A front-end architecture system includes a system voltage input and a controller electrically connected to the system voltage input. The controller is configured and adapted to provide a voltage output to at least one controller output. The controller includes a single-ended primary-inductor converter (SEPIC) and a monitoring and switchover circuit. A method for controlling a voltage input to a low-voltage power supply (LVPS) includes receiving a system voltage input with a controller, wherein the controller includes a single-ended primary-inductor converter (SEPIC) and a monitoring and switchover circuit. The method includes providing a voltage output of the controller to at least one controller output. The method includes receiving the voltage output with a low-voltage power supply (LVPS) electrically connected to the at least one controller output.

Various embodiments may relate to a load driving circuit and an illumination apparatus including the same. The load driving circuit includes a Single-Ended Primary Inductor Converter (SEPIC) converter adapted to convert an input system voltage into a DC output voltage, and a BUCK converter 200 adapted to regulate a current and provide the regulated current to a load. The load driving circuit further includes a first diode and a second diode which are connected so that the SEPIC converter and the BUCK converter share one switch. According to various embodiments, it is possible to obtain constant current output characteristics and high power factor with a simple circuit structure and a low cost.

A DC-DC converter system (1, 1′) according to the invention is provided with an input (In) for feeding in an input voltage (U_in), a step-up controller section (2) for increasing the input voltage (U_in) in a controlled manner to a controlled first output voltage (U_out1) and for providing the first output voltage (U_out1) at a first supply output (Out1), and a voltage conversion section (3) for converting the input voltage (U_in) into a second output voltage (U_out2) in a manner controlled by a control device of the step-up controller section (2) and for providing the second output voltage (U_out2) at a second supply output (Out2). The DC-DC converter system (1) according to the invention having two supply outputs (Out1, Out2) is based on an expansion of a step-up controller with a SEPIC circuit, wherein the DC-DC converter system comprises only a single control device (S1) and a switching device (T1) which can be controlled by the control device.

An isolated step-up converter having first and second stages is described herein. The second stage can provide either DC or AC output based on the various topologies described. Resonance inductors and capacitors are used and tuned to a commutation frequency in some embodiments. Capacitors and inductors are also used in the first stage.

In accordance with an embodiment, a method of operating a switched-mode power includes turning on an output switch of the switched-mode power converter coupled to a supply output port of the switched-mode power converter, where an output switch current flows to the supply output port through the output switch in a first direction after turning on the output switch. The method further includes turning off the output switch a first period of time after the output switch current changes polarity from the first direction to a second direction opposite the first direction.

A method and apparatus for generating a pulse width modulation (PWM) control signal generates a sawtooth ramp signal at a first frequency under standard operating conditions using a ramp generator, and generates a sawtooth ramp at a second frequency under alternative operating conditions. The sawtooth ramp is combined with an error threshold by a PWM controller to generate a square wave PWM control signal. The error threshold is adjusted simultaneous with adjusting the frequency of the sawtooth ramp, thereby preventing either a voltage overshoot and a voltage undershoot.

According to one aspect, embodiments herein provide a DC-AC inverter comprising a DC-DC converter portion, an inverter portion, a clamp circuit, a controller configured to operate, in a first mode, the DC-DC converter portion to convert input DC power into DC power having a desired voltage level at a first polarity and the inverter portion to provide output power having the desired voltage level at the first polarity to the output, operate, in a second mode, the DC-DC converter portion to convert the input DC power into DC power having a desired voltage level at a second polarity and the inverter portion to provide output power having the desired voltage level at the second polarity to the output; and operate, in a third mode, the clamp circuit to drive voltage at the output to zero and to store energy discharged by a load capacitance in an energy storage device.

Embodiments of the present invention provide a switching circuit. The circuit comprises: a charging sub-circuit, which has a first input end and an output end; a switching sub-circuit, which has a first end, a second end, and a control end, wherein the control end of the switching sub-circuit is connected to the output end of the charging sub-circuit; and a function sub-circuit, which is connected to the first end or the second end of the switching sub-circuit, and has a first node, wherein an operating voltage of the first node is higher than an input voltage of an input power supply, the switching sub-circuit comprises one or more NMOS switches, and the first input end of the charging sub-circuit is connected to the first node.

A method for generating a pulse width modulation (PWM) control signal includes generating a sawtooth ramp signal at a first frequency under standard operating conditions using a ramp generator, generating a PWM square wave having a rising edge at a falling edge of the sawtooth ramp signal and a falling edge when the sawtooth ramp signal exceeds an error threshold, adjusting the frequency of the sawtooth ramp in response to a changed operating parameter of the ramp generator, and adjusting a peak input voltage of the ramp generator simultaneous with adjusting the frequency of the sawtooth ramp, thereby preventing one of a voltage overshoot and a voltage undershoot.

A connected compact battery charger for charging a battery comprising: a microprocessor; a set of terminals operatively coupled to said microprocessor and configured to electrically couple with an automotive battery; and an internal lithium ion battery, wherein the internal lithium ion battery is a lithium ion battery, wherein a single-ended primary-inductor converter may be configured to receive an input voltage of 5 VDC to 20 VDC and output a predetermined DC charge voltage to said internal lithium ion battery.