Abstract: One embodiment of a display backlight driver integrated circuit can be configured for operation in at least two different ways. A first method transfers data from an EEPROM to hardware registers prior to regular operation. A second method also transfers data from an EEPROM to registers. However, hardware registers can be overwritten with data accepted from a control bus, prior to regular operation. A keyboard driver IC can detect the presence or absence of a cable to an LED. If the cable is absent, the driver IC will not supply power for the LED. One embodiment of a keyboard and display backlight control system can be configured to allow substantially independent operation.

Abstract: One embodiment of a display backlight driver integrated circuit can be configured for operation in at least two different ways. A first method transfers data from an EEPROM to hardware registers prior to regular operation. A second method also transfers data from an EEPROM to registers. However, hardware registers can be overwritten with data accepted from a control bus, prior to regular operation. A keyboard driver IC can detect the presence or absence of a cable to an LED. If the cable is absent, the driver IC will not supply power for the LED. One embodiment of a keyboard and display backlight control system can be configured to allow substantially independent operation.

Abstract: A switched-mode power supply with reduced electromagnetic interference (EMI) is described. This switched-mode power supply includes a modulation circuit that continuously frequency modulates a control signal over a bandwidth associated with a spread-spectrum modulation signal. By frequency modulating the control signal in the switched-mode power supply, spectral content associated with a modulated switching signal is spread evenly over the bandwidth, thereby reducing the EMI.

Abstract: A system and method are described for charging a battery in a portable electronic device wherein the battery is charged using a constant-current, constant-voltage charging process. In described embodiments, a resistance is received for a current loop that includes a charger and the battery. Then, during a constant-current charging phase, a constant current is output from the charger until an output voltage of the charger reaches a target voltage. The target voltage includes a battery target voltage and a compensation voltage based on the received resistance and a charging current. When the output voltage of the charger reaches the target voltage, the charger switches from the constant-current phase to a constant-voltage phase. Then during the constant-voltage phase, the charger outputs the target voltage until the charging current drops below a minimum value at which time the charging process is complete.

Abstract: The disclosed embodiments relate to a power supply for a portable electronic device. The power supply includes a power source and a nonlinear inductor. The nonlinear inductor includes a first core and a second core connected in series to the first core, wherein the second core has a higher permeability than the first core.

Abstract: The disclosed embodiments provide a power management system that supplies power to components in an electronic device. The power management system includes a system microcontroller (SMC) and a charger. During operation, the power management system accepts power from at least one of a power adapter and a solar panel. Next, the power management system supplies the power to components in the electronic device without using a converter circuit between the solar panel and the power management system.

Abstract: One embodiment of a display backlight driver integrated circuit can be configured for operation in at least two different ways. A first method transfers data from an EEPROM to hardware registers prior to regular operation. A second method also transfers data from an EEPROM to registers. However, hardware registers can be overwritten with data accepted from a control bus, prior to regular operation. A keyboard driver IC can detect the presence or absence of a cable to an LED. If the cable is absent, the driver IC will not supply power for the LED. One embodiment of a keyboard and display backlight control system can be configured to allow substantially independent operation.

Abstract: One embodiment of a display backlight driver integrated circuit can be configured for operation in at least two different ways. A first method transfers data from an EEPROM to hardware registers prior to regular operation. A second method also transfers data from an EEPROM to registers. However, hardware registers can be overwritten with data accepted from a control bus, prior to regular operation. A keyboard driver IC can detect the presence or absence of a cable to an LED. If the cable is absent, the driver IC will not supply power for the LED. One embodiment of a keyboard and display backlight control system can be configured to allow substantially independent operation.

Abstract: The disclosed embodiments provide an apparatus that controls a current drawn from an adapter by a computer system. During operation, the apparatus senses the current drawn from the adapter using a first current sensor and a second current sensor, wherein a response time of the first current sensor is faster than a response time of the second current sensor. Then, when the current sensed using the first current sensor exceeds a predetermined high-current threshold, the apparatus limits the current drawn from the adapter to a first predetermined current limit. Additionally, when the current sensed using the second current sensor exceeds a predetermined thermal-limit current, the apparatus limits the current drawn from the adapter to the predetermined thermal-limit current.

Abstract: A system and method for enabling power applications over a single communication wire pair. In one embodiment, a data transformer is provided that has three separate windings. Two of the windings are tied to each other via high frequency pass DC-blocking capacitors, or another suitable element that creates an AC path while providing a DC block, such that the voltage forms on either ends of the DC-blocking capacitors and the signal is sent on the outer legs of each winding. A circuit measures the current draw (I) and injects a current proportional to, but smaller than, I into a third bias cancellation winding.

Abstract: A system and method for producing a family of power modules having a common footprint that enables the customer to flexibly choose a power module size without incurring the costs of a relayout of a system design. In one embodiment, a board layout can be designed using a selected power module footprint size that supports an installation of any of a plurality of power modules. The power module that is used in a board layout can be selected based on a measurement of an amount of power consumed by the one or more loads.

