Abstract: A circuit is provided for time division duplexing with a frequency hopping technique and has a total of just two frequency synthesizers for the transmission and reception paths and only one up-converter in the transmission path. The UHF synthesizer frequency is additionally subjected to frequency division prior to insertion as a heterodyne frequency of the assigned converter in the transmission and reception paths, which, owing to the shorter transient recovery times, makes it possible to utilize the UHF frequency synthesizers at different frequencies for the transmission and reception slots, respectively. A particular application is in cordless telephones.

Abstract: The invention rests on the idea that the information for controlling an EC-motor is taken from the adjustment or position of the control unit, which can be ascertained by means of a position indicator, such as a potentiometer, Hall indicator, etc. The current pattern for the EC-motor can thereafter, for example, be determined in a microcomputer disposed in the motor control for the control unit, without the motor having a rotor position determination.

Abstract: The invention relates to a method for providing feedback on the current driving state of a vehicle having a plurality of driving system devices to the driver, and a device for carrying out the method.

Abstract: In a brushless direct-current drive with a synchronous motor (10), which has a stator (12) that supports a multi-phase stator winding (15) and a rotor (13) equipped with permanent magnet poles (20), and with a switch unit (11), which precedes the stator winding (15), for commutating the stator winding (15), in order to produce a fail-silent behavior, a field excitation winding (21) is disposed in the rotor (13), which winding can be supplied with current in the event of a malfunction so that it generates a magnetic flux oriented in the opposite direction from the magnetic flux of the permanent magnet poles (20) (FIG. 2).

Abstract: A method and circuit for compensation control of offset voltages of a radio receiving circuit integrated in a circuit module that can be used in receiver and transceiver chips for portable mobile radio transceivers, for example in GSM or PCN/PCS systems. In the course of offset voltage compensated in the baseband of a radio receiver, the charge state of a capacitor, which is switched on in a sample-and-hold circuit by predetermined, constant control pulses is evaluated on-chip. The evaluation result is used to match the charging current of a sample operational amplifier to the respective charge state of the capacitor, thereby achieving a minimal compensation time with stable regulation.

Abstract: A frequency synthesizer for a radio terminal with which a dual-band and/or dual-mode switchover is possible in a simple manner. The frequency synthesizer has a double phase-locked loop with a high-frequency portion and an intermediate-frequency portion, each with one divider and one counter in a feedback branch. There is at least one memory for holding a plurality of divider values for the counter in the intermediate-frequency portion. The counter in the high-frequency portion is coupled to the memory in such a way that when a new divider value is written into the counter of the high-frequency portion, an associated divider value from the memory is written into the counter of the intermediate-frequency portion. In this way, the frequency generated by the intermediate-frequency divider is adapted to the frequency generated in the high-frequency portion in such a way that the requisite operating frequencies of each active mobile radio system are set automatically.

Abstract: A balanced voltage reference circuit has a transistor that is operated as an emitter follower and to whose base two resistors are connected in series for beta compensation of the balanced circuit. One end of the smaller resistor which faces away from a transistor base, the smaller resistor being split into two resistor elements, is connected inside the chip to a signal point of an amplifier circuit whose operating point can be adjusted. In which case, one end of an integrated capacitance is connected, as a parallel element of an RC filter, between the two resistor elements of the smaller resistor.

Abstract: An integrated circuit configuration for generating a reference current by bipolar technology includes a transistor of one conduction type having a control terminal being acted upon by a reference voltage and having a load path. An externally connectable resistor is to be connected between the load path of the transistor and a reference potential. A current mirror configuration has an input side connected between the load path of the transistor and a supply voltage source and has an output for picking up a reference current.