Rohde & Schwarz AM 300, Руководство по эксплуатации

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R&S AM300 Arbitrary and Function Generator
Operating manual, 02/2005 6-73 E-1007.9922.12
Application range of
the Square/Square
Low Jitter
waveforms Square
During signal generation in function generator mode (standard waveforms,
e.g. sine) the amplitude information is read out from the waveform memory
using a fixed sample rate of 100 MHz. This gives a fixed time grid of 10 ns for
signal changes. For any frequency the edge of a square signal generally lies
between the sampling times and this results in an error of up to 10 ns, which
is seen in the form of a jitter.
The advantages of this setting are:
the duty cycle can be set
may be combined with any waveform in channel CH2
but:
possible jitter (< 10 ns) at high frequencies
Square Low Jitter
During "Square Low Jitter“ signal generation, the square signal is read out
with a variable sample rate. This rate depends on the set signal frequency
and the sampling times always occur on the edges of the square signals.
The advantages of this setting are:
high frequencies (up
to
50 MHz) can be set
low jitter during signal generation
but:
fixed duty cycle (50 %)
no other waveforms may be set in channel CH2 (for frequency coupling,
6-174)
Note
The Square Low Jitter waveform is generated on both channels when
frequency coupling is on. If a channel is switched from the Square Low Jitter
waveform to another waveform, both channels are changed to the new
waveform.
When frequency coupling is off, the Square Low Jitter waveform is available
in channel CH1 only. Any waveform except pulse may be set in channel CH2.