Abstract: The DC/DC converter is provided with a failure detector that detects a failure in at least one of a first output-side voltage sensor, a second output-side voltage sensor, and an input-side voltage sensor, based on the respective detection values of the input-side voltage sensor, the first output-side voltage sensor, the second output-side voltage sensor, and a DC power source voltage sensor.

Abstract: The DC/DC converter is provided with a failure detector that detects a failure in at least one of a first output-side voltage sensor, a second output-side voltage sensor, and an input-side voltage sensor, based on the respective detection values of the input-side voltage sensor, the first output-side voltage sensor, the second output-side voltage sensor, and a DC power source voltage sensor.

Abstract: A DC/DC converter in which a both-end voltage of each of capacitors can be safely uniformalized while an over current, which is passed through between the capacitors composing the DC/DC converter, is prevented. In a DC/DC converter which includes a plurality of switching elements, a reactor, a low-voltage side capacitor, a high-voltage side capacitor, a charge-discharge capacitor, and a controller which drives and controls the switching elements, the controller performs soft start control in which a duty ratio of at least one of the switching elements is gradually varied from 0% to 100%, and the switching element, in which the soft start control is not performed during the term of the soft start control, is turned off.

Abstract: A DC/DC converter in which a both-end voltage of each of capacitors can be safely uniformalized while an over current, which is passed through between the capacitors composing the DC/DC converter, is prevented. In a DC/DC converter which includes a plurality of switching elements, a reactor, a low-voltage side capacitor, a high-voltage side capacitor, a charge-discharge capacitor, and a controller which drives and controls the switching elements, the controller performs soft start control in which a duty ratio of at least one of the switching elements is gradually varied from 0% to 100%, and the switching element, in which the soft start control is not performed during the term of the soft start control, is turned off.

Abstract: A motor drive control device is provided in which if any abnormality occurs in a drive control circuit, drive command signals the drive control circuit generates are interrupted at once, so that an AC motor can be stopped in safety. A monitor control circuit and drive command signal interruption circuit are provided to the drive control circuit that takes variable-speed control of the AC motor supplied with power from a DC drive power source via a semiconductor bridge circuit. If any abnormality occurs in the drive control circuit, the drive command signals the drive control circuit generates are interrupted at once. When starting operation, the drive control circuit and monitor control circuit cooperate with each other to conduct preliminary check as to whether or not the drive command signal interruption circuit operates normally, base on a predetermined time schedule, and stop the AC motor without fail if any abnormality occurs during operation.

Abstract: A motor drive control device is provided in which if any abnormality occurs in a drive control circuit, drive command signals the drive control circuit generates are interrupted at once, so that an AC motor can be stopped in safety. A monitor control circuit and drive command signal interruption circuit are provided to the drive control circuit that takes variable-speed control of the AC motor supplied with power from a DC drive power source via a semiconductor bridge circuit. If any abnormality occurs in the drive control circuit, the drive command signals the drive control circuit generates are interrupted at once. When starting operation, the drive control circuit and monitor control circuit cooperate with each other to conduct preliminary check as to whether or not the drive command signal interruption circuit operates normally, base on a predetermined time schedule, and stop the AC motor without fail if any abnormality occurs during operation.

Abstract: In an internal-combustion-engine control apparatus provided with an exhaust gas sensor control device that outputs a detection signal detected by an exhaust-gas sensor, while switching amplification factors of an amplification circuit or offset voltages of an offset circuit, it is determined whether the exhaust-gas sensor is in an activation state or not, and an electric current flowing into the exhaust-gas sensor is stopped, in the case where it is determined that the exhaust-gas sensor is in a non-activation state; the amplification factors of the amplification circuit are switched so that there is detected an air-fuel ratio signal at the time when an electric current flowing into the exhaust-gas sensor is stopped, and it is determined whether or not the offset circuit is abnormal, based on whether the respective air-fuel ratio signals at the amplification factors are within a predetermined range.

Abstract: In an exhaust gas sensor control device that outputs a detection signal detected by the exhaust-gas sensor, while switching amplification factors or offset voltages, in the case where an abnormality occurs in an amplification circuit or in an offset circuit, the abnormality is rapidly detected, whereby deterioration in an exhaust gas can be prevented.

