For a PWM controller chip in a voltage converter to switch a pair of high
side and low side switches connected with a phase node therebetween, a
circuit comprises a sense resistor connected between a multi-function pin
on the PWM controller chip and the phase node, and an enable arrangement,
a power sensing arrangement, and an over-current protection arrangement
to detect the voltage on the multi-function pin for accomplishing enable
function, power sensing, and over-current protection, respectively.