Title:
LOAD DISCONNECTION DETECTION CIRCUIT
Document Type and Number:
Japanese Patent JP2008011347
Kind Code:
A
Abstract:
To provide a load disconnection detection circuit having a breakdown strength which is equal to or more than a flyback voltage generated to a load.
If an output terminal 11d connected to an electromagnetic coil becomes in a released state, an index voltage output circuit 17 outputs an index voltage VT equal to a voltage VTref of a node N1 from the output terminal 11d. If a current of the electromagnetic coil is shut off, a flyback voltage Vfb generates at the output terminal 11d. A voltage dividing circuit 18 divides the flyback voltage Vfb into 1/m to be outputted to a window comparator. A diode D3 obstructs the flyback voltage Vfb, and a resistor R8 limits a current when the diode D3 is broken down.
Inventors:
KOJIMA AKIO
Application Number:
JP2006181511A
Publication Date:
January 17, 2008
Filing Date:
June 30, 2006
Export Citation:
Assignee:
DENSO CORP
International Classes:
H03K17/00; F02D41/22; F02D45/00; H03K17/08
Domestic Patent References:
| JPS63248969A | 1988-10-17 | |||
| JPH06252721A | 1994-09-09 | |||
| JP2001257573A | 2001-09-21 | |||
| JPH085064A | 1996-01-12 | |||
| JP2002199577A | 2002-07-12 |
Attorney, Agent or Firm:
Tsuyoshi Sato