Abstract: In a method for charging a rechargeable battery an ultra-fast charging of in particular NiMH-batteries is achieved by controlling the charging current and the charging voltage, respectively, such that the temperature of the battery is constant. Due to the constant temperature control it is avoided that unnecessary electrical energy is waisted for heating the battery. The end of charging is preferably determined by detecting a predetermined change of the charging efficiency.

Abstract: A cordless position detection apparatus includes a position detection area and a pointer. A plurality of conductors are arranged side-by-side in the position detection area. The position detection area has a selection circuit for selecting single conductors, and a transmitting circuit that provides a transmitting signal having at least one harmonic to a selected conductor. A pointer for use with the position detecting area includes a resonance circuit which is tuned to an harmonic of the transmitting signal. The pointer is excited by the transmitting signal to oscillate and radiates a receiving signal. A receiving circuit in the detection apparatus detects the receiving signal in a selected conductor and processing means uses this received signal to determine a position indicated by the pointer.

Abstract: A contactless inductive data transmission system provides bidirectional signal transfer between a sending-and-receiving station and one or more batteryless transponders. A high-frequency signal from the sending-and-receiving station is pulse width modulated for data transmission to a transponder and provides a system clock, which is extracted in both the sending-and-receiving station and in the transponder for synchronization, and provides the electrical power for operation of the transponder. The pulse width modulated signal is demodulated in the transponder for triggering a response wherein a modulating signal is applied by load modulation to the pulse width modulated high-frequency signal to form an information-carrying load modulated high-frequency signal, which is demodulated in the sending-and-receiving station.