7 PICOSCALE CONTROL GUI
7.5.2 Arbitrary Signal Generator
Figure 7.17: Configuration Menu of the Arbitrary Signal Generators. In this example a frequency
modulation was uploaded as customized signal shape.
The
PICO
SCALE
offers basic signal generator functionality with
sine, square and sawtooth shapes.
Additionally, custom shapes can be uploaded as CSV
fi
les.
I
n the con
fi
guration panel, see
fi
g.
7.17, you can con
fi
gure up to
fi
ve signals (corresponding to
fi
ve DAC interfaces). For each signal
generator you can choose sine, square, sawtooth (P: slow positive ramp, N: slow negative ramp)
or custom shapes in the
Shape
drop-down menu.
The frequency of the signals can be chosen between 1 mHz and 2.5 MHz. Note, that only DAC1
has a high 10 MHz sample rate and may be used to output fast signals. DAC2
–
DAC5 are limited to
200 kHz sample rate. The amplitude can be set in a range between 0 and 1 and the o
ff
set of the
signal can individually be set in a range between -1 and 1, where -1 corresponds to
−10 V
and 1
to
10 V
. For example, a square signal with values between 0 and 5 Volt (i.e. TTL standard) can be
generated with the setting: shape
Square
, amplitude 0.25, o
ff
set 0.25.
When more than one signal generator is used, the signals can be synchronized with each other by
clicking the
Synchronize
button in the upper left part of the
Signal Generator
panel.
I
n the
Custom Shapes
panel, up to
fi
ve custom shapes can be uploaded from CSV
fi
les. The
fi
les
must consist of 2
12
=4096
fl
oat numbers (double, 64 bit) which represent the amplitude of the
signal at each point. Thus the numbers have to be in the range [-1,1]. (Decimal sign is "." and
the individual entries have to be separated by a line break.) The shape of the uploaded signal
is displayed in the graph. The
Edit Shape
button opens the
Custom Shape Editor
which allows to
de
fi
ne a custom signal shape by entering a formula or by uploading it from a CSV
fi
le.
68
PicoScale User Manual