Abstract: A system and method for enabling power applications over a single communication wire pair. In one embodiment, a data transformer is provided that has three separate windings. Two of the windings are tied to each other via high frequency pass DC-blocking capacitors, or another suitable element that creates an AC path while providing a DC block, such that the voltage forms on either ends of the DC-blocking capacitors and the signal is sent on the outer legs of each winding. A circuit measures the current draw (I) and injects a current proportional to, but smaller than, I into a third bias cancellation winding.

Abstract: A system and method for enabling power applications over a single communication wire pair. In one embodiment, a data transformer is provided that has three separate windings. Two of the windings are tied to each other via high frequency pass DC-blocking capacitors, or another suitable element that creates an AC path while providing a DC block, such that the voltage forms on either ends of the DC-blocking capacitors and the signal is sent on the outer legs of each winding. A circuit measures the current draw (I) and injects a current proportional to, but smaller than, I into a third bias cancellation winding.

Abstract: Aspects of a method and system for operating and/or charging a battery powered USB device based on a USB port type are provided. In this regard, in a USB device comprising a power management IC and a multi-function IC, a port type detection module in the multi-function IC may determine whether the USB device is attached to a standard host port or a charging port. Additionally, a power source in the power management IC, which may supply power to the port type detection module, may be enabled upon attachment of the USB device to a USB port and disabled subsequent to determination of port type. Also, one or more portions and/or functions of the power management IC may be configured based on the determined port type. Similarly, one or more portions and/or functions of the multi-function IC may be enabled or disabled based on the determined port type.

Abstract: A system and method for enabling power applications over a single communication wire pair. In one embodiment, a data transformer is provided that has three separate windings. Two of the windings are tied to each other via high frequency pass DC-blocking capacitors, or another suitable element that creates an AC path while providing a DC block, such that the voltage forms on either ends of the DC-blocking capacitors and the signal is sent on the outer legs of each winding. A circuit measures the current draw (I) and injects a current proportional to, but smaller than, I into a third bias cancellation winding.

Abstract: Power sourcing equipment comprising: a power input; an output port; a control circuit comprising a means for sensing that a voltage component of power received at the power input is above a pre-determined threshold; a non-uniform signal source; an impedance associated with the non-uniform signal source; and an electronically controlled switch responsive to the control circuit, the electronically controlled switch being arranged to switchably operatively connect the impedance to at least momentarily be seen across the output port; the control circuit being operative responsive to an output of the means for sensing to operatively connect the impedance via the operation of the electronically controlled switch; the electronically controlled switch being operative to disconnect the impedance from being seen across the output port in the absence of the indicative output.

Abstract: A power over Ethernet controller comprising: management functionality; data send and receive functionality associated with the management functionality; priority determination functionality associated with the management functionality, the priority determination functionality being operative to determine a highest priority port requesting power; and power enabling functionality associated with the management functionality, the management functionality having a first mode of operation in which: responsive to receipt of a command via the data send and receive functionality to enable a port, the management functionality enables the determined highest priority port requesting power via the power enabling functionality; and a second mode of operation in which: responsive to receipt of a command via the data send and receive functionality to enable a specific port, the management functionality enables the specific port via the power enabling functionality.

Abstract: A redundant powering system for a powered device receiving power over communication cabling, the redundant powering system comprising: a redundant power supply comprising a first power sourcing equipment and a second power sourcing equipment; a powered device; communication cabling connecting the redundant power supply to the powered device, the communication cabling comprising a first path connecting the first power sourcing equipment to the powered device and a second path connecting the second power sourcing equipment to the powered device, the first and second paths at least partially being constituted of a single structured cable, the at least one powered device comprising at least one signature impedance, the redundant power supply being operable so that power is operably supplied to the powered device from only one of the first and second power sourcing equipment.

Abstract: A power over Ethernet controller supporting a plurality of powering modes, the power over Ethernet controller comprising: a pair of power sourcing equipments; and a control circuit; the control circuit being operative to control each of the pair of power sourcing equipment units in one of a first mode and a second mode, the first mode comprising operating the pair of power sourcing equipments as a single power sourcing equipment operable to power a single powered device over communication cabling, and the second mode comprising operating each of the power sourcing equipments of the pair independently so as to each be operable to power an associated powered device over communication cabling.

Abstract: A method of determining an effective resistance between a power sourcing equipment and a powered device, the powered device exhibiting an interface and an operational circuitry, the method comprising: prior to connecting power to the operational circuitry of the powered device, impressing two disparate current flow levels (I1, I2) between the power sourcing equipment and the powered device; measuring the voltage at the powered device interface (VPD1, VPD2) responsive to each of the impressed disparate current levels; measuring the voltage at the power sourcing equipment (VPSE1, VPSE2) responsive to each of the impressed disparate current levels; and determining the effective resistance between the power sourcing equipment and the powered device responsive to the VPD1, VPD2, VPSE1, VPSE2, I1 and 12.