Chapter 3 Using HP BenchLink/Arb

About Arbitrary Waveforms

Because of this relative amplitude scaling, it is possible to create

 

waveforms that contain unintentional dc offsets. Consider a square wave

 

that ranges from +1 to -0.5. If this waveform is sent to the function

 

generator with a specified output voltage of 1 V peak-to-peak, the square

 

wave will not be centered around 0 V but will have an apparent +0.5 Volt

 

dc offset. The +1 relative amplitude will be scaled to +0.75 V and the -0.5

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relative amplitude will be scaled to -0.25 V.

 

Where possible, your waveforms should range from +1 to -1 in the

 

 

waveform edit window. HP BenchLink/Arb contains a special function to

 

allow you expand the Y values to the maximum.

 

The Y values of the starting and ending points in your waveform can also

 

cause unexpected discontinuities if they are not the same value. The

 

function generator output will ‘jump’ from the ending value to the

 

starting value each cycle. For a smooth waveform output, be sure the

 

starting and ending values are the same.

 

Small discontinuities within the waveform can be removed by smoothing

 

the waveform. These discontinuities are common with waveforms created

 

by freehand or line drawing modes. HP BenchLink/Arb provides a special

 

smoothing function for this purpose.

 

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