Electronic module with moisture protection

• US 6,178,075 B1
• Filed: 06/04/1999
• Issued: 01/23/2001
• Est. Priority Date: 06/04/1999
• Status: Expired due to Fees

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Endicott, Mark Andrew Glinka, Merchant, Viren Babubhai, Colarossi, Vincent
• Primary Examiner(s): SHERRY, MICHAEL JUDE
• Application Number:
  US09/325,912
• Time in Patent Office: 599 Days
• Field of Search: 361/104, 361/93.8, 361/78, 361/54, 361/57, 307/10.1
• US Class Current: 361/54
• CPC Class Codes: H02H 5/083 responsive to the entry or leakage of a liquid into an electrical appliance moisture alarm G08B21/20

Abstract

An electronic module comprising a power supply conductor coupled to one or more electromechanical actuators to supply operable power to the electromechanical actuators. The electronic module also includes a moisture sensor positioned to sense moisture intrusion into the module. Further, the electronic module comprises a first transistor responsively coupled to the moisture sensor, the first transistor coupled to draw current from the power supply conductor when the first transistor is in a conductive state. In addition, the electronic module includes a second transistor responsively coupled to the first transistor and in turn controllingly coupled to the first transistor.

Claims

1. An electronic module comprising:

a power supply conductor coupled to one or more electromechanical actuators to supply operable power to said electromechanical actuators;

a moisture sensor positioned to sense moisture intrusion into said module;

a first transistor responsively coupled to said moisture sensor, said first transistor coupled to draw current from said power supply conductor when said first transistor is in a conductive state;

a second transistor responsively coupled to said first transistor and in turn controllingly coupled to said first transistor.

2. An electronic module as recited in claim 1, wherein:

said electronic module includes a circuit board; and

said moisture sensor comprises two conductors spaced apart from one another on said circuit board.

3. An electronic module as recited in claim 2, wherein:

said electronic module includes a housing in which said circuit board is disposed; and

said housing includes an opening disposed adjacent said moisture sensor.

4. An electronic module as recited in claim 1, wherein:

said electronic module includes an overcurrent protection device through which electrical power is supplied to said power supply conductor;

said first transistor has sufficient current conduction capability to cause said overcurrent protection device to open.

5. An electronic module as recited in claim 4, wherein said overcurrent protection device is a fuse.

6. An electronic module as recited in claim 1, wherein said first transistor is a field-effect transistor (FET).

7. An electronic module as recited in claim 6, wherein said FET has a drain terminal coupled via a resistor to said power supply conductor, said FET and said resistor being selected such that when said FET is fully conductive, said FET causes current flow through said overcurrent protection device sufficient to open said overcurrent protection device.

8. An electronic module as recited in claim 7, wherein:

said second transistor is a bipolar transistor;

said bipolar transistor has a base and an emitter which together define a base-emitter junction; and

said resistor is coupled substantially across said base-emitter junction.

9. An electronic module as recited in claim 8, wherein said emitter is coupled to said power supply conductor.

10. An electronic module comprising:

a power supply conductor coupled to one or more electromechanical actuators to supply operable power to said electromechanical actuators;

at least one moisture sensor positioned to sense moisture intrusion into said module;

a field-effect transistor (FET) having a drain terminal coupled to said power supply conductor, and further having a gate terminal; and

a transistor having a control input terminal responsively coupled in electrical communication with said drain terminal and having an output terminal controllingly coupled in electrical communication with said gate terminal.

11. An electronic module as recited in claim 10, wherein:

said power supply conductor is supplied electrical power through an overcurrent protection device;

said coupling of said drain terminal to said power supply terminal is via a resistor; and

said FET and said resistor are selected such than when said FET is fully conductive, it will draw current sufficient to open said overcurrent protection device.

12. An electronic module as recited in claim 11, wherein:

said transistor is a bipolar transistor; and

said resistor is coupled substantially across a base-emitter junction of said transistor.

13. An electronic module as recited in claim 12, wherein said overcurrent protection device is a fuse.

14. An electronic module as recited in claim 10, wherein:

said transistor is a bipolar transistor;

said coupling of said drain terminal to said power supply terminal is via a resistor; and

said resistor is coupled substantially across a base-emitter junction of said transistor.

15. An electronic module as recited in claim 11, wherein said overcurrent protection device is a fuse.