Psemi Corporation

Peregrine Semiconductor Corporation

Arctic Sand Technologies, Inc.

Murata Manufacturing Co., Ltd.

Artic Sand Technologies, Inc.

Aichen Low

Gregory Szczeszynski

David M Giuliano

Oscar Blyde

Jeff Summit

Walid Fouad Mohamed Aboueldahab

Brian Zanchi

Chak Sang Ngai

David Guiliano

Walid Aboueldahab

Circuit embodiments for a switched-capacitor power converter, and/or methods of operation of such a converter, that robustly deal with various startup scenarios, are efficient and low cost, and have quick startup times to steady-state converter operation. Embodiments prevent full charge pump capacitor discharge during shutdown of a converter and/or rebalance charge pump capacitors during a startup period before switching operation by discharging and/or precharging the charge pump capacitors. Embodiments may include a dedicated rebalancer circuit that includes a voltage sensing circuit coupled to an output voltage of a converter, and a balance circuit configured to charge or discharge each charge pump capacitor towards a target steady-state multiple of the output voltage of the converter as a function of an output signal from the voltage sensing circuit indicative of the output voltage. Embodiments prevent or limit current in-rush to a converter during a startup state.

Startup of switched capacitor step-down power converter

Circuits/methods for controlling the startup of multiple parallel power converters that avoid inrush current or switch overstress in an added power converter or a power converter having fault conditions. Embodiments include node status detectors coupled to nodes within parallel-connected power converters to monitor voltage/current and configured in some embodiments to work in parallel with an output status detector measuring the startup output voltage of a power converter. With charge pump-based power converters, the node status detectors ensure that the power converter pump capacitors are charged while the output capacitor is charged as well. For such embodiments, a soft-start period of startup may be considered finished if both the shared output capacitors and the power converter pump capacitors are charged to target values. Embodiments may also be used for fault detection during steady-state operation.

Startup detection for parallel power converters

In a power converter having a regulator and charge pump, both of which operate in plural modes, a controller receives information indicative of the power converter's operation and, based at least in part on said information, causes transitions between regulator modes and transitions between charge-pump modes.

Adaptive control for reconfiguring a regulator and/or a charge pump for a power converter

An apparatus for converting a first voltage into a second voltage includes a reconfigurable switched capacitor power converter having a selectable conversion gain. The power converter has switch elements configured to electrically interconnect capacitors to one another and/or to the first or second voltage in successive states. The switch elements are configured to interconnect at least some capacitors to one another through the switch elements. A controller causes the reconfigurable switched capacitor power converter to transition between first and second operation modes. The controller minimizes electrical transients arising from transition between modes. In the first operating mode, the power converter operates with a first conversion gain. In the second operating mode, it operates with a second conversion gain.

Charge adjustment techniques for switched capacitor power converter

Transient or fault conditions for a switched capacitor power converter are detected by measuring one or more of internal voltages and/or currents associated with switching elements (e.g., transistors) or phase nodes, or voltages or currents at terminals of the converter, and based on these measurements detect that a condition has occurred when the measurements deviate from a predetermined range. Upon detection of the condition fault control circuitry alters operation of the converter, for example, by using a high voltage switch to electrically disconnect at least some of the switching elements from one or more terminals of the converter, or by altering timing characteristics of the phase signals.

Protection of switched capacitor power converter

An apparatus for power conversion includes a switching network that controls interconnections between pump capacitors in a capacitor network that has a terminal coupled to a current source, and a charge-management subsystem. In operation, the switching network causes the capacitor network to execute charge-pump operating cycles during each of which the capacitor network adopts different configurations in response to different configurations of the switching network. At the start of a first charge-pump operating cycle, each pump capacitor assumes a corresponding initial state. The charge-management subsystem restores each pump capacitor to the initial state by the start of a second charge-pump operating cycle that follows the first charge-pump operating cycle.

Charge pump stability control

Circuits and methods for reducing lagging responses of a power converter to changes in circuit voltages or current, over-shoot/under-shoot when a target output voltage changes faster than the power converter's response, and open loop conditions. Embodiments include scanning a feedback voltage from a load powered by a voltage output by a power converter controlled by a PWM control signal; detecting an under-regulation condition; and, while the under-regulation condition is detected, increasing a clock signal rate to a counter outputting a count value usable to generate the PWM control signal. Embodiments include comparing a target output voltage to a signal representative of an output voltage of the power converter; indicating an under-shoot or over-shoot condition if the voltage difference exceeds a corresponding offset value; and limiting the range of values for an M-bit count value used to generate the PWM control signal to mitigate the under-shoot or over-shoot condition.

Controller for a power converter

A step-up power-converter has stack nodes, each of which connects to a stack switch and to a pump capacitor to form a switched-capacitor network. Among the stack nodes are first and second stack-nodes. The second stack-node drives a particular stack switch from the plurality of stack switches. When all of the stack switches are open, the first voltage causes the first stack-node to have a first stack-node voltage and causes the second stack-node to have a second stack-node voltage that is less than the first stack-node voltage. During the first state, the second stack-node voltage is insufficient to drive the particular stack-switch. During the second state, the second stack-node voltage is sufficient to drive the particular stack-switch. Causing the switched-capacitor network to transition from the first state to the second state includes, among other things, causing the second stack-node voltage to become sufficient to drive the particular stack-switch.

Start-up of step-up power converter with switched-capacitor network

Circuits and methods encompassing a power converter that can be started and operated in a reversed unidirectional manner or in a bidirectional manner while providing sufficient voltage for an associated auxiliary circuit and start-up without added external circuitry for a voltage booster and/or a pre-charge circuit—that is, with zero external components or a reduced number of external components. Embodiments include an auxiliary circuit configured to selectively couple the greater of a first or a second voltage from a power converter to provide power to the auxiliary circuit. Embodiments include an auxiliary circuit configured to select a subcircuit coupled to the greater of a first or a second voltage from a power converter to provide an output for the auxiliary circuit. Embodiments include a charge pump including a gate driver configured to be selectively coupled to one of a first voltage node or second voltage node of the charge pump.

Power converters with integrated bidirectional startup

Circuits/methods for controlling the startup of multiple parallel power converters that avoid inrush current or switch overstress in an added power converter or a power converter having fault conditions. Embodiments include node status detectors coupled to nodes within parallel-connected power converters to monitor voltage/current and configured in some embodiments to work in parallel with an output status detector measuring the startup output voltage of a power converter. With charge pump-based power converters, the node status detectors ensure that the power converter pump capacitors are charged while the output capacitor is charged as well. For such embodiments, a softstart period of startup may be considered finished if both the shared output capacitors and the power converter pump capacitors are charged to target values. Embodiments may also be used for fault detection during steady-state operation.

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Cambridge, MA, United States of America

Aichen Low