Abstract: The present invention discloses a step up circuit with output floating for driving a load such as a LED or a series of LEDs in a string. The step up circuit comprises an input port, an output port, an inductor, an input capacitor, an output capacitor, a first switch, a second switch and a third switch. The third switch S3 is an additional switch for purpose of high dimming ratio control, short circuit protection and input disconnection realization. Further, the third switch can implement an additional LDO function when the voltage at the input port is larger than the voltage across the load.

Abstract: Embodiments of circuits and methods for a switching mode power supply are described in detail herein. In one embodiment, a switching mode power supply includes a transformer having a primary winding and a secondary winding to supply power to a load, a feedback circuit that generates a feedback signal that varies in relation to the load on the secondary winding, a switching circuit coupled to the primary winding to control current flow through the primary winding, and a control circuit coupled to the switching circuit to control the on/off status of switching circuit in response to the feedback signal and the current flow through the primary winding. The control circuit comprises a spectrum shaping circuit configured to generate a spectrum shaping signal in response to the feedback signal. The spectrum shaping signal can then be used to regulate the switching frequency and the spectrum shaping range.

Abstract: A zero-crossing gain control system is disclosed herein. The system comprises a gain control unit for amplifying an input signal to an output signal, a zero-crossing monitoring circuit for monitoring the input signal or output signal, and a register for latching the digital control signal and generating a gain control signal that controls the gain control unit. The system may further comprise a maximum write time setting circuit for generating a write signal. The digital control signal is written into the register when a zero-crossing state is monitored or a maximum write time since a change occurred on of the digital control signal is expired. An automatic gain control system is also disclosed herein and further comprises a peak detecting circuit for detecting the level of output signal, a logic circuit for lowering or restoring the digital control signal according to the result from the peak detecting circuit.

Abstract: The present disclosure discloses a low drop-out voltage regulator and an electronic device comprising the same. The present disclosure also discloses a method for converting a power supply voltage to a regulated output voltage. The low drop-out voltage regulator comprises a pass device controllable to convert a power supply voltage to a regulated output voltage; and a controller configured to receive an input signal and to provide a driving signal to the control terminal of the pass device based on the input signal, wherein when the input signal is within a predetermined range, the driving signal turns the pass device ON, and the power supply voltage charges the output voltage; and wherein when the input signal is without the predetermined range, the driving signal turns the pass device OFF, and the power supply voltage stops charging the output voltage.

Abstract: The present disclosure discloses a switching mode power supply with constant peak current mode control. During the operation of the switching mode power supply, in one hand, the current flowing through a high-side switch is sensed and compared to a current reference signal to control the turning off of the high-side switch; in the other hand, the output voltage is sensed and compared to a voltage reference signal to control the turning on of the high-side switch. In addition, the current reference signal may be adjusted to a lower value when the switching mode power supply enters light load condition. By using the above control method, the system performance is highly increased.

Abstract: A switching mode power supply with a multi-mode controller is provided. The switching mode power supply may include a transformer having a primary winding and a secondary winding to supply power to a load. A feedback circuit may be included to generate a feedback signal that varies in relation to the load on the secondary winding. The multi-mode controller may include a switching circuit, a frequency control circuit and a current limiting circuit. The switching circuit may be coupled to the primary winding to control current flow through the primary winding. The frequency control circuit may control a switching frequency of the switching circuit based on the feedback signal. The current limiting circuit may limit current flow through the primary winding by causing the switching circuit to suspend current flow through the primary winding when the current reaches a peak current limit that is set based on the feedback signal.

Abstract: An integrated circuit for implementing a switch-mode power converter is disclosed. The integrated circuit comprises at least a first semiconductor die having an electrically quiet surface, a second semiconductor die for controlling the operation of said first semiconductor die stacked on said first semiconductor die having said electrically quiet surface and a lead frame structure for supporting said first semiconductor die and electrically coupling said first and second semiconductor dies to external circuitry.

Abstract: An audio amplifier and a method of operating such an amplifier are disclosed. The audio amplifier includes a switch disabling controller and/or an output set-point controller. The switch disabling controller is configured to disable switching of an output switch circuit or other switch circuit while an input signal represents at least relative silence. The output set-point controller is configured to bring and/or hold first and second switch nodes toward and/or at a set-point voltage while the input signal represents at least relative silence.

Abstract: Apparatus, systems, and methods related to controlling multiple strings of light emitting diodes (LEDs) are disclosed. An apparatus may include internal current limiter circuits that are each coupled in series with an associated string of LEDs and are configured to at least partially regulate the current through the associated string of LEDs. The apparatus may also be configured to control external current limiter circuits that are each coupled in series with a corresponding internal current limiter circuit and the string of LEDs associated with the corresponding internal current limiter circuit.

