The MAX4533 quad, single-pole/double-throw (SPDT), fault-protected analog switch is pin-compatible with the industry-standard MAX333 and MAX333A. The MAX4533 features fault-protected inputs and Rail-to-Rail signal handling. The normally open (NO_ ) and normally closed (NC_ ) terminals are protected from overvoltage faults up to 25V with power on and up to 40V with power off. During a fault condition, NO_ and NC_ become high impedance with only nanoamperes of leakage current flowing to the source. In addition, the output (COM_) clamps to the appropriate polarity supply rail and provides up to 10mA of load current. This ensures unambiguous rail-to-rail outputs when a fault occurs.