Programming instructions

Voltage Hysteresis Block
 National Instruments Corporation 1-35 Multisim Component Reference Guide
Changing frequency changes the area. Therefore, in the case of lower frequencies, output rises
faster.
1.34 Voltage Hysteresis Block
This component is a simple buffer stage that provides hysteresis of the output with respect to
the input. ViL and ViH specify the center voltage or current inputs about which the hysteresis
effect operates. The output values are limited to VoL and VoH. The hysteresis value, H, is
added to ViL and ViH in order to specify the points at which the slope of the hysteresis
function would normally change abruptly as the input transitions from low to high values. The
slope of the hysteresis function is smoothly varied whenever ISD is set greater than zero.
This component can be used to simulate a non-inverting comparator in which the comparison
threshold is changed each time the input crosses the threshold in effect at that instant. As the
output changes state (high to low or low to high), the threshold voltage is changed internally
in such a manner that the input must continue to change until it reaches the new threshold.
In the example circuit shown below, the hysteresis value is set to 5V. This means that the two
comparison thresholds at which the output changes are +5V and -5V.
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