Nxp B.v.

Nxp USA, Inc.

Bin Shao

Sri Harsh Pakala

A switched capacitor (SC) power stage includes a first stage circuit with a set of switches coupled in series, a first flying capacitor coupled to a first node between a first and second switch and to a second node between a fifth and sixth switch, a second flying capacitor coupled to a third node between the second and a third switch and to a fourth node between a seventh and eighth switch, and a third flying capacitor coupled to a fifth node between a third and fourth switch and a second terminal coupled to the second node. A control circuit establishes a first configuration of the switches to precharge the first, second, and third flying capacitors to a first voltage, and a second configuration of the switches to precharge the first and second flying capacitors to a second voltage while the third flying capacitor remains charged at the first voltage.

Precharge in a switched capacitor (SC) converter

A current monitor includes current sense logic and a processor. The current sense logic senses inductor current at a predetermined time point during operation of a constant on-time regulator. The processor determines output current of the constant on-time regulator based on the inductor current sensed at the predetermined time point. The predetermined time point corresponds to half of an on-time period of the constant on-time regulator. The output current may be determined during continuous conduction mode (CCM) or discontinuous conduction mode (DCM). During DCM mode, the processor determines the output current of the constant on-time regulator based on a skip time.

Measuring current in a constant on-time regulator

Embodiments of switched capacitor voltage converters and methods for operating a switched capacitor voltage converter are disclosed. In an embodiment, a switched capacitor voltage converter includes serially connected switching devices, a voltage generator connected to the serially connected switching devices and configured to generate driver voltages in response to a first voltage at a first terminal that is connected to the serially connected switching devices, and voltage drivers configured to drive the serially connected switching devices based on the driver voltages.

Switched capacitor voltage converter and method for operating a switched capacitor voltage converter

A current limiter circuit for limiting current through a pass device is disclosed. The current limiter circuit includes a accurate/fast current limiter circuit, a coarse/slow current limiter control circuit and a pass device having an input port, an output port and an on/off control port. A control circuit couple to the accurate/fast current limiter circuit and the on/off control port is also included. The accurate/fast current limiter circuit is coupled to the input port and the output port and the coarse/slow current limiter control circuit is coupled to the input port and the output port and an on/off control port of the accurate/fast current limiter circuit.

Current limiter

Embodiments of switched capacitor voltage converters and methods for operating a switched capacitor voltage converter are disclosed. In an embodiment, a switched capacitor voltage converter includes serially connected switching devices, a voltage generator connected to the serially connected switching devices and configured to generate an output voltage for a bootstrap capacitor in response to a first voltage at a first terminal that is connected to the serially connected switching devices, and voltage drivers configured to drive the serially connected switching devices based on the output voltage.

Embodiments of ripple generation devices for a constant on-time voltage regulator and methods for ripple generation for a constant on-time voltage regulator are described. In one embodiment, a ripple generation device for a constant on-time voltage regulator includes a ripple generator configured to generate a ripple signal, a detector operably connected to the ripple generator and configured to detect a difference between an amplitude of the ripple signal and at least one reference amplitude and a feedback controller operably connected to the ripple generator and the detector and configured to generate a control signal for controlling the amplitude of the ripple signal based on the detected difference. Other embodiments are also described.

Ripple generation device and method for a constant on-time voltage regulator

Embodiments of voltage regulators and methods for operating a voltage regulator are described. In one embodiment, a voltage regulator includes a power stage configured to convert an input direct current (DC) voltage into an output DC voltage, a driver device configured to drive the power stage, a timer configured to generate a constant on-time signal, a ripple generation device configured to generate a ripple signal, a comparator configured to perform voltage comparison in response to the ripple signal to generate an input to the timer, and a controller configured to generate a drive signal for the driver device in response to an inductor peak current in the voltage regulator and the constant on-time signal. Other embodiments are also described.

Growing community of inventors

Chandler, AZ, United States of America

Bin Shao