Intersil Americas Inc.

Xuelin Wu

Congzhong Huang

Sicheng Chen

Xiping Yang

Michael M Walters

Shea Lynn Petricek

Sisan Shen

Jian-Song Chen

A multi-channel LED driver includes a plurality of linear current regulators, each connected to a bottom of a string of series connected LEDs of a multi-channel LED that controls a bias current and the string of series connected LEDs responsive to an LED bias reference voltage. A dynamic headroom regulation voltage control circuit monitors the headroom regulation voltage at the bottom of each string of the series connected LEDs in the multi-channel LED and generates a reference voltage controlling each of the headroom regulation voltages responsive to the LED bias reference voltage.

LED driver with adaptive dynamic headroom voltage control

A multi-phase non-inverting buck boost voltage converter has a plurality of buck boost voltage regulators. Each regulator is associated with a separate phase for generating a regulated output voltage responsive to an input voltage. A plurality of current sensors are each associated with one of the plurality of buck boost voltage regulators for monitoring an input current to the associated buck boost voltage regulator and generating a current sense signal for the associated phase. A plurality of buck boost mode control circuitries are each associated with one of the buck boost regulator for controlling an associated buck boost voltage regulator using peak current mode control in a buck mode of operation and valley current mode control in boost mode of operation responsive to a common error voltage and the associated current sense signal. The plurality of buck boost mode control circuitries provides current balancing between the phases. A voltage error circuit generates the error voltage responsive to the regulated output voltage.

Multi-phase non-inverting buck boost voltage converter

A synthetic ripple regulator including frequency control based on a reference clock. The regulator includes an error network, a ripple detector, a combiner, a ripple generator, a comparator network and a phase comparator. The error network provides an error signal indicative of relative error of the output voltage. The ripple detector provides a ramp control signal based on the input and output voltages and a pulse control signal. The combiner adjusts the ramp control signal based on a frequency compensation signal to provide an adjusted ramp control signal. The ripple generator develops a ripple control signal based on the adjusted ramp control signal. The comparator network develops the pulse control signal to control switching based on the error signal and the ripple control signal. The phase comparator compares the pulse control signal with the reference clock and provides the frequency compensation signal.

Synthetic ripple regulator with frequency control

A DC-DC voltage converter has a pair of switching transistors to provide an output voltage and are alternately switched in a boost mode of operation responsive to control signals. An inductor is connected to the pair of switching transistor and has an inductor current flowing there through. A current sensor monitors an input current and generates a current sense signal responsive thereto. Control circuitry generates the control signals to the second pair of switching transistors responsive to the current sense signal, the output voltage and a current limit signal, wherein when the current limit signal indicates the inductor current exceeds a current limit the control signals configure the pair of switching transistors to decrease the inductor current.

System and method for current limiting a DC-DC converter

A buck boost converter generates a regulated output voltage responsive to an input voltage and switching control signals. Switching control circuitry generates the switching control signals responsive to the regulated output voltage, a maximum duty cycle signal and a mode signal. Mode control circuitry generates the maximum duty cycle signal and the mode signal responsive to a buck PWM signal and a boost PWM signal, a first clock signal and a second clock signal phase shifted from the first clock signal by a fixed, programmable amount. A phase shifter generates the first clock signal and the second clock signal responsive to a reference voltage and a synchronization signal.

Clock phase shifter for use with buck-boost converter

A multi-phase voltage regulator comprises a plurality of DC/DC voltage regulators. Each of the DC/DC voltage regulators is associated with a particular phase of the multi-phase regulator. Each of the regulators comprises a first switching transistor connected between an input voltage node and a phase node responsive to switching control signals. A second switching transistor is connected between the phase node and a ground node and is responsive to the switching control signals. An inductor is connected between the phase node and an output voltage node. Control logic generates the switching control signals responsive to a pulse control signal. PFM/PWM transition logic generates the pulse control signal. The pulse control signal transitions between a PWM signal and a PFM signal responsive to an error voltage, a feedback voltage from the output voltage node and an inductor current through the inductor. An error amplifier generates the error voltage responsive to the feedback voltage and a reference voltage. The output of each error amplifier in each of the plurality of phases are connected to each other. A capacitor is connected between the output voltage node and a ground node.

System and method for PFM/PWM mode transition within a multi-phase buck converter

A non-inverting buck boost voltage converter includes a buck boost voltage regulation circuitry for generating a regulated output voltage responsive to an input voltage. A current sensor monitors an input current to the buck boost voltage regulation circuitry. Buck boost mode control circuitry controls the buck boost voltage regulation circuitry using peak current mode control in a buck mode of operation and valley current mode control in boost mode of operation responsive to the monitored input current.

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Plano, TX, United States of America

Xuelin Wu