Patent attributes
This invention provides an electronic control unit is capable of suppressing electromagnetic noise having a frequency band used in a portable wireless apparatus, and capable of exhibiting a noise resistance property against electromagnetic noise. The electronic control unit including a constant voltage power supply circuit portion, an analog signal inputting circuit portion, and a conversion processing circuit portion, an analog sensor and a driving power supply being connected to the outside, and the unit being connected to the analog sensor through a power supply line and a signal line, in which the analog signal inputting circuit portion includes a current limiting circuit portion, an integrating circuit portion, a current limiting resistor, a signal noise absorbing circuit, and a first bypass capacitor, and capacitance (C1) and parasitic inductance (L1) of the first bypass capacitor are set in a range of 7×106<1/[2π√(L1×C1)]<35×106.