A circuit for signaling when an electrical component is consuming excessive power and for protecting the electrical component from the excessive power. The electrical component is connected to a circuit which supplies and measures the current through and measures the voltage drop across the component. The circuit produces a comparison voltage that represents the sum of the current through and voltage across the component, as normalized according to the maximum current and voltage that are expected to be used by the component. The sum of the values of the current and voltage is an approximation to the power consumed by the electrical component. The comparison voltage is compared to a threshold voltage that represents an approximate maximum power level to be sustained by the component. If the first voltage exceeds the threshold voltage, the comparator produces an overpower signal that can be used to cause the current supply to the electrical component to be interrupted.
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