Methods and apparatus for detecting zero-volt crossing in a field-effect transistor. A comparator compares a drain-to source voltage of the transistor to a threshold voltage. A gate voltage signal of the transistor is provided to a clock input of the comparator such that said gate voltage signal is used to latch a result of said comparison to an output of the comparator. A control function with respect to the transistor is performed based on the value of the comparator output.