Invention Grant
- Patent Title: Load driving and diagnosis system and control method
- Patent Title (中): 负载驾驶和诊断系统及控制方法
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Application No.: US12336941Application Date: 2008-12-17
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Publication No.: US08045311B2Publication Date: 2011-10-25
- Inventor: Mitsuhiko Watanabe , Chihiro Sato , Ryoichi Oura , Hirofumi Kurimoto , Koichi Ono
- Applicant: Mitsuhiko Watanabe , Chihiro Sato , Ryoichi Oura , Hirofumi Kurimoto , Koichi Ono
- Applicant Address: JP Tokyo
- Assignee: Hitachi, Ltd.
- Current Assignee: Hitachi, Ltd.
- Current Assignee Address: JP Tokyo
- Agency: Crowell & Moring LLP
- Priority: JP2008-002134 20080109
- Main IPC: H02H3/20
- IPC: H02H3/20

Abstract:
A load driving and diagnosis system controls the feed and block of a load current flowing into an inductor such as a solenoid. The load driving and diagnosis system holds a counter-electromotive force, which is developed when the load current is blocked, at a voltage higher than a supply voltage so that the load current will decay for a short time. When an overcurrent condition is established in the load driving and diagnosis system because of a short circuit to a power supply, a malfunction of a circuit or destruction thereof may take place. In addition to a voltage holding means that holds a switching circuit output voltage at a predetermined voltage, a voltage holding means having a different predetermined voltage set therein is included. Moreover, a selection switch that switches the predetermined voltages according to a detected overcurrent condition is included.
Public/Granted literature
- US20090174980A1 Load Driving and Diagnosis System and Control Method Public/Granted day:2009-07-09
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