National Semiconductor Corporation

Advanced Analogic Technologies Incorporated

Skyworks Solutions, Inc.

Skyworks Soluteqns, Enc.

George Adrian Hariman

Richard Kent Williams

Kevin Peter D'Angelo

David Alan Brown

Wendy Ng

Kenji Tomiyoshi

Chak Sang Ngai

Faruk Jose Nome Silva

Faruk J Nome

Daniel Chang

Roger Allen Smullen

Boost regulators with dynamic regulation band are disclosed. In certain configurations, a boost regulator system includes a field effect transistor (FET) current source having a gate controlled by a current level control signal, a source that receives a regulator output voltage, and a drain that outputs a current. The boost regulator system further includes a boost regulator that generates the regulator output voltage based on a reference voltage. The boost regulator includes a headroom detection circuit electrically coupled to the drain of the FET current source and operable to generate a headroom signal indicating a detected voltage headroom of the FET current source. The boost regulator further includes a regulator control circuit that controls a voltage level of the reference voltage based on the headroom signal, and that controls a size of a regulation band of the boost regulator based on the current level control signal.

Boost regulators with dynamic regulation band

Apparatus and methods for boost regulators with dynamic regulation band are disclosed. In certain configurations, a boost regulator system includes a boost regulator, a current source, and a light emitting element, such as a flash LED, that is controlled using a current generated by the current source. The boost regulator generates an output voltage that is used to power the current source. The boost regulator operates with a regulation band that changes based on a current level of the light emitting element.

A voltage regulator device is disclosed, comprising a first pin and a second pin, a regulator circuit implemented between the first pin and the second pin, one or more internal blocks configured to be powered through a supply node to facilitate operation of the regulator circuit and an internal supply circuit coupled to the first pin, the second pin, and the supply node, the internal supply circuit configured to provide a supply voltage to the supply node from either or both of the first and second pins.

Circuits, devices and methods related to internal supply for voltage regulators

Apparatus and methods for boost regulators with dynamic regulation band

A distributed system for driving strings of series-connected LEDs for backlighting, display and lighting applications that includes multiple intelligent satellite LED driver ICs connected to an interface IC via a serial lighting interface bus. The interface IC translates information obtained from a host microcontroller into instructions for the satellite LED driver ICs pertaining to such parameters as duty factor, current levels, phase delay and fault settings. Fault conditions in the LED driver ICs can be transmitted back to the interface IC. An analog current sense feedback system which also links the LED driver ICs determines the supply voltage for the LED strings.

Low cost LED driver with integral dimming capability

Various implementations include circuits, devices and/or methods that enable the repeated generation of controlled surges with lower risk of component failure. Some implementations include a discharge control assembly including a discharge circuit and a controller. In some implementations, the discharge circuit is selectively connectable to a driver circuit, and the discharge circuit is configured to provide a dominant discharge path for the driver circuit when the driver circuit is effectively decoupled from a first load in order to decay an electrical condition of the driver circuit produced prior to the driver circuit being effectively decoupled from the first load. In some implementations, the controller is configured to selectively connect the driver circuit to a combination of the discharge circuit and the first load, and in at least one combination the discharge circuit is effectively coupled to the driver circuit when the first load is effectively decoupled from the driver circuit.

Flash-LED driver discharge control

A distributed system for driving strings of series-connected LEDs for backlighting, display and lighting applications includes multiple intelligent satellite LED driver ICs connected to a an interface IC via serial bus. The interface IC translates information obtained from a host microcontroller into instructions for the satellite LED driver ICs pertaining to such parameters as duty factor, current levels, phase delay and fault settings. Fault conditions in the LED driver ICs can be transmitted back to the interface IC. An analog current sense feedback system which also links the LED driver ICs determines the supply voltage for the LED strings.

A distributed system for driving strings of series-connected LEDs for backlighting, display and lighting applications includes multiple intelligent satellite LED driver ICs connected to a an interface IC via serial bus. The interface IC translates information obtained from a host microcontroller into instructions for the satellite LED driver ICs pertaining to such parameters as duty factor, current levels, phase delay and fault settings. Fault conditions in the LED driver ICs can be transmitted back to, the interface IC. An analog current sense feedback system which also links the LED driver ICs determines the supply voltage for the LED strings.

A synchronous buck regulator controller is provided. The regulator controller includes switch control circuitry, an unloading event detection circuit, an inductor current detection circuit, and a synchronous switch control logic circuit. In operation, the regulator controller controls a main switch and a synchronous switch to control the buck regulation. The unloading event detection circuit is arranged to detect an unloading event, and to assert an unloading event signal if such an event is detected. The inductor current detection circuit is arranged to assert an inductor current detection signal if the inductor current is close to zero. The synchronous switch control logic circuit is arranged to block the synchronous switch from turning on if the unloading event signal is asserted and the inductor current detection signal is not asserted. However, if the inductor current detection signal is subsequently asserted while the unloading event signal is still asserted, the synchronous switch control logic circuit stops blocking the synchronous switch from turning on.

Apparatus and method for faster unloading of transient response in a synchronous buck switching regulator

A synchronous switching voltage regulator circuit is provided. After the first PWM pulse or at the end of a soft-start, a gradual transition is made from asynchronous rectification to fully synchronous rectification, or vice versa. During the gradual transition, the error voltage is level-shifted down to correct for error caused by reverse current through the body diode of the main switch.

Apparatus and method for reverse current correction for a switching regulator

A current difference circuit is provided. The currents difference circuit provides an output current that is the difference of two input currents, while employing feedforward to clamp the output current. The current difference circuit brings the lower of the two input currents along with the higher of the two such that the difference between them is always constant if the difference is beyond the clamp range.

Current differencing circuit with feedforward clamp

A feed-forward path is combined with a feed-back path to produce an output signal representation of an input signal frequency. The feed-forward path adjusts the output signal representation in response to a change in the input signal frequency, and does so in a response time that is independent of the feed-back path. Input frequencies can be represented as voltages, and first and second input frequency ranges which differ from one another can both be represented in the same range of voltages.

Producing a frequency-representative signal with rapid adjustment to frequency changes

Method and circuit for automatic correction of emulated inductor current without knowledge of actual inductor current ramp for an emulated current mode (ECM) PWM switching regulator. In an ECM-PWM switching regulator a compensation ramp component is usually added to an up-slope. An excess ramp component may also be added compared to actual inductor current. According to one embodiment of the present invention, an integrating negative feedback circuit is employed to reduce both extra components. According to another embodiment, a single integrating negative feedback loop is added to the ECM-PWM regulator to retain the compensation ramp component while reducing the excess ramp component. According to a further embodiment, excess ramp component is reduced by adding the integrating negative feedback loop at an end stage of the circuit. Finally, the feedback loop with two duplicate track-and-hold circuitry may be added to reduce the excess ramp component, while retaining the compensation component.

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Sunnyvale, CA, United States of America

George Adrian Hariman