Out-of-range voltage detection and protection

A method of operating an integrated circuit, the method comprising:

• generating a first envelope signal of an input signal;
• comparing the first envelope signal to a first reference voltage to generate a first comparison signal;
• generating a control signal based on, at least in part, the first comparison signal;
• and
• selectively opening or closing a first switch based on the control signal, the first switch being coupled between a first protected node and a first protection node.

An integrated circuit comprising:

• a detection circuit comprising:
• a first envelope detector having an output node, the first envelope detector being configured to output a first detected envelope signal on the output node of the first envelope detector;
• and
• a first comparator having a first input node, a second input node, and an output node, the first input node of the first comparator being coupled to the output node of the first envelope detector to receive the first detected envelope signal, the first comparator being configured to output a first comparison signal on the output node of the first comparator, the first comparison signal being based on a comparison of the first detected envelope signal to a signal on the second input node of the first comparator;
• a protected circuit having an internal node;
• and
• a protection circuit comprising a switch coupled between the internal node and a protection node, the switch being controlled to be in an open state or a closed state based on, at least in part, the first comparison signal.