Abstract: In one form, a switching controller includes a buck controller and a bypass circuit. The buck controller has an input for receiving a variable voltage, an output for providing a buck voltage by switching the variable voltage into an inductive output filter according to a switching signal having a variable duty cycle to regulate a current into a load. The bypass circuit is coupled to the buck controller for comparing the variable duty cycle of the switching signal to a threshold, for activating a bypass signal in response to the variable duty cycle exceeding the threshold, and for subsequently de-activating the bypass signal according to a predetermined algorithm.

Abstract: Detecting faults in circuits driving average-current loads. At least one example is a method comprising: conducting, during a first half-period of a drive cycle, a first current through a first FET to an inductor and an average-current load (e.g., an LED); sensing, during the first half-period, a signal indicative of average current through the first FET; and then conducting, during a second half-period of the drive cycle, a second current through a second FET to the inductor and the average-current load; sensing, during the second half-period, a signal indicative of average current through the second FET; and asserting a fault signal if the signal indicative of average current through the second FET indicates an average current supplied to the average-current load is outside a predetermined range of values.