Abstract: Power control circuitry and method for controlling a variable output DC power source. The power control circuitry may comprise a first comparator to compare a signal representative of an output current level of the variable output DC power source with a threshold level and provide a first output signal in response to the comparison. The power control circuitry may further comprise threshold input circuitry to provide the threshold level to the first comparator, the threshold level being a fixed threshold level if an output voltage of the variable output DC power source is less than or equal to a first fixed voltage level, the threshold level being a variable threshold level if the output voltage is greater than the first fixed voltage level.

Abstract: Full capacity determination in a battery gas gauge. Operations include measuring instantaneous open circuit voltage levels during an open circuit time interval for a specific battery cell and correlating such measurements to estimate values. Such estimated values may then be correlated to associated relative state of charge levels. Finally, a full capacity calculation can be made based on the associated relative state of charge levels. A plurality of full capacity determinations may also be made and compared to each other to assess the reliability of such determinations.

Abstract: A power management topology for portable electronic devices that includes a feed-enabled AC/DC adapter that receives feedback data from a charge controller associated with the portable device. The feedback data can include battery charging current, battery voltage, or power requirements of the portable device. Using the feedback data, the external AC/DC adapter can adjust the DC output to meet the charging requirement of the battery and/or the power requirements of the portable device.

Abstract: A monitoring circuit for accurately monitoring a voltage level from each of a plurality of battery cells of a battery pack includes an analog to digital converter (ADC) and a processor. The ADC is configured to accept an analog voltage signal from each of the plurality of battery cells and convert each analog voltage signal to a digital signal representative of an accurate voltage level of each battery cell. The processor receives such signals and provides a safety alert signal based on at least one of the signals. The ADC resolution may be adjustable. A balancing circuit provides a balancing signal if at least two of the digital signals indicate a voltage difference between two cells is greater than a battery cell balance threshold. An electronic device including such monitoring and balancing circuits is also provided. Various methods are also provided.

Abstract: An integrated controller for the detection and operation of both PC Cards, smart cards and passive smart card adapter cards. In one aspect, the invention detects the presence of standard expansion cards or passive smart card adapters by utilizing the reserved detection and voltage selection signal area defined by the PC Card specification. In another aspect, the invention provides an integrated controller that includes logic to operate either a standard expansion card or a passive smart card adapter by reassigning certain PC Card signal lines to operate a standard expansion card or a passive smart card adapter, thereby eliminating the need to provide pins in addition to those defined by the PC Card specification.

Abstract: A charging circuit for controlling a system charging parameter provided to a host of rechargeable batteries, wherein the host of batteries includes at least a first battery and second battery that may be coupled in parallel. The charging circuit provides for fast charging of rechargeable batteries in parallel. Independent current and voltage sensing for each battery enables parallel charging of batteries at different charging currents. The charging circuit may be configured to accept either analog or digital signals from an associated power management unit.

Abstract: A reconfigurable flash media reader system provides a flash media reader that accepts both asynchronous and synchronous flash media cards. The reader identifies the card type of the inserted flash media card and notifies the host computer of the card type. The host computer has a list of interface information for different types of flash media cards and references the card type in the list and sets the proper baud rate on the reader. If the flash media card is a synchronous card, data that is to written into the flash media card is gathered and converted to the proper card IO strobes for the card type which are interleaved with the proper card clock strobes for the card type into a bit stream in a bulk transfer packet. The reader extracts the data bit stream from said bulk transfer packet and clocks the data bit stream into the flash media card using the baud rate as a reference clock.

Abstract: A DC-to-DC converter includes a comparator, a driver, and a pair of switches. The comparator compares the output voltage with a reference voltage signal and generates a PWM signal. The driver drives the switches so as to force the output voltage to follow the reference signal. In a multiphase architecture, two or more such converter circuits are incorporated to minimize the output voltage ripple and further reduce the recovery time. In a two-phase architecture, two reference signals are phase-shifted by 180 degrees. In an N-phase architecture, the reference signals are phase-shifted by 360/N degrees.

Abstract: A compensated current generator includes a first current source and a second current source coupled in series. The first and second current sources have temperature coefficients with opposite signs to produce a temperature compensated current. The first current source may be a peaking current source biased by a bias signal to operate a peak of its transfer characteristic curve to enhance power supply rejection. An associated method is also provided.

Abstract: A power converter may include a transformer having a primary winding and a secondary winding. A first high side switch and a first low side switch may be coupled in series along a first path of a full bridge circuit, having a first node between the first high side switch and the first low side switch. The power converter may also comprise a second high side switch and a second low side switch coupled in series along a second path of the full bridge circuit, having a second node between the second high side switch and the second low side switch. The power converter may further comprise a first path capable of providing a first rectifier drive signal from the first node to a second rectifier switch, and a second path capable of providing a second rectifier drive signal from the second node to a first rectifier switch.

