Tektronix TDSUSB2, Руководство пользователя

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Reference
Note: Use the Alt key with only the first keystroke. Release the Alt key before you
press the final key. For example, to use the shortcut key AltF+D, press the Alt
and F keys together. Release the keys and then press D.
USB2.0 Specifications
This section gives the USB2.0 values for measurements for Low, Full and High
speed signals.
Low Speed
Table 31. Low Speed measurements
USB Limits User Configure Limits References*
Measure-
ments
Max Min Max. range Min. range
Cross-Over
Voltage 2.0 V 1.3 V 1.6-2.4 V 1.04-1.56 V Chapter 7, Table 7-7,
Section 7.1.2.1
Signal Rate 1.5225 Mbps 1.4775 Mbps 1.5675-1.881
Mbps
1.146-
1.4325
Mbps
Chapter 7, 7.1.11
Consecutive
Jitter <25 ns N/A 20-30 ns N/A Chapter 7, 7.1.13.1
Paired Jitter <10 ns N/A 8-12 ns N/A Chapter 7, 7.1.13.1
Rise Time 300 ns 75 ns 240-360 ns 60-90 ns Chapter 7, 7.1.2.1
Fall Time 300 ns 75 ns 1240-360 ns 60-90 ns Chapter 7, 7.1.2.1
EOP Width 1.5e-6 s 1.25e-6 s 1.2-1.8 1-1.5 ns Chapter 7, 7.1.13.2.1
* The References Section refers to the chapter numbers in the ‘Universal Serial
Bus Specifications Revision 2.0-2000’.
Note 1: Results within the USB limit lead to a PASS condition. Results within the
waiver limits, but outside USB limits lead to a Conditional PASS. Results within
the user configured limits lead to PASS. When user configure limits is selected,
you can view only the result details.
Note 2: Testing at Tier 6 leads to a PASS. Testing at Tier 5 and 4 leads to a
Conditional PASS that is a Pass within the waiver limits. Testing at Tier 1 to 3
leads to a FAIL.
166 TDSUSB2 Universal Serial Bus Measurement Package