Fujitsu Corporation

Fujitsu Microelectronics Limited

Kenichi Minobe

Atsushi Matsuda

Hiromi Nanba

Masashi Okubo

Tohru Mizutani

Yoshinori Yoshikawa

Atsushi Hitaka

A semiconductor device includes a first analog circuit () adapted to a first performance, and a second analog circuit () realizing a second performance higher than the first performance by cooperating with the first analog circuit. It becomes possible to switch circuit characteristics appropriately in accordance with a requested performance while suppressing an increase of a circuit scale, by operating the first analog circuit and interrupting a power supply to the second analog circuit when the first performance is requested, and by operating the first analog circuit and the second analog circuit together when the second performance is requested to thereby share the first analog circuit.

Semiconductor device, radio terminal device, and radio communication equipment

An analog-to-digital converter conventionally performing a detection of a differential offset is replaced by a comparator. A reference voltage is input to a terminal on one side of the comparatorand each of a pair of differentials of a differential voltage signal is input to the other terminal one by one. Then, a setup of voltages of both of the pair of differentials to closer values to the reference voltage makes both voltages of the pair of differentials eventually the same, thereby making it possible to correct a differential offset.

Differential offset correction circuit

An integrated circuit includes an analog signal output unit which converts a digital output signal into at least one analog output signal, and outputs the at least one analog output signal, an analog signal input unit which converts at least one analog input signal received from an exterior into a digital input signal, a switch circuit which provides at least one signal path through which the at least one analog output signal is supplied from the analog signal output unit to the analog signal input unit as the at least one analog input signal, and an offset adjustment control circuit which supplies an output offset from the analog signal output unit to the analog signal input unit via the at least one signal path so as to detect the digital input signal inclusive of the output offset and an input offset, and cancels offsets of the analog signal output unit and the analog signal input unit in response to the output offset and the input offset obtained from the detected digital input signal.

Digital-analog-conversion circuit having function of automatic offset adjustment

A semiconductor device with temperature compensation functions and a temperature change detecting device which detect temperature changes accurately, without requiring extra mounting space. A sensor unit is composed of first semiconductor components (first-type resistors) having a certain temperature coefficient and second semiconductor components (second-type resistors) having a different temperature coefficient. They are located in the vicinity of a processing circuit that needs temperature compensation. Changes in the temperature of the processing circuit are detected by a temperature change detector which observes a certain property (e.g., resistance) of the first and second semiconductor components constituting the sensor unit. A temperature corrector corrects functions of the processing circuit according to the detection result provided from the temperature change detector.

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Kawasaki, Japan

Kenichi Minobe