Stanford Research Systems DS345, Manual

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Arbitrary Waveform Composer
7-4
DC value (in Volts) to which the segment should be set. The segment can be
as short as one point and as long as the whole waveform.
Redraw Redraws the waveform and zooms out to display the full waveform.
Mirror Mirrors the waveform about 0 Volts (multiplies every data point by -1).
Amplitude Sets the amplitude of the waveform. Any value in the range 0.01 Vpp to 10
Vpp may be entered. To add an offset to the waveform, the
Math selection in
the waveform menu should be used. Note that |V
ac peak
| + |V
dc
|
≤
5 V. This
command only changes the data in AWC's waveform database. The waveform
must be reloaded into the DS345 for the change to take effect.
Waveform menu The Waveform menu is the key to creating new waveforms and modifying
existing ones. Seven conventional waveforms can be created: Sine, Square,
Triangle, Saw, Exponential, Exponentially Damped Sine wave, and Pulses.
The Math menu allows the user to perform math operations on any waveform
on the screen. All waveforms are created with zero DC offset. An offset may
be added to the waveform using the math function. Waveform creation may be
aborted by pressing escape (ESC) on the keyboard.
Sine
Square
Triangle
Saw
Three parameters must be entered for these waveforms. The waveform can
be between 8 and 16300 points long, and can contain a specified number of
complete sine wave cycles. The maximum number of cycles is limited so that
each cycle has at least 8 points. The waveform amplitude in Volts peak-to-
peak is also entered. The waveform will have zero DC offset.
Exponential Produces an exponentially shaped pulse. The user is asked for three
parameters. The waveform can be between 8 and 16300 points long. The
exponential damping factor (b) is then set. The waveform will be reduced or
increased by a factor exp(b) at its endpoint, where b is limited to the range -50
to 50. The waveform amplitude in Volts peak-to-peak is entered. The
waveform will have zero DC offset level.
Damped Sine This selection produces an exponentially damped sinewave. Four parameters
are entered. The number of points, number of cycles, and amplitude are the
same as for the normal sine function. The fourth parameter is the damping
factor (b). The waveform will be reduced or increased by a factor exp(b) at its
endpoint, where b is limited to the range -50 to 50.
Pulse This selection generates a pulse train. The pulse train can have between 1
and 100 transitions (state changes). AWC first asks for the number of points in
the waveform, and the waveform amplitude. The user is then asked for the
transition locations (pulse edges) in the waveform. The first transition always
has a positive slope. If a negative starting transition is needed, apply the
mirror function after the waveform is created.
Math The math selection applies mathematical operations to the current waveform.
This selection is disabled when there is no waveform. The user may mirror the
waveform (multiply by -1), or may add, subtract, or multiply the waveform by a
constant, sine, square, triangle, sawtooth, or exponential wave. These
operations may take place over the entire waveform or just a segment.