Abstract: An object of the present invention is to provide a battery condition monitor that is capable of reducing labor and equipment costs for parameter setting for evaluation of the battery's condition and capable of readily responding to variations due to individual differences among the same model of vehicles.

Abstract: An object of the present invention is to provide a battery condition monitor that is capable of reducing labor and equipment costs for parameter setting for evaluation of the battery's condition and capable of readily responding to variations due to individual differences among the same model of vehicles.

Abstract: According to the charge pump circuit, a constant current charging and discharging circuit using follower circuits is interposed at current paths in charging and discharging a capacitor for stepping up. Transistors of the follower circuits are alternately made ON in accordance with a clock signal inputted from a signal input portion for switching to connect the capacitor for stepping up and restricting a current in cooperation with resistors or the like.

Abstract: A load drive circuit includes a plurality of control sections for drive controlling of a drive switching element while protecting the drive switching element from a predetermined abnormality status, and a current blocking switching element being provided in at least any of a path between the control sections and a power source and a path between the control sections and a ground. When an input to an input circuit is OFF, a current flowing to a gate drive circuit for on/off driving of the drive switching element becomes an OFF state, the driving switching element becomes an OFF state, and the input circuit causes each current blocking switching element to be an OFF state to block dark current.

Abstract: A protection circuit, to be provided for a circuit arrangement having an inductive load and an FET as an N-channel MOS transistor provided upstream of the load with respect to a flow of power current, the FET controlling an energization state of the load, the protection circuit includes a first connection changer interposed on a connection line between a gate of the FET and a gate drive voltage supply source, the first connection changer changing a connection state between a first connection state in which the gate is connected to the gate drive voltage supply and a second connection state in which the gate is connected to a ground.

Abstract: An overcurrent limit circuit including: a main function part which switches a drive current for a predetermined load between ON and OFF by an ON/OFF operation of a power-MOS-FET used as a drive switch, and which drives the power-MOS-FET and protects overcurrent; and a shunt-detection part which divides electric current applied to the drive switch from a power source side and detects the overcurrent, wherein the main function part, in case that the voltage between a drain of the power-MOS-FET and a source thereof is at least less than a predetermined threshold, has a function of limiting the electric current flowing in the power-MOS-FET on the basis of the overcurrent detected by the shunt-detection part.

Abstract: A load drive circuit includes a plurality of control sections for drive controlling of a drive switching element while protecting the drive switching element from a predetermined abnormality status, and a current blocking switching element being provided in at least any of a path between the control sections and a power source and a path between the control sections and a ground. When an input to an input circuit is OFF, a current flowing to a gate drive circuit for on/off driving of the drive switching element becomes an OFF state, the driving switching element becomes an OFF state, and the input circuit causes each current blocking switching element to be an OFF state to block dark current.

Abstract: According to the charge pump circuit, a constant current charging and discharging circuit using follower circuits is interposed at current paths in charging and discharging a capacitor for stepping up. Transistors of the follower circuits are alternately made ON in accordance with a clock signal inputted from a signal input portion for switching to connect the capacitor for stepping up and restricting a current in cooperation with resistors or the like.

Abstract: A protection circuit, to be provided for a circuit arrangement having an inductive load and an FET as an N-channel MOS transistor provided upstream of the load with respect to a flow of power current, the FET controlling an energization state of the load, the protection circuit includes a first connection changer interposed on a connection line between a gate of the FET and a gate drive voltage supply source, the first connection changer changing a connection state between a first connection state in which the gate is connected to the gate drive voltage supply and a second connection state in which the gate is connected to a ground.

Abstract: A vehicle-installed relay box is for installing a relay used for controlling power supply to a load in a vehicle-installed system provided with different specifications, the relay being configured to different specifications using one or more relay elements in combination in accordance with one type of specification selected from among the different specifications of the vehicle-installed system. The vehicle-installed relay box includes: a plurality of terminals; an installation socket configured to install the relay element; and a wiring configured to connect the relay element installed in the installation socket and the terminals. The installation socket is further configured to be installed a different relay element in accordance with the selected type of specification from among the different specifications of the vehicle-installed system.

Abstract: A protection circuit 10 has a diode 31 being connected in parallel to an inductive load 11 and having a forward direction set reverse to the conduction direction of a power supply current and a Zener diode 33 being placed between one terminal of the diode 31 and one terminal of the load 11 corresponding to the terminal of the diode and having a forward direction matched with the conduction direction of the power supply current.

Abstract: A protection circuit 10 has a diode 31 being connected in parallel to an inductive load 11 and having a forward direction set reverse to the conduction direction of a power supply current and a Zener diode 33 being placed between one terminal of the diode 31 and one terminal of the load 11 corresponding to the terminal of the diode and having a forward direction matched with the conduction direction of the power supply current.