Renesas Electronics Corporation

Masumi Kon

Jou Kudou

To suppress detection accuracy of a measurement resistance from decreasing by an on-resistance of a selector switch. The selector switch is provided between a first node coupled to a first voltage through a reference resistance and multiple second nodes coupled to the second voltage through measurement resistances, and selects the second node to be coupled to the first node with the selector switch. A correction circuit generates a voltage obtained by adding the second voltage to a voltage between the second node and the first node as a correction voltage. A double integral ADC finds a first integral time elapsed when a difference voltage of the correction voltage to a voltage of the first node is integrated to the first voltage and a second integral time elapsed when the difference voltage of the first voltage to the voltage of the first node is integrated to the correction voltage.

Semiconductor device and electronic control device

A low power consumption DA converter includes a segment type DA converter and an R-2R resistance ladder DA converter. The segment type DA converter is coupled to a power source voltage VDD and outputs a current signal changing in a stepwise manner according to inputted upper bits D[7 to 5]. The R-2R resistance ladder DA converter is coupled to the segment type DA converter in series between the power source voltage VDD and a ground voltage GND, and outputs an output voltage Vout changing in a stepwise manner. The R-2R resistance ladder DA converter changes the output voltage Vout by raising or lowering a reference voltage Vref according to the lower bits D[4 to 0] and the current signal from the segment type DA converter.

Growing community of inventors

Kanagawa, Japan

Masumi Kon