A light emitting device in which a primary light generator, such as a light emitting diode or laser diode, is operable to emit a primary light that is received by a body of wavelength converting material. The DC to DC boost converter includes a switching power converter for receiving the input voltage on an input and converting the input voltage to an output as the DC output voltage in response to pulse control signals. The memory element is programmed to a selected resistance state by application of a selected write current in a selected direction through the cell, wherein a first resistance level is programmed by passage of a write current in a first direction and wherein a second resistance level is programmed by passage of a write current in an opposing second direction.