The characteristic behavior of a diode lies in its response to an applied voltage. The voltage drop is a measure of energy lost across the junction of the diode. This is represented by a forward voltage (VF). When the applied forward bias voltage is greater than this value the current increases exponentially. The load that the diode can carry is represented by a forward current (IF). Below the forward voltage there is an insignificant current across the junction. The reverse voltage (VR) is blocked and the voltage required to cause a significant increase in current beyond the reverse current (IR), also known as leakage current, to exist is a potential several times larger than the forward voltage, known as the breakdown voltage (VBR). This behavior allows the junction to exhibit two states, ON when the potential is greater than the forward voltage and OFF when the potential is less than the forward voltage, so long as the reverse breakdown voltage is not exceeded.