Abstract: A failure diagnostic apparatus is provided with an offset power source for offsetting a ground-side voltage of an air-fuel ratio sensor, an activation state judging unit for judging whether the air-fuel ratio sensor is active, a failure diagnosing unit for judging for a failure from an offset-added output signal of the air-fuel ratio sensor in a period when the activation state judging unit judges that the air-fuel ratio sensor is active, an input resistance switching unit for switching the level of an input signal from the air-fuel ratio sensor when the failure diagnosing unit has detected a failure in the air-fuel ratio sensor, and a failure state judging unit for determining a type of failure of the air-fuel ratio sensor on the basis of a voltage level obtained when the input resistance switching unit has switched the input signal level.

Abstract: A control apparatus for an internal combustion engine can control an actual operating characteristic with high precision by shortening a response time thereof. The control apparatus capable of changing an actual phase angle of a camshaft by an OCV includes a crank angle sensor for detecting a crank angle of a crankshaft and generating a crank angle signal, an actual phase angle detection section for detecting the actual phase angle of the camshaft, an air flow sensor and a throttle position sensor for detecting an operating state of the engine, a target phase angle calculation section for calculating a target phase angle based on the operating state, and a phase angle feedback control section for calculating an operation amount to the OCV so as to make the actual phase angle coincide with the target phase angle. The phase angle feedback control section calculates the operation amount in synchronization with the crank angle signal.

Abstract: A control apparatus for an internal combustion engine can control an actual operating characteristic with high precision by shortening a response time thereof. The control apparatus capable of changing an actual phase angle of a camshaft by an OCV includes a crank angle sensor for detecting a crank angle of a crankshaft and generating a crank angle signal, an actual phase angle detection section for detecting the actual phase angle of the camshaft, an air flow sensor and a throttle position sensor for detecting an operating state of the engine, a target phase angle calculation section for calculating a target phase angle based on the operating state, and a phase angle feedback control section for calculating an operation amount to the OCV so as to make the actual phase angle coincide with the target phase angle. The phase angle feedback control section calculates the operation amount in synchronization with the crank angle signal.

Abstract: A failure diagnostic apparatus is provided with an offset power source for offsetting a ground-side voltage of an air-fuel ratio sensor, an activation state judging unit for judging whether the air-fuel ratio sensor is active, a failure diagnosing unit for judging for a failure from an offset-added output signal of the air-fuel ratio sensor in a period when the activation state judging unit judges that the air-fuel ratio sensor is active, an input resistance switching unit for switching the level of an input signal from the air-fuel ratio sensor when the failure diagnosing unit has detected a failure in the air-fuel ratio sensor, and a failure state judging unit for determining a type of failure of the air-fuel ratio sensor on the basis of a voltage level obtained when the input resistance switching unit has switched the input signal level.

Abstract: Air-fuel ratio control apparatus for an engine of automobile for controlling an air-fuel ratio to a desired value includes module (33) for computing a purge ratio (Pr) from a purge quantity (QPRG) and an engine operation state, module (35) for computing a purge air concentration (Pn) from the purge ratio (Pr) and an air-fuel ratio feedback correcting coefficient (CFB), module (36) for computing a purge air concentration correcting coefficient (CPRG) from the purge ratio and the purge air concentration, module (39) for computing a fuel injection quantity (Qf) supplied to the engine (6) from the purge air concentration correcting coefficient, and module (37) for detecting an accelerating state of the automobile. The purge air concentration correcting coefficient is reset to an initial value when the purge air concentration correcting coefficient is not greater than a predetermined value (indicating leanness) and when the acceleration is detected.

Abstract: Air-fuel ratio control apparatus for an engine of automobile for controlling an air-fuel ratio to a desired value includes module (33) for computing a purge ratio (Pr) from a purge quantity (QPRG) and an engine operation state, module (35) for computing a purge air concentration (Pn) from the purge ratio (Pr) and an air-fuel ratio feedback correcting coefficient (CFB), module (36) for computing a purge air concentration correcting coefficient (CPRG) from the purge ratio and the purge air concentration, module (39) for computing a fuel injection quantity (Qf) supplied to the engine (6) from the purge air concentration correcting coefficient, and module (37) for detecting an accelerating state of the automobile. The purge air concentration correcting coefficient is reset to an initial value when the purge air concentration correcting coefficient is not greater than a predetermined value (indicating leanness) and when the acceleration is detected.