公开(公告)号：US10461521B2

公开(公告)日：2019-10-29

申请号：US15680834

申请日：2017-08-18

Applicant: FUJITSU TEN LIMITED

Inventor： Masayoshi Kume ,  Motoki Komiya

IPC: H02H5/00 ,  H02H5/04 ,  H02H1/00

Abstract: A driving circuit according to an embodiment includes a driving unit, a first temperature detecting unit, an overheat protecting unit, a second temperature detecting unit, and a failure diagnosing unit. The driving unit supplies a driving current to a load based on a control signal input from a controller. The overheat protecting unit blocks supply of the driving current to the load when the level of the signal output from the first temperature detecting unit exceeds a temperature threshold. The failure diagnosing unit blocks supply of the driving current to the load and outputs a signal of a level corresponding to a temperature out of a temperature range detectable by the second temperature detecting unit to the controller when it is determined that the first temperature detecting unit breaks down.

公开(公告)号：US10656115B2

公开(公告)日：2020-05-19

申请号：US15617755

申请日：2017-06-08

Applicant: FUJITSU TEN LIMITED ,  TOYOTA JIDOSHA KABUSHIKI KAISHA

Inventor： Masatoshi Watanabe ,  Shigeto Umeyama ,  Satoshi Noguchi ,  Motoki Komiya ,  Keisuke Kido ,  Hiroto Miura

IPC: G01N27/416 ,  G01N27/406 ,  G01N27/407 ,  G01N27/41 ,  F02D41/14 ,  G01N27/417

Abstract: A controller of an air-fuel-ratio sensor according to an embodiment includes a current supplying unit, a sweep processing unit, and an abnormality detecting unit. The current supplying unit supplies a current to the pump cell through a first terminal connected with the pump cell so as to control the pump cell. The sweep processing unit executes a sweeping process in which a predetermined voltage or a predetermined current is applied to the detection cell through a second terminal connected with the detection cell so as to change a voltage and a current of the detection cell. The abnormality detecting unit detects a short-circuited state between the first terminal and the second terminal on the basis of a fluctuation in a voltage or a current, generated by the sweeping process, of the first terminal.

公开(公告)号：US10316780B2

公开(公告)日：2019-06-11

申请号：US15637464

申请日：2017-06-29

Applicant: FUJITSU TEN LIMITED ,  TOYOTA JIDOSHA KABUSHIKI KAISHA

Inventor： Masatoshi Watanabe ,  Shigeto Umeyama ,  Motoki Komiya ,  Keisuke Kido ,  Chiharu Morisaki ,  Hiroto Miura

IPC: F02D41/14 ,  F01N11/00 ,  G01D3/028 ,  G01D3/08 ,  G01R31/02 ,  F02D41/20

Abstract: A controller of an air-fuel-ratio sensor includes a control unit, a voltage-abnormality detecting unit, and a short-circuit-abnormality detecting unit. The control unit controls a current and a voltage of a gas sensor element through a plurality of terminals connected with the gas sensor element. The voltage-abnormality detecting unit changes, when at least one of voltages of the plurality of terminals is out of a predetermined range, a voltage level of an output voltage. The short-circuit-abnormality detecting unit causes, when the voltage level of the output voltage changes from a first voltage into a second voltage, a control unit to perform for a predetermined time a protective operation that suppresses currents from the control unit to the plurality of terminals, and detects, when the voltage level of the output voltage is the second voltage after the protective operation is released, a short-circuit abnormality.