This module can be either a Sample & Hold or a Ramp & Hold.
Sample and Hold
If the module is a sample & hold, its output samples (matches) its input (left terminal) when the control input gets a positive transition. The output remains at the voltage level it sampled when the positive edge occurred until another positive edge occurs in the control signal.
Ramp and Hold
If the module is acting as a ramp & hold, its output samples (matches) its input when the input to the control terminal is greater than 0.5 volts (the module is high).