MC145443 Overview
however, it is advised that normal precautions be taken to avoid application of any voltage higher than maximum rated voltages to this high impedance circuit. For proper operation it is remended that Vin and Vout be constrained to the range VSS ≤ (Vin or Vout) ≤ VDD). Unused inputs must always be tied to an appropriate logic voltage level (e.g., either VSS or VDD).