Abstract: A dual-input power converter comprises two power stages using a common low-side element, a first input for coupling a first input voltage to the first power stage, a second input for coupling a second input voltage to the second power stage, and a controller for driving the first and second power stages to convert the first or second input voltage to an output voltage.

Abstract: In an apparatus for over-voltage and over-current protection for a step-up current-mode converter including an inductor connected via a phase node to a switch that is switched by a control signal to convert an input voltage to an output voltage, a controller has a multiplexed pin, and a resistor and a capacitor are connected in parallel between the multiplexed pin and the phase node. In an over-voltage protection mode, the controller senses the voltage on the multiplexed pin, and in an over-current protection mode, the controller supplies a current to flow through the resistor and senses the voltage on the multiplexed pin.

Abstract: The present invention discloses a power supply comprising: a switching regulator circuit converting an input voltage to an intermediate voltage; a low dropout linear regulator circuit converting the intermediate voltage to an output voltage so as to supply a load current to a load; and a feedback control circuit which increases the noise filtering effect of the low dropout linear regulator circuit when the load current increases.

Abstract: An offset current independent sense circuit is switchable between a store state and a sense state. In the store state, the sense circuit stores an offset current to a capacitor, and the influence of the offset current is eliminated by a transistor to regenerate the offset current based on a signal provided by the capacitor in the sense state.

Abstract: A plurality of switches, an inductor and two capacitors are configured to be a boost-inverting converter. To operate the converter in a boost-inverting mode, a control apparatus and method switch the switches such that the inductor is energized in a first phase, the first capacitor is discharged to produce an inverting voltage in a second phase, and the capacitor Cout1 is discharged to produce the inverting voltage and the second capacitor is charged to produce a boost voltage in a third phase. Therefore, the boost-inverting converter has lower peak inductor current and less power loss, and the limitation to the switch design for the boost-inverting converter is relaxed.

Abstract: An offset current independent sense circuit is switchable between a store state and a sense state. In the store state, the sense circuit stores an offset current to a capacitor, and the influence of the offset current is eliminated by a transistor to regenerate the offset current based on a signal provided by the capacitor in the sense state.

Abstract: An offset current independent sense circuit is switchable between a store state and a sense state. In the store state, the sense circuit stores an offset current to a capacitor, and the influence of the offset current is eliminated by a transistor to regenerate the offset current based on a signal provided by the capacitor in the sense state.

Abstract: A method, which is for determining switching state of a transistor-based switching device that includes a set of transistors, includes the steps of: applying a bias voltage to a transistor having a fastest response so as to dispose the transistors in the set in a desired transistor state; detecting a voltage level at a transistor having a slowest response to the bias voltage; and comparing the detected voltage level with a predetermined threshold voltage level in order to determine the switching state of the switching device. A transistor-based switching device is also disclosed.

Abstract: A high efficiency power converter comprises a boost converter for converting an input voltage to a first voltage on a first output, a buck converter for converting the input voltage to a second voltage on a second output, a linear regulator for converting the first voltage to a third voltage on the second output when the second voltage is lower than a first threshold, and a voltage detector for detecting the input voltage for preventing a reverse current flowing from the second output to the buck converter when the input voltage is lower than a second threshold.

Abstract: In a delay cell, a capacitor and a current mirror are configured to have an equivalent capacitance, and the current mirror establishes a capacitor displacement current to charge the capacitor, by which it is equivalently generated a much smaller current to charge the capacitor for a desired delay time. Therefore, the actual layout is much reduced in size for the capacitor, and the capacitor could be implemented within a chip.

Abstract: In a capacitor charger, a transformer has a primary winding connected between an input voltage and a switch for generating a primary current flowing through the primary winding by switching the switch to thereby induce a secondary current flowing through a secondary winding of the transformer and a secondary voltage tapered from the secondary winding, a control apparatus and method adjusts the on-time period for the switch in response to the input voltage. The charging time and charging current are independent of the input voltage, and there is no power loss resulted from current sense to the primary current.

