A voltage regulator circuit may include a first loop that forms a reference signal that substantially does not vary in response to the output voltage, the reference circuit may also be configured to form a control signal that is representative of changes in the reference signal. The voltage regulator circuit may also include a second loop configured to form a value of a control electrode of an output transistor according to the control signal and wherein the output circuit is configured to change a value of the control electrode according to a difference between the output voltage and the reference signal.

A voltage regulator circuit may include a first loop that forms a reference signal that substantially does not vary in response to the output voltage, the reference circuit may also be configured to form a control signal that is representative of changes in the reference signal. The voltage regulator circuit may also include a second loop configured to form a value of a control electrode of an output transistor according to the control signal and wherein the output circuit is configured to change a value of the control electrode according to a difference between the output voltage and the reference signal.

An actuator in a HVAC system includes a housing having an interior-facing surface and an exterior-facing surface. The actuator includes magnetic field sensor(s) located within the housing and arranged adjacent to the interior-facing surface. The actuator includes a user input device retaining magnet(s) that are movable into multiple different positions along the exterior-facing surface of the housing. An actuator controller includes a magnet locator that determines a location of the magnet(s) with respect to the magnetic field sensor(s) based on data generated by the magnetic field sensor(s). The actuator controller also includes a settings generator that generates settings for the actuator based on the location of the magnet(s) determined via the magnet locator.

An actuator in a HVAC system includes a housing having an interior-facing surface and an exterior-facing surface. The actuator includes magnetic field sensor(s) located within the housing and arranged adjacent to the interior-facing surface. The actuator includes a user input device retaining magnet(s) that are movable into multiple different positions along the exterior-facing surface of the housing. An actuator controller includes a magnet locator that determines a location of the magnet(s) with respect to the magnetic field sensor(s) based on data generated by the magnetic field sensor(s). The actuator controller also includes a settings generator that generates settings for the actuator based on the location of the magnet(s) determined via the magnet locator.

Systems, methods and apparatuses for efficient control of a pass device driven into its triode region of operation are described. Output drive capability of an operational amplifier driving the pass device is boosted during a transition of the pass device from operating in a triode region to operating in a saturation region. An exemplary implementation of an LDO controlling pass devices for providing burst RF power to a power amplifier is described. An alternative configuration that boosts the driving capability of the operational amplifier using an asymmetrical mirroring circuit is also described.