Touch switch with integral control circuit

• US 7,030,513 B2
• Filed: 12/01/2003
• Issued: 04/18/2006
• Est. Priority Date: 01/19/1999
• Status: Expired due to Term

• Current Assignee: Touchsensor Technologies LLC (Methode Electronics Incorporated)
• Original Assignee: Touchsensor Technologies LLC (Methode Electronics Incorporated)
• Inventors: Caldwell, David W.
• Primary Examiner(s): Deberadinis, Robert L.
• Application Number:
  US10/725,908
• Publication Number:
  US 20040124714A1
• Time in Patent Office: 869 Days
• Field of Search: 307/116, 341/33
• US Class Current: 307/116
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2217/96077 comprising an electrode which is floating

Abstract

A touch switch apparatus for detecting the presence of an object such as a human appendage, the apparatus having a touch pad and a local control circuit connected to the touch pad and to a controlled device. The touch pad preferable includes a first electrode and a second electrode spaced from and surrounding the first electrode. The control circuit is preferably in integrated circuit form. A signal is provided to the touch pad to generate an electric field thereabout. Introduction of a stimulus near the touch pad disturbs the electric field. The control circuit detects the electric field disturbance in and generates a control signal in response.

Claims

1. A panel comprising a plurality of electronic sensor apparatus, each of said sensor apparatus comprising:

a touch pad comprising at least a first electrode; and

a control circuit disposed on an integrated circuit, said control circuit comprising;

a signal source;

an input section comprising a first input channel and a second input channel;

a decision section having a first input, a second input, and an output; and

an output section;

wherein signal source is coupled to said touch pad;

wherein said first input channel is coupled to said signal source, said first electrode and said first input of said decision section;

wherein said second input channel is coupled to said signal source and said second input of said decision section; and

wherein said output of said decision section is coupled to said output section.

2. The panel of claim 1 wherein said output section comprises a latch.

3. The panel of claim 2 wherein said latch is coupled to a controlled device.

4. The panel of claim 1 wherein said output section comprises a drive transistor.

5. The panel of claim 4 wherein said drive transistor is coupled to a controlled device.

6. The panel of claim 1 wherein said output section comprises an output line.

7. The panel of claim 6 wherein said output line is coupled to a controlled device.

8. The panel of claim 1 wherein said signal source is an oscillator.

9. The panel of claim 1 wherein each of said electronic sensor apparatus further comprises a second electrode and said second input channel is further coupled to said second electrode.

10. The panel of claim 9 wherein said output section comprises a latch.

11. The panel of claim 10 wherein said latch is coupled to a controlled device.

12. The panel of claim 9 wherein said output section comprises a drive transistor.

13. The panel of claim 12 wherein said drive transistor is coupled to a controlled device.

14. The panel of claim 9 wherein said output section comprises an output line.

15. The panel of claim 14 wherein said output line is coupled to a controlled device.

16. The panel of claim 9 wherein said signal source is an oscillator.