Abstract: A load driving device includes a synchronous rectifier circuit having a driving-side switching element and a reflux-side switching element; a driver control circuit controls the synchronous rectifier circuit; and a voltage monitor circuit that monitors whether the voltage of an output terminal of the synchronous rectifier circuit is within a predetermined voltage range; where the driver control circuit, upon receiving a diagnosis command, performs control so that when the driving-side switching element is switched from ON to OFF, the reflux-Side switching element is also switched to OFF; and the voltage monitor circuit detects a normal state when the voltage to be monitored is within a normal level during a period in which both the driving-side switching element and the reflux-side switching element are turned OFF.

Abstract: Provided is an electronic control unit capable of performing a high-accurate failure diagnosis in a short time as an electronic control unit having a failure diagnosis function. A load drive circuit that drives a load, a control circuit that controls the load drive circuit, and a diagnosis circuit that diagnoses an output state of the load drive circuit and outputs a diagnostic result to the control circuit are provided. The diagnosis circuit outputs a diagnosis completion flag indicating whether or not there is a diagnosis opportunity to the control circuit.

Abstract: Provided is an electronic control device including a timer that operates during a key-off time period, the electronic control device having high reliability to diagnose whether the timer is normally operated even during the key-off time period. The electronic control device includes a first power supply unit to which a battery voltage is always supplied as a power supply voltage, the first power supply unit including a first timer that measures a key-off time period, a diagnostic timer different from the first timer, and a first timer diagnosis unit that compares a timer value of the first timer with that of the diagnostic timer during the key-off time period.

Abstract: Provided is a highly versatile and reliable power supply device (power supply ASIC) that can support electronic devices with a wide range of drive currents while suppressing a cost increase, and an electronic control device using the same. An electronic control device includes: a first power supply circuit that outputs a first voltage; a second power supply circuit that generates a second voltage from the first voltage; and a first MOSFET arranged independently of the first power supply circuit and the second power supply circuit. The second power supply circuit includes: a reference power supply that outputs a reference voltage; an amplifier that amplifies the reference voltage; a second MOSFET connected in parallel with the first MOSFET; a voltage detection unit that detects a voltage value of a gate terminal of the first MOSFET; and a switching unit that connects an output from the amplifier to either the gate terminal of the first MOSFET or a gate terminal of the second MOSFET.

Abstract: Provided is an electronic control unit capable of performing a high-accurate failure diagnosis in a short time as an electronic control unit having a failure diagnosis function. A load drive circuit that drives a load, a control circuit that controls the load drive circuit, and a diagnosis circuit that diagnoses an output state of the load drive circuit and outputs a diagnostic result to the control circuit are provided. The diagnosis circuit outputs a diagnosis completion flag indicating whether or not there is a diagnosis opportunity to the control circuit.

Abstract: The conventional method requires at least one cycle of diagnostic time for pulse detection, which causes a problem of longer diagnostic time. A load driving device of the present invention includes a synchronous rectifier circuit having a driving-side switching element and a reflux-side switching element; a driver control circuit controls the synchronous rectifier circuit; and a voltage monitor circuit that monitors whether the voltage of an output terminal of the synchronous rectifier circuit is within a predetermined voltage range; where the driver control circuit, upon receiving a diagnosis command, performs control so that when the driving-side switching element is switched from ON to OFF, the reflux-side switching element is also switched to OFF; and the voltage monitor circuit detects a normal state when the voltage to be monitored is within a normal level during a period in which both the driving-side switching element and the reflux-side switching element are turned OFF.

Abstract: In a power supply circuit in which a power supply sequence is variable, a malfunction of a device to which power is supplied caused by a wrong power-on order is prevented. In a power supply circuit according to the present invention, an operation state of a previous voltage regulator is detected, and based on a detection result, an order of activation or stop of respective voltage regulators is controlled.

Abstract: In a power supply circuit in which a power supply sequence is variable, a malfunction of a device to which power is supplied caused by a wrong power-on order is prevented. In a power supply circuit according to the present invention, an operation state of a previous voltage regulator is detected, and based on a detection result, an order of activation or stop of respective voltage regulators is controlled.