Agilent Technologies Agilent 33500 Series, Руководство по эксплуатации и обслуживанию

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FUNCtion Subsystem
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The default "BOTH" keyword is optional and allows simultaneous control of the leading and trailing edges of the
PRBS waveform.
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The edge time applies to both the rising and falling edges, and represents the time between the 10% and 90%
thresholds of each edge.
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The specified edge time must fit within the specified period. The instrument will limit the edge time as needed to
accommodate the specified bit rate. From the remote interface, a "Settings conflict" error will also be generated.
[SOURce[1|2]:]FUNCtion:PULSe:DCYCle {< percent >|MINimum|MAXimum}
[SOURce[1|2]:]FUNCtion:PULSe:DCYCle? [{MINimum|MAXimum}]
Sets pulse duty cycle.
Parameter Typical Return
0 to 100, limited as described below; default 10 +5.00000000001
Set duty cycle to 50%:
FUNC:PULS:DCYC 50
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The FUNCtion:PULSe:DCYCle and FUNCtion:PULSe:WIDTh commands affect the same parameter. In some appli-
cations, it is natural to adjust pulse width directly (in seconds); in others, adjusting duty cycle seems more natural.
When frequency is adjusted, if pulse width was most recently adjusted as duty cycle on the front panel, then duty
cycle will be kept constant as frequency or period changes. However, if pulse width was the last setting, then pulse
width will be kept constant as frequency or period changes. See
FUNCtion:PULSe:HOLD .
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The pulse duty cycle is defined as:
Duty Cycle = 100 x Pulse Width ÷ Period
Pulse width is the time from the 50% threshold of a pulse's rising edge to the 50% threshold of the next falling
edge.
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The pulse duty cycle range is 0 percent to 100 percent. However, the pulse duty cycle is limited by minimum pulse
width and edge time restrictions, which prevent you from setting exactly 0 percent or 100 percent. For example,
for a 1 kHz pulse waveform, you are typically restricted to pulse duty cycles in the range 0.002 percent to 99.998
percent, limited by the minimum pulse width of 16 ns.
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Restrictions Based on Pulse Width: The specified pulse duty cycle must conform to the following restrictions deter-
mined by the minimum pulse width (Wmin). The instrument will adjust pulse duty cycle as needed to accom-
modate the specified period. From the remote interface, a "Settings conflict" error will also be generated.
Duty Cycle
≥
(Wmin / Period) X 100
and
Duty Cycle
≤
(1 – Wmin / Period) X 100
where Wmin = 20 ns
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Restrictions Based On and Affecting Edge Time: The specified pulse duty cycle may affect the edge time. The edge
time is adjusted first, and then the duty cycle is adjusted to accommodate the specified period, conforming to the
following restriction. From the remote interface, a "Settings conflict" error will also be generated.
Agilent 33500 Series Operating and Service Guide 219