Abstract: Systems and methods for controlling timing of switches in power regulator/power amplifiers.

Abstract: A power converter has a digital control that interfaces with an analog driver through a simple and efficient signal connection. A single signal may be used to encode frequency and pulse width information to realize a number of control functions based on the digital control algorithms. The functions of analog and digital circuitry are separated to improve flexibility in the power converter, and the interface signal provides a digital-to-analog interface for communicating control information rapidly and efficiently. The arrangement permits realization of a volt-second clamp among other programmable features that were previously set through hard wiring with passive components.

Abstract: A power supply having a transformer-coupled power converter cascaded with a buck power converter. The transformer-coupled power converter operates in a free-running mode at a nearly 100% maximum duty cycle to convert an input voltage to an intermediate voltage. The buck power converter produces a regulated output voltage from the intermediate voltage. The power supply further includes a pulse width modulation (PWM) controller employing leading-edge modulation of complementary control signals used to control buck switches in the buck converter. The PWM controller is synchronized to primary-side free-running switches of the transformer-coupled power converter by a synchronization signal that is fed-forward across an isolation boundary via a signal transformer. The power supply also may also employ a soft-switching technique to reduce switching losses.

Abstract: Leading-edge blanking circuits blank the leading edge of a current sense signal generated by sensing circuitry sensing the current through a switching field-effect transistor. A current sensor is employed to sense the magnitude of gate current being provided to the gate of the switching transistor by a driver circuit. A comparator indicates whether the sensed magnitude of the gate current exceeds a predetermined threshold current. A blanking circuit component, such as a transistor connected to ground, is also used. In one blanking circuit, the blanking component forces the current sense signal to zero when the comparator indicates that the gate current of the switching transistor exceeds the threshold current, and otherwise allows the value of the current sense signal to be determined by the current-sensing circuitry. In another blanking circuit, a latch is interposed between the comparator and the blanking component. The latch generates a blanking control signal to control the blanking component.

Abstract: The addition of an external commutating inductor and two clamp diodes to the phase-shifted PWM full-bridge dc/dc converter substantially reduces the switching losses of the transistors and the rectifier diodes, under all loading conditions. We give analyses, practical design considerations, and experimental results for a 1.5-kW converter with 60-V, 25-A output, operating at 100-kHz clock frequency and 95% efficiency.