥
0.1 inch (2.54 mm) spacing
≥
32 pins
Waldom Electronics 10-89-1161
Wire Strips
(Qty. 2) ~1.5 inches (4 cm) in length
20 AWG
Adapter BNC (f) to dual banana Keysight 1251-2277