An apparatus and method of providing a pulse width modulated signal that is responsive to a current are disclosed. A circuit according to aspects of the present invention includes a capacitor to convert a first current to a first voltage on the capacitor during a first time duration and to discharge a second current from the capacitor to change the first voltage to a second voltage during a second time duration. A comparator is also included and is coupled to an output of the capacitor to compare a voltage on the capacitor to a reference voltage during the second time duration to change a pulse width of a periodic output signal in response to an input current.