Atmel Germany Gmbh

Atmel Corporation

Kathrein Se

Udo Karthaus

Ulrich Friedrich

Martin Fischer

Dirk Ziebertz

Stefan Markus Schabel

Herbert Knotz

Peter Kolb

Karl-Josef Gropper

Knut Brenndoerfer

A mixing circuit is provided that includes a charge circuit, an oscillating circuit inlet step which is connected to a circuit which feeds an oscillating signal, and a signal inlet step. The oscillating circuit inlet step comprises at least two bipolar-transistors and the emitters thereof are connected to a constant potential which is independent from the oscillating signal. The mixing circuit is used, preferably, in a base station or a mobile radio device of a cellular radio network.

Mixer circuit, receiving circuit, transmitting circuit, and method for operating a mixer circuit

A CMOS current mirror is provided that includes a current input, an input transistor, whose conductivity path is located between the current input and a reference potential terminal, a current output, an output transistor, whose conductivity path is connected to the reference potential terminal and which supplies the current output with an output current, a gate node common for both transistors, and a supply potential terminal. The current mirror further includes a first additional transistor, whose conductivity path is located between the supply potential terminal and the gate node and whose gate terminal is connected to the current input, and a second additional transistor, whose conductivity path is located between the gate node and the reference potential terminal and whose gate terminal is connected to the gate node.

High-speed CMOS current mirror

An integrated quartz oscillator circuit is disclosed having a capacitive voltage divider, which has a first capacitor and a second capacitor, as well as having a first transconductance amplifier, which is placed in a loop connecting a first terminal and a second terminal of the first capacitor. An input of the first transconductance amplifier is connected to a center tap between the first capacitor and the second capacitor, an output of the first transconductance amplifier is connected to the first junction of the first capacitor, and the quartz oscillator circuit has a conductive element connected parallel to the second capacitor.

Integrated quartz oscillator circuit

An amplifier array includes a servo amplifier, which has a reference signal input, a return signal input, and an output signal connection, which supplies an output signal path, a reference signal generator, which supplies reference signals with different level heights to the reference signal input, and with a return, which supplies a signal, attenuated by a value of the feedback attenuation, from the output path as a return signal to the return signal input, whereby the servo amplifier supplies an amplified difference between the reference signal and return signal in the output signal path. The amplifier array has a connectable bypass gain path, which in the connected state is supplied phase-coupled to the reference signal generator and which supplies a bypass output signal in the output path.

Signal amplification method and amplifier array

A circuit arrangement for phase modulation in an input circuit of a backscattering transponder includes a varactor and at least one capacitor connected in series between two antenna terminals, and at least two voltage sources selectively connected through at least two switches to at least one terminal of the varactor. A control unit selectively opens and closes the switches in response to the data to be phase-modulated onto the backscattered signal. By selectively connecting the different voltage values of the respective voltage sources to the varactor terminal(s) through the switches, the capacitance of the varactor and correspondingly the input impedance of the input circuit are thereby varied, so as to provide respective different phase positions of the phase modulation.

Circuit arrangement and method for phase modulation in a backscattering transponder

A circuit arrangement for deriving electrical power from a received electromagnetic field to power a transponder includes a detuning unit connected between two antenna terminals for limiting the power absorbed by the antenna. The detuning unit includes a component having an impedance that passively varies or is actively varied dependent on the field strength of the field prevailing at the antenna. One arrangement of the detuning unit includes two varactor diodes connected anti-parallel between the antenna terminals. Another arrangement of the detuning unit includes a varactor arranged in series between two capacitors between the antenna terminals, a field strength detector, and a controllable voltage source connected to apply to the varactor a control voltage that varies depending on the detected field strength. Thereby, the input impedance varies depending on the field strength, to achieve impedance matching for a low field strength, and a mis-matched condition for a high field strength.

Circuit arrangement and method for deriving electrical power from an electromagnetic field

A receiving/backscattering arrangement for carrying out a contactless data transmission includes an integrated circuit having two antenna contacts, a series arrangement of three high quality capacitances connected between the two antenna contacts, whereby the middle capacitance is an MOS varactor, a controllable variable voltage source connected across the MOS varactor, and a control unit that controls the voltage source. The receiving/backscattering arrangement is especially a passive transponder with a rectifier connected between the antenna contacts, or a semi-passive transponder including a battery or solar cell, to provide the required supply voltage for the circuit. The arrangement achieves a large communication range, for receiving and modulating an interrogation signal, and backscattering the modulated response signal with a high efficiency and low losses. The integrated circuit structure is compact and economical.

Growing community of inventors

Ulm, Germany

Udo Karthaus