A signal source generates a reference voltage, and a voltage regulator
receives the reference voltage and generates an output voltage and
current. During normal operation, a pass element in the voltage regulator
generates the output voltage, and a sense element generates a sense
voltage. A first voltage detector detects a short-circuit condition using
the sense voltage. A second voltage detector deactivates the pass element
in response to the detection of the short-circuit condition. The second
voltage detector also detects removal of the short-circuit condition and
automatically reactivates the pass element. The first voltage detector
may detect the short-circuit condition by detecting a drop in the sense
voltage. The second voltage detector may detect the removal of the
short-circuit condition by applying a test current to a load. Both the
first and second voltage sensors may not consume any direct current power
during normal operation of the voltage regulator.