Abstract: A selector circuit configured to select among a DC power source and a plurality of batteries for an electronic device. The selector circuit is responsive to an output signal from an associated power management unit. The selector circuit is further configured to permit parallel operation of two or more of the batteries. The selector circuit may further act to independently verify power conditions and override instructions from the PMU in certain instances to enhance power supply safety and battery life such as by preventing inter battery current flow from a higher potential battery to a lower potential battery coupled in parallel.

Abstract: A DC to DC converter having improved transient response, accuracy, and stability. The DC to DC converter includes a comparator configured to compare a reference signal with a second signal. The reference signal has a DC offset determined, at least in part, by a DC reference voltage source. The second signal is representative of an output voltage of the DC to DC converter. The comparator is further configured to provide a control signal to a driver that drives the output voltage of the DC to DC converter in response to a comparison of the reference and second signal. The DC to DC converter further includes an accuracy circuit to enhance accuracy of the DC to DC converter. The DC to DC converter may further include a stability circuit to enhance stability of the DC to DC converter.

Abstract: A controller for controlling at least two power circuits comprises a pulse generator and a selector. The pulse generator generates a first pulse signal which is coupled to a first power circuit of the at least two power circuits for initiating the operation of the first power circuit. The first power circuit then outputs a second pulse signal to a second power circuit of the at least two power circuits to initiate the operation of the second power circuit. The selector generates a reference signal which is coupled to each of the at least two power circuits for indicating a number of power circuits controlled. The controller is used to control energy supplying to an electrical circuit comprising multiple inverters and is more particularly to provide phase shifts to the electrical circuit. Usually, the electrical circuit is applied to display devices, such as liquid crystal display monitors, liquid crystal display computers and liquid crystal display televisions.

Abstract: A selector circuit configured to select among a DC power source and a plurality of batteries for an electronic device. The selector circuit is responsive to an output signal from an associated power management unit. The selector circuit is further configured to permit parallel operation of two or more of the batteries. The selector circuit may further act to independently verify power conditions and override any instructions from the PMU in certain instances to enhance power supply safety and battery life. A power supply block including the selector circuit and an electronic device including the power supply block is also provided. The selector circuit may be integrated with a charging circuit on one integrated circuit.

Abstract: A controller for a DC to DC converter is configured to provide a PWM signal in a first state during a first time interval based on an input voltage less a voltage level representative of an output voltage of the DC to DC converter. The controller may provide the PWM signal in the first state based on the time it takes to charge an energy storage element of the controller to a predetermined level. The controller may also provide an estimator of a zero inductor current level in an associated inductor when the energy storage element is completely discharged. The controller may also be a digital controller that counts time pulses to provide the PWM signal. A DC to DC converter including such a controller and associated methods are also provided.

Abstract: Level shifting and amplified level shifting circuit topologies are provided that include two or more level shifting or amplified level shifting circuits. The level shifting circuits receive a variable and fixed input and generate a variable and fixed output that are level shifted with respect to the input signals. The amplified level shifting circuits receive a variable and fixed input and generate a variable and fixed output that are level shifted and amplified with respect to the input signals. These circuits may be utilized to form a detection circuit that detects a difference in the output signals.

Abstract: A dual mode smart card controller is provided. In one embodiment, a USB and ISO7816 smart card controller is provided that determines the type of card that is inserted into a slot. If the smart card is a USB smart card, the controller is adapted to pass control of the smart card to an external PC host USB hub circuit. If the smart card is an ISO7816 card, then control is handled by the dual mode controller. In another embodiment, the controller includes an embedded USB hub circuit to permit the controller to directly control both USB and ISO7816 smart cards. Exemplary control sequencing includes monitoring a C4 signal line for a preselected time period, or generating an enable signal if a USB smart card is detected.

Abstract: An enabling circuit includes a comparison circuit configured to compare a feedback signal representative of a charge of an energy storage element of a regulating circuit with a reference charge and provide an output in response to the comparison to enable the regulating circuit to switch from a first state to a second state if the charge of the energy storage element is less than the reference charge. The enabling circuit may also be used to enable a synchronous rectifier converter to provide a charging current to a battery in a battery charging system of an electronic device thereby avoiding negative voltage transients that may otherwise occur at the output of the synchronous rectifier converter. Various methods are also provided.

Abstract: An integrated circuit inverter controller that includes at least one input pin that is configured to receive two or more input signals. The input pin may be multiplexed so that the appropriate input signal is directed to appropriate circuitry within the controller to support two or more functions of the controller. Alternatively, the input signals may be present in differing time periods so that a single pin can support two or more functions. Multifunctional or multitasked pins reduce the overall pin count of the inverter controller.

Abstract: The present invention provides an inverter controller comprising a drive circuit that generates a plurality of switch drive signals for inverter applications. In some exemplary embodiments, the drive circuit operates by reversing the command level of an error signal. In other embodiments, the drive circuit operates by using a half period of a sawtooth signal. In still other embodiments, the drive circuit operates by using a double period opposite shifting pulses method. The present invention also provides a PWM signal generator circuit that generates periodic PWM switch drive signals symmetrical to the minimum or maximum of a sawtooth waveform.