Abstract: A switching regulator circuit includes a power stage and a compensation network. The compensation network includes a programmable transconductance (gm), having a first selectable transconductance such a closed loop transfer function of the switching regulator circuit may be characterized by a first transfer function having a having a first DC open loop gain and a first bandwidth, and by a second transfer function having a second DC open loop gain and a second bandwidth.

Abstract: Embodiments of the present invention include charge pump circuits and methods. In one embodiment, a first charge pump receives a voltage and generates a first charge pump output voltage and current for supplying the power requirements of a circuit. A second charge pump is coupled in series with the first charge pump. The second charge pump generates a second charge pump output voltage and current for supplying different power requirements of the circuit. In one embodiment, the first charge pump provides a high current low voltage output to a first circuit and the second charge pump provides a low current high voltage output to a second circuit. Capacitors of the first charge pump may be external to an integrated circuit and capacitors of the second charge pump may be internal to the integrated circuit.

Abstract: In one embodiment the present invention includes a system and method of charging a battery using a switching regulator. In one embodiment, a switching regulator receives an input voltage and input current. The output of the switching regulator is coupled to a battery to be charged. The switching regulator provides a current into the battery that is larger than the current into the switching regulator. As the voltage on the battery increases, the current provided by the switching regulator is reduced. The present invention may be implemented using either analog or digital techniques for reducing the current into the battery as the battery voltage increases.

Abstract: Embodiments of the present invention include charge pump circuits and methods. In one embodiment, a first charge pump receives a voltage and generates a first charge pump output voltage and current for supplying the power requirements of a circuit. A second charge pump is coupled in series with the first charge pump. The second charge pump generates a second charge pump output voltage and current for supplying different power requirements of the circuit. In one embodiment, the first charge pump provides a high current low voltage output to a first circuit and the second charge pump provides a low current high voltage output to a second circuit. Capacitors of the first charge pump may be external to an integrated circuit and capacitors of the second charge pump may be internal to the integrated circuit.

Abstract: Embodiments of the present invention include circuits and methods for calibrating lens displacement in a voltage controlled actuator. In one embodiment, a calibration circuit comprises a programmable voltage source that provides a voltage to a control terminal of an actuator to set a lens displacement, a switch that selectively decouples said programmable voltage source from said control terminal, a current source that provides a reference current to said control terminal when the control terminal is decoupled from said programmable voltage source, a comparator that senses a voltage difference between said programmable voltage source and said control terminal, and a timer coupled to an output of the comparator. The timer measures a time period required to increase the control terminal voltage. The capacitance of the actuator may be determined and used to calibrate the position of a lens.

Abstract: In one embodiment the present invention includes a system and method of charging a battery using a switching regulator. In one embodiment, a switching regulator receives an input voltage and input current. The output of the switching regulator is coupled to a battery to be charged. The switching regulator provides a current into the battery that is larger than the current into the switching regulator. As the voltage on the battery increases, the current provided by the switching regulator is reduced. The present invention may be implemented using either analog or digital techniques for reducing the current into the battery as the battery voltage increases.

Abstract: Embodiments of the present invention include circuits and methods for sensing resistance. In one embodiment, a current is generated into a node. The node is coupled to a first terminal of a resistor. A second terminal of the resistor is coupled in series with a capacitance and a reference voltage. The current is turned off when a voltage on the node meets a threshold. A second voltage is detected on the node after the current is turned off. A resistance value is determined based on the first voltage on the node and the second voltage on the node. In one embodiment, the resistor is external to an integrated circuit and sensed through a single pin of the integrated circuit. The integrated circuit may include a current source, comparator, and a digital-to-analog converter.

Abstract: Embodiments of the present invention include charge pump circuits and methods. In one embodiment, a first charge pump receives a voltage and generates a first charge pump output voltage and current for supplying the power requirements of a circuit. A second charge pump is coupled in series with the first charge pump. The second charge pump generates a second charge pump output voltage and current for supplying different power requirements of the circuit. In one embodiment, the first charge pump provides a high current low voltage output to a first circuit and the second charge pump provides a low current high voltage output to a second circuit. Capacitors of the first charge pump may be external to an integrated circuit and capacitors of the second charge pump may be internal to the integrated circuit.

Abstract: Embodiments of the present invention include systems and methods of controlling power in battery operated systems. In one embodiment, the present invention includes a switching regulator for boosting voltage on a depleted battery to power up a system. The system may communicate with an external system to increase the current received from the external system. Embodiments of the present invention include circuits for controlling power received from external power sources such as a USB power source. In another embodiment, input-output control techniques are disclosed for controlling the delivery of power to a system or charging a system battery, or both, from an external power source.

Abstract: Embodiments of the present invention include systems and methods of controlling power in battery operated systems. In one embodiment, the present invention includes a switching regulator for boosting voltage on a depleted battery to power up a system. The system may communicate with an external system to increase the current received from the external system. Embodiments of the present invention include circuits for controlling power received from external power sources such as a USB power source. In another embodiment, input-output control techniques are disclosed for controlling the delivery of power to a system or charging a system battery, or both, from an external power source.