Abstract: A direct current voltage boosting/bucking device includes a direct current voltage boosting circuit and a low drop-out (LDO) linear voltage converting circuit. The direct current voltage boosting circuit boosts an input voltage so as to generate an output voltage higher than the input voltage. The LDO linear voltage converting circuit converts the output voltage into a load voltage that is to be provided to a load, and controls the direct current voltage boosting circuit in accordance with a feedback signal from the load such that the output voltage and the load voltage have a minimum drop-out voltage differential therebetween and such that current flow through the load is maintained at a determined level.

Abstract: A pulse width modulation (PWM) Regulator System with automatically switching pulse skipping mode (PSM) is disclosed. The PWM regulator system comprises a PWM regulator, a PSM switching module and a pulse generator. The PWM regulator converts the input voltage by PWM. The PSM switching module determines to enter or exit the PSM. The pulse generator adaptively produces pulse signal for the switching regulator to operate in PSM.

Abstract: A direct current voltage boosting/bucking device includes a direct current voltage boosting circuit and a low drop-out (LDO) linear voltage converting circuit. The direct current voltage boosting circuit boosts an input voltage so as to generate an output voltage higher than the input voltage. The LDO linear voltage converting circuit converts the output voltage into a load voltage that is to be provided to a load, and controls the direct current voltage boosting circuit in accordance with a feedback signal from the load such that the output voltage and the load voltage have a minimum drop-out voltage differential therebetween and such that current flow through the load is maintained at a determined level.

Abstract: In a fly-back voltage converter that includes a transformer to transform a primary current to a secondary current and a switch serially coupled to the primary winding to switch the primary current in response to a control signal, a detection signal is produced by comparing the secondary current with two threshold values after the primary current is switched off to trigger the next on-time cycle of the switch. Once the secondary current is detected to be greater than a first threshold value, it is determined that the secondary current has been switched on, and until the secondary current is detected to be lower than a second threshold value, it is determined that the secondary current is to be switched off. The hysteresis range of the threshold values prevents error detection of the secondary current.

Abstract: A power metal oxide semiconductor transistor layout is disclosed. The power metal oxide semiconductor transistor layout uses network of conductive lead line as a connection or a network connection to connect source and drain regions thereby achieves advantages of a high uniformity of current, low Rds_on, much less power loss, an actual line density two times larger than that of conventional layouts and a strengthened resistance to electron migration.

Abstract: A driver circuit for a DC light source supplies a voltage generated by a DC-to-DC converter for a plurality of lamp strings connected in parallel and a plurality of driving currents generated by a current mirror for the lamp strings, such that the lamp strings may have well controlled or uniform brightness.

Abstract: A circuit for driving a depletion-type JFET comprises a capacitor connected between the gate of the depletion-type JFET and a control signal, and a switch that is controlled by the control signal connected between the gate and source of the depletion-type JFET. The depletion-type JFET is turned on when the control signal is at a high voltage, and is turned off when the control signal is switched to a low voltage. The circuit and its driven depletion-type JFET can be integrated on a single chip to be a new power switch apparatus.

Abstract: A plurality of switches, an inductor and two capacitors are configured to be a boost-inverting converter. To operate the converter in a boost-inverting mode, a control apparatus and method switch the switches such that the inductor is energized in a first phase, the first capacitor is discharged to produce an inverting voltage in a second phase, and the second capacitor is charged to produce a boost voltage in a third phase. Therefore, the boost-inverting converter has lower peak inductor current and less power loss, and the limitation to the switch design for the boost-inverting converter is relaxed.

Abstract: A dual-input power converter comprises two power stages using a common low-side element, a first input for coupling a first input voltage to the first power stage, a second input for coupling a second input voltage to the second power stage, and a controller for driving the first and second power stages to convert the first or second input voltage to an output voltage.