A method to prevent ringing in Discontinuous Conduction Mode of a boost converter for a white LED driver, comprising the following steps: providing a high-voltage WLED asynchronous boost converter, driving one or more WLEDs connected in series, wherein the boost converter comprises a port for an input voltage (VBAT), an inductor, a diode, a power switch, wherein the inductor, the diode, and the power switch are all connected to a node; sensing a fast falling edge of the voltage at the node between inductor and power switch by a Edge detector circuit, wherein a sense capacitor of the Edge detector circuit, attached to the node between inductor and power switch, receives input from the node and signals the fast falling edge to a bootstrap circuit, which controls a HV bulk coil switch system in order to immediately initiate shorting the inductor when in Discontinuous Mode of Operation; shorting the inductor when the current through the inductor reaches zero during DCM mode by the HV bulk coil switch circuit across the inductor, wherein the HV bulk coil switch circuit comprises two identical HV enhancement NMOS devices (N1, N2) with bulk switch system sharing a bulk, which is connected to the drain of an NMOS transistor; and turning on the bulk coil switch circuit, configured to short the inductor when in Discontinuous Mode of Operation, by lifting the gates of the two identical HV enhancement NMOS devices (N1, N2) of the coil switch circuit above the input voltage level (VBAT) using a Boost Strap system comprising a capacitor (Cp) and an amplifier wherein, when the bulk coil switch is turned on, a charge of the capacitor Cp is reversed into the gate capacitances of the two identical HV enhancement NMOS devices (N1, N2) to a voltage level above the VBAT level and turning hence on the coil switch circuit. providing a high-voltage WLED asynchronous boost converter, driving one or more WLEDs connected in series, wherein the boost converter comprises a port for an input voltage (VBAT), an inductor, a diode, a power switch, wherein the inductor, the diode, and the power switch are all connected to a node; sensing a fast falling edge of the voltage at the node between inductor and power switch by a Edge detector circuit, wherein a sense capacitor of the Edge detector circuit, attached to the node between inductor and power switch, receives input from the node and signals the fast falling edge to a bootstrap circuit, which controls a HV bulk coil switch system in order to immediately initiate shorting the inductor when in Discontinuous Mode of Operation; shorting the inductor when the current through the inductor reaches zero during DCM mode by the HV bulk coil switch circuit across the inductor, wherein the HV bulk coil switch circuit comprises two identical HV enhancement NMOS devices (N1, N2) with bulk switch system sharing a bulk, which is connected to the drain of an NMOS transistor; and turning on the bulk coil switch circuit, configured to short the inductor when in Discontinuous Mode of Operation, by lifting the gates of the two identical HV enhancement NMOS devices (N1, N2) of the coil switch circuit above the input voltage level (VBAT) using a Boost Strap system comprising a capacitor (Cp) and an amplifier wherein, when the bulk coil switch is turned on, a charge of the capacitor Cp is reversed into the gate capacitances of the two identical HV enhancement NMOS devices (N1, N2) to a voltage level above the VBAT level and turning hence on the coil switch circuit.