Abstract: The present disclosure discloses a power converter providing a low output voltage from an offline AC. The power converter defines a voltage window for the input AC signal. Inside the voltage window, the rectified DC waveform is passed through to the output and the storage capacitor; outside the voltage window, the power converter is idle (or the output is blocked from input) and let the output storage capacitor alone supply the load.

Abstract: The present invention provides an adaptive constant on-time switching regulator which comprises a switching circuit, a control circuit, and an output circuit. The control circuit controls the switches in the switching circuit to be turned on for an adaptive constant time, and be turned off for a minimum time.

Abstract: The present invention discloses a light load control circuit and the method accordingly where the synchronous rectification is latched off selectively according to the gate voltage of the synchronous rectifier.

Abstract: A multi-phase voltage regulator is disclosed where each phase is comprised of an array of high and low side transistors that are integrated onto a single substrate. Further, a system of mounting the voltage regulator onto a flip chip and lead frame is disclosed wherein the source and drain lines form an interdigital pattern.

Abstract: The present invention discloses an adaptive voltage position DC-DC regulator and the method thereof, the regulator comprising a main circuit and a control circuit which includes a sensing unit, a feedback unit, a comparing unit, a PWM generator and a driver. The regulator realizes the adaptive voltage position control with simple internal circuit and fewer pins.

Abstract: Switching mode power supplies and associated methods of control are disclosed herein. In one embodiment, a method for controlling a switching mode power supply includes determining whether the switching mode power supply is in a burst mode. If the switching mode power supply is in the burst mode, the method includes recording a switching time with and without switching pulses to obtain a current value of an equivalent frequency and generating a peak current limit that decreases as a load becomes lighter based on the equivalent frequency, thereby maintaining the equivalent frequency at the current value above an audible range. If the switching mode power supply is not in the burst mode, the method includes continuing to monitor whether the switching mode power supply is in the burst mode.

Abstract: The present invention provides a smoke-free ESD protection structure used in integrated circuit devices. A JFET or n-channel MOS transistor is coupled between an I/O pad, and a transistor and diode, wherein the JFET or n-channel MOS transistor limits the current flowing through the diode and transistor to prevent the integrated circuit device from heating up and catching on fire or smoke during the smoke test. Moreover, the integrated circuit device will not be damaged by the smoke test.

Abstract: A circuit for controlling the switch frequency of an inverter that strikes and drives fluorescent lamps is disclosed. The circuit comprises a frequency generator and an offset circuit. The offset circuit provides a current signal in response to the lamp status. The frequency generator provides a frequency control signal in respond to the current signal so as to control the switch frequency of the inverter. When the lamp is open, the switch frequency of the inverter is higher; when the lamp is lighted, the switch frequency of the inverter is lower.

Abstract: Methods and circuits for CCFL driving circuit control are disclosed according to various embodiments of the present disclosure. In certain embodiments, the methods and circuits for CCFL driving circuit control provide a control signal for regulating both the duty ratio and frequency of the switching control signal that controls the CCFL driving circuit. External components for control loop compensation and frequency sweeping rate, and/or striking frequency setting may also be utilized.

Abstract: The embodiments of the present invention disclose a semiconductor device and a method for forming the semiconductor device. Wherein the semiconductor comprises: a first semiconductor layer, having a first conductivity type on a semiconductor substrate, a guard ring region, formed in the surface of the first semiconductor layer, having a second conductivity type; a Schottky diode metal contact, coupled to the first semiconductor layer, wherein the guard ring region is at periphery of the Schottky diode interface, and wherein the Schottky diode metal contact has no direct electrical connection with the guard ring region; and an electrical resistance module, coupled between the Schottky diode metal contact and the guard ring. Due to the ballasting effect from the electrical resistance module, the minority injection or the parasitic transistor action are alleviated. Thus, forward current capability is extended without introducing significant minority injection.

Abstract: A method of driving a lamp that uses a DC to AC inverter that is connected to a primary winding of a transformer is disclosed. The inverter frequency is variable, and in one embodiment, may be controlled by a voltage controlled oscillator. Circuitry is included that monitors the phase relationship between a voltage across a secondary of the transformer and a current through the primary of the transformer. The circuitry monitors the phase relationship and adjusts the inverter frequency, such as by adjusting voltage controlled oscillator, so that the phase relationship is maintained at a predetermined relationship.