Abstract: Embodiments of the present invention include techniques for charging a battery using a regulator. In one embodiment, the present invention includes an electronic circuit comprising a regulator having an input coupled to a power source for receiving a voltage and a current and an output for providing an output current, an input voltage detection circuit coupled to the power source, and an adjustable current limit circuit for controlling the input or output current of the regulator, wherein input voltage detection circuit monitors the voltage from the power source and the adjustable current limit circuit changes the input or output current of the regulator to optimize the power drawn from power source.

Abstract: In one embodiment the present invention includes an over-current protection method. The method comprises generating a switching signal, starting and stopping a timer, sensing a current through a switch, comparing a response time to a reference time, and generating an over-current alarm signal. The switching signal activates one or more switches in a switching regulator. The timer is started in response to the switch being activated and is stopped in response to the sensed current exceeding a threshold. The response time indicates the time period between the starting and the stopping of the timer. The over-current alarm signal is generated if the response time is less than the reference time.

Abstract: In one embodiment the present invention includes a system and method of charging a battery using a switching regulator. In one embodiment, a switching regulator receives an input voltage and input current. The output of the switching regulator is coupled to a battery to be charged. The switching regulator provides a current into the battery that is larger than the current into the switching regulator. As the voltage on the battery increases, the current provided by the switching regulator is reduced. The present invention may be implemented using either analog or digital techniques for reducing the current into the battery as the battery voltage increases.

Abstract: In one embodiment the present invention includes a system and method of charging a battery using a switching regulator. In one embodiment, a switching regulator receives an input voltage and input current. The output of the switching regulator is coupled to a battery to be charged. The switching regulator provides a current into the battery that is larger than the current into the switching regulator. As the voltage on the battery increases, the current provided by the switching regulator is reduced. The present invention may be implemented using either analog or digital techniques for reducing the current into the battery as the battery voltage increases.

Abstract: Embodiments of the present invention include circuits and methods for calibrating lens displacement in a voltage controlled actuator. In one embodiment, a calibration circuit comprises a programmable voltage source that provides a voltage to a control terminal of an actuator to set a lens displacement, a switch that selectively decouples said programmable voltage source from said control terminal, a current source that provides a reference current to said control terminal when the control terminal is decoupled from said programmable voltage source, a comparator that senses a voltage difference between said programmable voltage source and said control terminal, and a timer coupled to an output of the comparator. The timer measures a time period required to increase the control terminal voltage. The capacitance of the actuator may be determined and used to calibrate the position of a lens.

Abstract: Embodiments of the present invention include techniques for charging a battery. In one embodiment, the present invention includes a method comprising determining if a maximum current output of a power source is above a threshold, configuring a regulator coupled to the power source, wherein the regulator is configured in a pass mode if the maximum current output is above the threshold, and wherein the regulator is configured in a regulation mode if the maximum current output is below the threshold, and generating pulses to a battery, wherein an output of the regulator is coupled to the battery when a pulse is being generated, and the output of the regulator is decoupled from the battery when a pulse is not being generated. In other embodiments, the techniques may be embodied in a circuit including a detection circuit and a switching regulator coupled to a battery through a pulse circuit.

Abstract: In one embodiment the present invention includes an over-current protection method. The method comprises generating a switching signal, starting and stopping a timer, sensing a current through a switch, comparing a response time to a reference time, and generating an over-current alarm signal. The switching signal activates one or more switches in a switching regulator. The timer is started in response to the switch being activated and is stopped in response to the sensed current exceeding a threshold. The response time indicates the time period between the starting and the stopping of the timer. The over-current alarm signal is generated if the response time is less than the reference time.

Abstract: Embodiments of the present invention include techniques for charging a battery using a switching regulator. Some embodiments include programmable switching battery chargers that can be configured using digital techniques. Other embodiments include switching battery chargers that modify the battery current based on sensed circuit conditions such as battery voltage or input current to the switching regulator. In one embodiment, the present invention includes a USB battery charger.

Abstract: A control loop system is provided that employs an active DC output control circuit that more accurately calibrates the desired voltage at a load, e.g. 3.3 volts, by adjusting a trim pin on a DC/DC converter.

Abstract: Embodiments of the present invention include an electronic circuit for performing current sensing. In one embodiment, the present invention includes a first switching transistor and a second switching transistor both coupled to receive a first switching current and a switching signal, and one or more transistors coupled in a first series. A first terminal of an initial transistor in the first series is coupled to a second terminal of the second switching transistor. A second terminal of a last transistor in the first series is coupled to a reference voltage. The first switching current is coupled to a second node between the second terminal of the second switching transistor and the first terminal of the initial transistor in the first series. In this manner, the circuit produces a switching voltage corresponding to said first switching current.