Abstract: A variation detection device has a processor, an AD converter converting a signal voltage output from a sensor to generate an AD converted value and outputting the AD converted value to the processor, a temperature sensor detecting a temperature of the sensor, and a memory storing a table which indicates a relationship between temperatures and initial values. When receiving the AD converted value, the processor identifies a temperature of the sensor based on an output of the temperature sensor, reads out an initial value corresponding to the identified temperature from the table, and calculates a variation between the initial value and the AD converted value.

Abstract: A data communication device includes a receiving circuit configured to receive a data signal in an active state. An intermittent activation control circuit activates the receiving circuit into the active state in a predetermined time interval. A control unit operates in response to the data signal received by the receiving circuit. Also, the control unit controls the time interval of the intermittent activation control circuit.

Abstract: A transmitter module has a sensor module that includes a plurality of sensors and operates intermittently, a signal processor module that permits transmission of an output of the sensor module to a receiver module at given permission timings, a radio transmission module that wirelessly transmits data when the transmission is permitted, and a power source that supplies power to each module. The signal processor module has a microcomputer and an interval timer that outputs a first timing signal when a count value corresponds to a set value. The microcomputer is activated by the first timing signal and changes the set value in a compare register according to a vehicle operation state.

Abstract: A semiconductor apparatus includes an amplifying unit, a bias controlling unit, an AD converting unit and a controlling unit. The amplifying unit is configured to amplify an input signal to output an amplified signal. The bias controlling unit is configured to generate a bias voltage to be applied to the input signal. The AD converting unit is configured to AD-convert the amplified signal into an output signal. The controlling unit is configured to output a control signal to the bias controlling unit. The controlling unit outputs the control signal when an output value indicated by the output signal is equal to a predetermined value. The bias controlling unit changes the bias voltage in response to the control signal.

Abstract: A semiconductor integrated circuit has: a differential amplifier circuit including a first MOS transistor connected between a first node and a common node and a second MOS transistor connected between a second node and the common node; a first current supply circuit configured to supply current to the first node; and a second current supply circuit configured to supply current to the second node. A current supply ability of the first current supply circuit is variable.

Abstract: A semiconductor device includes a reference voltage generating section configured to generate a first reference voltage and a second reference voltage based on a voltage supplied from an external power supply, and an AD (analog/digital) conversion circuit operating based on the first reference voltage to generate an AD conversion signal corresponding to an output signal supplied from an external device. The second reference voltage is supplied to the external device, and a ratio of the first reference voltage and the second reference voltage is kept to a constant value regardless of a temperature of the semiconductor device.

Abstract: A semiconductor device includes a reference voltage generating section configured to generate a first reference voltage and a second reference voltage based on a voltage supplied from an external power supply; and an AD (analog/digital) conversion circuit operating based on the first reference voltage to generate an AD conversion signal corresponding to an output signal supplied from an external device through AD conversion. The second reference voltage is supplied to the external device, and a ratio of the first reference voltage and the second reference voltage is kept to a constant value regardless of a temperature of the semiconductor device.

Abstract: A variation detection device has a processor, an AD converter converting a signal voltage output from a sensor to generate an AD converted value and outputting the AD converted value to the processor, a temperature sensor detecting a temperature of the sensor, and a memory storing a table which indicates a relationship between temperatures and initial values. When receiving the AD converted value, the processor identifies a temperature of the sensor based on an output of the temperature sensor, reads out an initial value corresponding to the identified temperature from the table, and calculates a variation between the initial value and the AD converted value.

Abstract: A semiconductor apparatus includes an amplifying unit, a bias controlling unit, an AD converting unit and a controlling unit. The amplifying unit is configured to amplify an input signal to output an amplified signal. The bias controlling unit is configured to generate a bias voltage to be applied to the input signal. The AD converting unit is configured to AD-convert the amplified signal into an output signal. The controlling unit is configured to output a control signal to the bias controlling unit. The controlling unit outputs the control signal when an output value indicated by the output signal is equal to a predetermined value. The bias controlling unit changes the bias voltage in response to the control signal.

Abstract: A data communication system includes a plurality of sensor initiators, each of which has first and second antennas; a communication control module and a plurality of sensor communication modules. The communication control module is connected with the plurality of sensor initiators through a LAN and is configured to control the plurality of sensor initiators such that a first electromagnetic wave signal for a command data signal is transmitted through the first antennas. Each of the plurality of sensor communication modules includes at least a sensor and third and fourth antennas.

Abstract: A semiconductor integrated circuit has: a differential amplifier circuit including a first MOS transistor connected between a first node and a common node and a second MOS transistor connected between a second node and the common node; a first current supply circuit configured to supply current to the first node; and a second current supply circuit configured to supply current to the second node. A current supply ability of the first current supply circuit is variable.

Abstract: A data communication device includes a receiving circuit configured to receive a data signal in an active state. An intermittent activation control circuit activates the receiving circuit into the active state in a predetermined time interval. A control unit operates in response to the data signal received by the receiving circuit. Also, the control unit controls the time interval of the intermittent activation control circuit.

Abstract: A transmitter module has a sensor module that includes a plurality of sensors and operates intermittently, a signal processor module that permits transmission of an output of the sensor module to a receiver module at given permission timings, a radio transmission module that wirelessly transmits data when the transmission is permitted, and a power source that supplies power to each module. The signal processor module has a microcomputer and an interval timer that outputs a first timing signal when a count value corresponds to a set value. The microcomputer is activated by the first timing signal and changes the set value in a compare register according to a vehicle operation state.