Abstract: A control circuit for light emitting diode (LED) of display includes a central processing unit (CPU), an AND gate, and a driving circuit. The CPU comprises a general purpose input output (GPIO) contact which outputs an instant high level voltage when a battery is installed into a portable electronic device. The AND gate includes a first input contact connected to the GPIO contact, a second input contact connected to a system power supply, and a first output contact. The system power supply outputs a low level voltage when the electronic device is powered off and outputs a high level voltage when the electronic device is powered on. The driving circuit includes a second output contact connected to an anode of the LED, a feedback contact connected to a cathode of the LED and an enable connected to the first output contact.

Abstract: A method for use in electronic design software efficiently and optimally produces minimized or reduced register flip flop area or number of registers/flip flops in a VLSI circuit design without changing circuit timing or functionality. The method dynamically generates constraints; maintains the generated constraints as a regular tree; and incrementally relocates registers/flip flops and/or the number of registers/flip flops in the circuit design.

Abstract: The invention relates to a centrifugal pump connection device for electrical submersible pump unit; two or more centrifugal pumps are fixedly connected successively from top to bottom, the lower end of a centrifugal pump body being a connecting flange and a rabbet at the lower end of the connecting flange inserting in the upper inner bore of an adjacent centrifugal pump body, the contact surface between the connecting flange and the centrifugal pump body is a spherical surface, and the used washer of a bolt is a disc washer; the spherical surface of the connecting flange is a convex spherical surface, and the spherical surface of the upper end of the centrifugal pump body is a concave spherical surface.

Abstract: A voltage conversion circuit for a charging device includes a voltage-stabilizing circuit and a switching circuit. The voltage-stabilizing circuit includes a voltage stabilizer circuit and a feedback resistor, the voltage stabilizer circuit comprises an input pin, an output pin, and a feedback pin. The switching circuit includes a switch and at least two divider resistors, the switch comprises at least two data input terminals, a data output terminal, and two control terminals. The input pin is connected to a power source, and the feedback resistor is connected between the feedback pin and ground. The data input terminals are respectively connected to the output pin through one of the divider resistors, the data output terminal is connected between the feedback pin and the feedback resistor, the two control terminals are capable of receiving control signals to control the data output terminal to selectively connect to one of the data input terminals.

Abstract: A portable electronic device includes an earphone jack circuit for receiving an earphone plug, a control circuit and a switch circuit. The control circuit sends audio to or receives audio from the earphone plug by the earphone jack. The switch circuit is set between the earphone jack and the control circuit including a first mode and a second mode. The control circuit identifies a type of the earphone plug, and switches the switch circuit to a corresponding mode according to the type of the earphone plug.

Abstract: A power management circuit for managing power of an electronic device includes a regulator and a protection circuit. The regulator converts an input voltage into a corresponding rated voltage and includes an enable pin and an output pin. The enable pin receives a voltage signal to enable or disable the regulator, and the output pin selectively outputs the rated voltage. When the electronic device is implemented as a slave universal serial bus (USB) device and the enable pin receives a low voltage signal, the regulator is disabled, and the protection circuit receives an output voltage. When the electronic device is implemented as a USB host and the enable pin receives a high voltage signal, the regulator is enabled, and the output protection circuit outputs the rated voltage.

Abstract: A method for making a carbon nanotube composite preform includes following steps. A substrate is provided. Carbon nanotubes are formed on the substrate. The carbon nanotubes and the substrate are placed in a solvent for a predetermined time. The carbon nanotubes and the substrate are drawn from the solvent. The carbon nanotubes and the substrate are dried.

Abstract: An earphone jack circuit includes an earphone jack configured to receive an earphone plug, a frequency modulation (FM) signal processing circuit electrically connected to the earphone jack, and an amplifying circuit. The FM signal processing circuit includes a first matching circuit electrically connected to the earphone jack, and an amplifying circuit electrically connected to the first matching circuit. The first matching circuit receives an initial FM signal from the earphone jack and executes a first filtering process for the initial FM signal when the earphone plug is inserted into the earphone jack. The amplifying circuit amplifies the filtered FM signal.

Abstract: A charging circuit includes a main control microchip, a charging integrated circuit, and a current control circuit. The main control microchip includes a power-on pin connected to a charging device. The charging integrated circuit comprises a power input pin and a current limit pin, wherein the power input pin is connected to the charging device, and the charging integrated circuit is capable of limiting current. The current control circuit comprises a transistor, a first current limiting resistor and a second current limiting resistor, a base of the transistor is connected to the main control microchip, the first current limiting resistor is connected between the current limit pin and ground, and the second current limiting resistor is connected between the current limit pin and a collector of the transistor, the main control microchip is operable to output control signals to enable or disable the transistor.

Abstract: A carbon nanotube composite preform includes a substrate and a plurality of carbon nanotubes formed thereon. Each carbon nanotube includes a first end adjacent to the substrate and a second end away from the substrate. Gaps between the second ends of the carbon nanotubes are bigger than gaps between the first ends thereof. The method for making the carbon nanotube composite preform includes the following steps: (a) providing a substrate; (b) forming a plurality of carbon nanotubes (e.g., a carbon nanotube array) on the substrate; (c) placing the carbon nanotubes and the substrate in a solvent for some time; (d) removing the carbon nanotubes and the substrate from the solvent; (e) drying the carbon nanotubes and the substrate to form a carbon nanotube composite preform.

Abstract: A control circuit for light emitting diode (LED) of display includes a central processing unit (CPU), an AND gate, and a driving circuit. The CPU comprises a general purpose input output (GPIO) contact which outputs an instant high level voltage when a battery is installed into a portable electronic device. The AND gate includes a first input contact connected to the GPIO contact, a second input contact connected to a system power supply, and a first output contact. The system power supply outputs a low level voltage when the electronic device is powered off and outputs a high level voltage when the electronic device is powered on. The driving circuit includes a second output contact connected to an anode of the LED, a feedback contact connected to a cathode of the LED and an enable connected to the first output contact.

