Allegro Microsystems, LLC

Allergo Microsystems, LLC

Bassem Alnahas

Gregory Szczeszynski

Vijay Mangtani

Pranav Raval

Nai-Chi Lee

Richard Garvey

Xiaowu Sun

A controller for a Buck-Boost converter includes a feedback control circuit responsive to the converter output and configured to generate a control signal for the Buck switch and a feed forward control circuit responsive to the input voltage and configured to generate a control signal for the Boost switch. The feed forward circuit is decoupled from the converter output and may be programmable to select a predetermined output voltage.

Buck-boost converter control circuits and techniques

An LED driver circuit selects a regulated voltage value for use in driving one or more LEDs based on dimming duty cycle. In some embodiments, the regulated voltage value may be selected in accordance with a function that decreases monotonically with increasing dimming duty cycle. In this manner, LED current accuracy can be achieved at lower dimming duty cycles, while still achieving enhanced operational efficiency at higher dimming duty cycles.

Driver circuit using dynamic regulation and related techniques

A buck-boost switching regulator has an output voltage boost circuit to provide a boosted output voltage. The boosted voltage is used to generate higher voltage control signals to gates of NMOS switches, resulting in an ability to operate at lower input voltages.

Switching regulator circuit allowing a lower input voltage

An apparatus and method for measuring battery voltage includes a first capacitor configured to receive a charge from a battery. A first switch may be configured to selectively couple the first capacitor to the battery. A second capacitor may be coupled to a reference potential. A second switch may be configured to selectively couple the second capacitor to the first capacitor to transfer at least a portion of the charge on the first capacitor to the second capacitor.

System and method for measuring battery voltage

Electronic circuits provide an error signal to control a regulated output voltage signal generated by a controllable DC-DC converter for driving one or more series connected strings of light emitting diodes.

Electronic circuits for driving series connected light emitting diode strings

Control circuits and techniques are provided for use with DC-DC converters. The circuits and techniques may, in some implementations, be used with LED driver systems. In some embodiments control circuits are provided that rely on multiple different feedback paths to adjust a duty cycle of a DC-DC converter. In some embodiments, control circuits are provided that switch between multiple capacitors to provide as duty cycle control signal for use with a DC-DC converter.

Method and apparatus to control a DC-DC converter

A control circuit used to control a DC-DC converter includes a duty cycle control unit to control a duty cycle of the DC-DC converter and a hysteretic control unit to maintain a voltage at an output of the DC-DC converter within a narrow range during certain operational time periods. The hysteretic control unit may maintain the converter output voltage within the range by alternately enabling and disabling the duty cycle control unit based on feedback from the DC-DC converter output. In at least one embodiment, the control circuit is used within LED driver circuitry for driving a plurality of LED channels.

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Manchester, NH, United States of America

Bassem Alnahas