Signal level detection and overrange signal limiter and clamp for electronic circuits

An apparatus comprising:

• a detector circuit electrically coupled between a signal source and a second circuit, the signal source generating a first signal, the detector circuit comparing the first signal with first and second threshold values and generating a control signal when the detected level of the first signal exceeds the first threshold value or falls below the second threshold value;
• and
• a clamping switch electrically coupled to receive the control signal from the detector circuit, the clamping switch comprising a multi-terminal active device;
• wherein the control signal controls a state of the clamping switch such that the clamping switch clamps a level of a signal applied to the second circuit when the detected level of the first signal exceeds the first threshold value or falls below the second threshold value.

A method comprising:

• comparing a level of a first signal generated by a signal source to a first threshold value;
• generating a first control signal if the level of the first signal exceeds the first threshold value;
• and
• using the first control signal to activate a clamping switch comprising a multi-terminal active device, wherein the first control signal is provided to a first terminal of the multi-terminal active device and controls a value of a variable impedance between second and third terminals of the multi-terminal active device;
• wherein activation of the clamping switch clamps a value of a signal applied to a circuit under protection (“CUP”) to approximately the first threshold value.