Abstract: A portable electronic device includes a battery, a central processing unit (CPU), and voltage converting circuit. The battery includes an erasable programmable read-only memory (EPROM) and a signal terminal connected to the EPROM. The CPU includes a read/write control terminal. The voltage converting circuit includes a first power terminal connected to a first power supply, a second power terminal connected to a second power supply, a first port connected to the read/write control terminal through a 1-wire bus, and a second port connected to the signal terminal.

Abstract: A method of controlling a base station, a network controller, a base station, a telecommunications network and a computer program product are disclosed. A method of controlling a base station (140; 150; 160) in a mobile telecommunications network (220) comprises the steps of: (i) determining whether a base station within the mobile telecommunications network is not supporting user equipment (110; 120; 130) and, if so, then (ii) signalling the base station to reduce its transmission power. An assessment is made as to whether a base station is currently supporting user equipment. If a base station is currently supporting user equipment, then that base station is unlikely to be a candidate to have its power reduced since support to that user equipment needs to be maintained. However, if a base station is not supporting user equipment, then that base station would appear to be a likely candidate for transmission power reduction, thereby saving power in the network at those locations where it is possible to do so.

Abstract: A femto cell base station and a method are disclosed. The method comprises the steps of: a) monitoring data transmission antenna weights used during wireless data transmissions over a femto cell data channel between a femto cell base station and user equipment; b) deriving broadcast channel antenna weights from the data transmission antenna weights; and c) forming the femto cell broadcast channel beam using the broadcast channel antenna weights. The femto cell broadcast channel beam is adapted to minimize interference. The femto cell broadcast channel beam may then be formed using those broadcast channel antenna weights in order to direct and restrict the size of the broadcast channel beam and reduce the likely interference caused by the femto cell to other femto cells and to a macro cell.

Abstract: A method is provided of controlling transmission power of a picocell base station. The method comprises the steps of the picocell base station: transmitting a signal at a first power; receiving a report from a mobile terminal that the signal is received within a predetermined quality range; dependent upon receiving said report instructing the mobile terminal to report as to the number of neighboring macrocells detected by the mobile terminal; and controlling the transmission power of a further signal dependent upon said number.

Abstract: In a wireless telecommunications network, a Code Division Multiple Access (CDMA) scheme is applied to data to encode it. The encoded data transmitted in the uplink using an Orthogonal Frequency Division Multiplexing (OFDM) frame structure including a cyclic prefix (CP). The CDMA encoded data may be time multiplexed with Single Carrier-Frequency Division Multiple Access (SC-FDMA) transmissions. The CDMA transmissions may be used for relatively small payloads, such as those associated with voice traffic and control signals, and the SC-FDMA transmissions used for higher date rate transmissions. This enables autonomous transmission, without scheduling, for smaller payloads. A transmitter includes a selector 3 for performing time multiplexing in the uplink, the required mode being indicated by the Hybrid Automatic Repeat Request (HARQ) ID. A first branch 1 carries SC-FDMA data and a second branch 2 carries data to be transmitted as a CDMA scheme. A CAZAC code may be used in encoding the CDMA data.

Abstract: A charging circuit includes a main control microchip, a charging integrated circuit, and a current control circuit. The main control microchip includes a power-on pin connected to a charging device. The charging integrated circuit comprises a power input pin and a current limit pin, wherein the power input pin is connected to the charging device, and the charging integrated circuit is capable of limiting current. The current control circuit comprises a transistor, a first current limiting resistor and a second current limiting resistor, a base of the transistor is connected to the main control microchip, the first current limiting resistor is connected between the current limit pin and ground, and the second current limiting resistor is connected between the current limit pin and a collector of the transistor, the main control microchip is operable to output control signals to enable or disable the transistor.

Abstract: A power management circuit for managing power of an electronic device includes a regulator and a protection circuit. The regulator converts an input voltage into a corresponding rated voltage and includes an enable pin and an output pin. The enable pin receives a voltage signal to enable or disable the regulator, and the output pin selectively outputs the rated voltage. When the electronic device is implemented as a slave universal serial bus (USB) device and the enable pin receives a low voltage signal, the regulator is disabled, and the protection circuit receives an output voltage. When the electronic device is implemented as a USB host and the enable pin receives a high voltage signal, the regulator is enabled, and the output protection circuit outputs the rated voltage.

Abstract: A voltage conversion circuit for a charging device includes a voltage-stabilizing circuit and a switching circuit. The voltage-stabilizing circuit includes a voltage stabilizer circuit and a feedback resistor, the voltage stabilizer circuit comprises an input pin, an output pin, and a feedback pin. The switching circuit includes a switch and at least two divider resistors, the switch comprises at least two data input terminals, a data output terminal, and two control terminals. The input pin is connected to a power source, and the feedback resistor is connected between the feedback pin and ground. The data input terminals are respectively connected to the output pin through one of the divider resistors, the data output terminal is connected between the feedback pin and the feedback resistor, the two control terminals are capable of receiving control signals to control the data output terminal to selectively connect to one of the data input terminals.

Abstract: A portable electronic device includes an earphone jack circuit for receiving an earphone plug, a control circuit and a switch circuit. The control circuit sends audio to or receives audio from the earphone plug by the earphone jack. The switch circuit is set between the earphone jack and the control circuit including a first mode and a second mode. The control circuit identifies a type of the earphone plug, and switches the switch circuit to a corresponding mode according to the type of the earphone plug.