Embodiments of this invention provide for a portable computer that determines whether an accessory device is actively connected to it. In one embodiment, the portable computer may include a signal line accessible through an output of the portable computing device. The signal line may be connected to a communication device such as a communication cradle. The portable computer may detect a signal on the signal line to determine whether the communication device is actively connected to the portable computer. If the communication device is actively connected, the portable computer suspends implementation of a time-out feature that would otherwise reduce power consumption of the portable computer.

System and method for detection of an accessory device connection status

Disclosed is a battery charger that can be connected in series to a power feed line, which lies between an external power source and an electric/electronic device, and that monitors the power consumption state of the electric/electronic device and begins and halts the charging of a battery in consonance with the power consumption state. Since a battery charger according to the present invention can be inserted in series into a power feed line that lies between an AC/DC adaptor and an electric/electronic device, the wiring arrangement is not complicated and a spare battery can be automatically charged. Since the charging is performed only during a period in which power consumption by the electric/electronic device is relatively low, the charging operation does not affect the system operation. As the battery charger does not require AC to DC conversion circuit, it is compact and light and is suitable for use along with a portable device. Further, when the spare battery pack is carried with being attached into the battery charger, the volume is not great, and as the terminal portions of the battery are covered and are protected from coming into contact with foreign conductive material, the possibility that the electrodes of the battery will be short-circuited can be prevented. To use a notebook computer while staying at a hotel on a business trip, a user need merely connect in series an AC/DC adaptor, a Travel Quick Charger, and a notebook computer in the named order via a power supply cord. The spare battery can be attached into a Travel Quick Charger while being carried to the destination.

Battery charger for an electronic device and a spare battery

The present invention provides a search window delay tracking procedure for use in a multipath search processor of a CDMA radio receiver. A channel impulse response is estimated for a received signal containing plural paths, each path having a corresponding path delay. A search window defines a delay profile that contains the plural paths of the received signal. A mean or average delay is calculated for the estimated channel impulse response (CIR), and an error is determined between the mean CIR delay and a desired delay position corresponding to the center of the CIR search window. An adjustment is made to reduce that error so that the center of the search window and the mean CIR delay are aligned. The error may be processed either linearly (in one embodiment) or non-linearly (in another embodiment) to minimize the error and to reduce an influence of noise. A non-linear filtering process includes calculating a delay spread from the mean CIR delay calculated for successive processing cycles of a window delay tracking procedure corresponding to each new input. A difference is determined between the successive delay spreads. Adjustment signal is set equal to the error signal if the difference is less than or equal to a threshold. Alternatively, the adjustment signal is set to zero if the difference is greater than the threshold. Consequently, if the delay spread in the current iteration is significantly different from the delay spread in the previous iteration, the new error sample calculated in the current iteration is considered unreliable, and no adjustment is made.

Search window delay tracking in code division multiple access communication systems

A fault tolerant power supply system includes a plurality of devices coupled to a common power distribution bus. The devices are arranged and connected in a hierarchical order. The system provides that the devices of higher rank or position in the hierarchy to obtain priority in drawing power from the bus. Each device is coupled to the next adjacent device via a control status line that indicates whether there has been a failure of the power supply of any device higher up in the hierarchy. In the event that the local power supply of a device fails, it can be selectively connected to the power distribution bus to draw power, only if the control status line indicates that there have no failures in the devices having a higher hierarchical rank. Once connected to power distribution bus, if a higher ranking device should experience a power supply failure, the device will be disconnected from the power distribution bus and the higher ranking device connected to the power distribution bus.

Fault tolerant power supply system

The present invention relates to a system and method for reducing the power consumption of a computer system, more specifically a notebook computer system. The system comprises a programmable frequency generator and a programmable power supply which alters the current operating frequency and voltage of the computer's microprocessor to match current operating conditions. If the microprocessor is not doing any meaningful work, the programmable frequency generator and the programmable power supply can reduce both the operating frequency and voltage thereby lowering the power consumption of the computer system based on the formula: power=voltage 2 ×frequency. It should be noted that the programmable frequency generator and the programmable power supply may be attached to other system components in the computer system that consume a large amount of the computer system's power.

System for reducing the power consumption of a computer system and method therefor

A power system fault handling mechanism for portable electronic devices having multiple power supplies. A safety-net circuit is triggered when a power fault condition is detected. The safety-net circuit is a diode-based bridging circuit which couples all available power supplies to the power load, yet avoids feeding power back from any of the supplies to one another. This ensures that the load continues to receive power after a fault condition occurs without interruption. A microcontroller may then implement routines to switch to a working power supply so that the device may resume normal operation. The power system fault detection mechanism thus allows for the switching between system power supplies without disrupting a running process.

Eva Henin

Papers

Power system configuration and recovery from a power fault condition in a computer system having multiple power supplies