Abstract: Switch controller circuit (10) for controlling switching in a topology (1) having a first switch (4), a second switch (5), and a switching node (6) coupled therebetween. A driver arrangement (101,104,105) controls the first and second switches (4,5) to alternately open and close, wherein a deadtime period is applied between the opening of one switch (4) and the closing of the other switch (5) in use. A voltage sensor (106) connected to the switching node (6) provides feedback based on a sensed voltage as it transitions between high and low voltage states and sets a length of the deadtime period based on a measured first time period and a multiplier coefficient. The first time period is measured from a time of opening of one of the switches to a time when the sensed voltage transitions through a threshold set between the high and low voltage states.

Abstract: A controller (10) for controlling switching in a multiphase power converter (1) having a plurality of converter bridges (2a, 2b), each associated with a phase. The controller (10) includes a driver block (10a) for generating gate driver signals for controlling power switches (HS1-4, LS1-4) in each of the converter bridges (2a, 2b), an imbalance sensor block (10b) for identifying a power imbalance between the plurality of converter bridges (2a, 2b), and an adjustment block (10c) for adjusting the control of the power switches (HS1-4, LS1-4) in response to the detection of a power imbalance by modifying timing of the generated gate driver signals.

Abstract: Switch controller circuit (10) for controlling switching in a topology (1) having a first switch (4), a second switch (5), and a switching node (6) coupled therebetween. A driver arrangement (101,104,105) controls the first and second switches (4,5) to alternately open and close, wherein a deadtime period is applied between the opening of one switch (4) and the closing of the other switch (5) in use. A voltage sensor (106) connected to the switching node (6) provides feedback based on a sensed voltage as it transitions between high and low voltage states and sets a length of the deadtime period based on a measured first time period and a multiplier coefficient. The first time period is measured from a time of opening of one of the switches to a time when the sensed voltage transitions through a threshold set between the high and low voltage states.

Abstract: A method of making optical devices includes applying an energy sensitive protective material and an energy sensitive advanced optical material to a surface. The surface can be on the optical device or on a carrier, such as a thin sheet, to be applied to the optical device. Light energy is applied through a special production filter to cure the energy sensitive protective material on the surface while blocking light energy outside a selected wavelength spectrum from reaching the material. A portion of the optical device can then be masked, and light energy outside the spectrum filtered by the special production filter can be applied to activate the unmasked portion of the advanced optical material. The special production filter allows curing of the protective material using light energy in a limited (e.g., visible) spectrum so that the advanced optical material can be activated using light energy in the ultraviolet spectrum.

Abstract: A system for selectively enabling or disabling an optical device, such as an optical disc, includes an optical blocking material bonded or otherwise integrated into the optical device. In a specific embodiment, the optical blocking material includes a dye, such as an energy-sensitive dye. The optical blocking material is initially applied to the optical device during production using a spin coating or other suitable technique. An area of the optical device that will prevent a function of the device is then masked, and sufficient energy is applied to the unmasked area to activate the optical blocking material of the unmasked area while leaving the masked area unactivated. In a specific embodiment, the masked area corresponds with a lead-in area of an optical disc. The optical blocking material of the masked area remains non-transparent to disable the optical device until a second application of energy at a retail location.