Abstract: A resonant converter has a switching circuit having a first switch and a second switch, a control circuit and a resonant circuit. The control circuit has a slope sensing circuit providing a slope sense signal based on a voltage variation at the common node of the first switch and the second switch, a slope judge circuit providing a slope judge signal, and a turn-ON control circuit providing a first reset signal to adjust a first dead-time period from turning OFF the first switch to turning ON the second switch based on the slope judge signal, the slope signal, and a current flowing through the resonant tank, and providing a second reset signal to adjust a second dead-time period from turning OFF the second switch to turning ON the first switch based on the slope judge signal, the slope signal, and the current flowing through the resonant tank.

Abstract: A bondable blood-friendly polymer is a terpolymer or a quadripolymer at least formed by polyethylene glycol alkyl ether acrylate or polyethylene glycol alkyl ether methacrylate (I), and zwitterionic acrylic ester or zwitterionic methacrylic ester (II), and acrylic acid or a methacrylate derivative with an epoxypropyl group, an isocyanate group, a trialkoxy silane, a hydroxyalkyl group, a propargyl group or a quaternary ammonium group (III). In the present invention, the blood-friendly polymer with a potentially-bondable group has the following advantages: although the water insolubility thereof is implemented by using the hydrophobicity physical effect of an existing higher alkyl acrylate linkage, the blood friendliness of a coating is reduced due to the existence of a great number of hydrophobic chain links in the polymer; and a physical coating is slowly desolventized from the surface to be ablated in the application process of the physical coating.

Abstract: A switching mode power supply with resonant technology. The switching mode power supply current uses current polarity evaluation to avoid capacitive mode by triggering the capacitive protection if the evaluation indicates that the system will enter capacitive mode.

Abstract: A digital PFC circuit with improved power factor is described. The digital PFC circuit uses a compensation current generating unit and a reference current adjust unit to eliminate the effect of a current flowing through an input capacitor to the input current, so that the input current and the input line voltage of the digital PFC circuit are controlled to be in-phase.

Abstract: A PFC circuit having a switching circuit and a control circuit, the control circuit controls an operation mode of the switching circuit based on an input current and a switching frequency of the switching circuit, when the switching circuit works under a continuous current mode, the switching circuit is turned ON when the input current is less than an OFF current reference signal, and when the switching circuit works under a first discontinuous mode or a second discontinuous mode, the switching circuit is turned ON after a turn ON delay time period when the input current is less than the OFF current reference signal.

Abstract: A power factor correction circuit including a rectifier bridge, an energy storage component, a power switch, a second switch and a control circuit provides reduced THD and improved PF performance under a high input AC voltage.

Abstract: A boost PFC converter, a method and a control circuit used for boost PFC converter are discussed in the present invention. The boost PFC converter decreases the switching frequency when a line voltage is around zero, so that the whole operating efficiency is not decreased.

Abstract: A power factor correction circuit including a rectifier bridge, an energy storage component, a power switch, a second switch and a control circuit provides reduced THD and improved PF performance under a high input AC voltage.

Abstract: A switching regulator that decreases power loss and resolves thermal issues by jumping its switching frequency to a maximum frequency when its load reaches a peak load.