Dual reference capacitive sensing user interface
A module for controlling power supply to a load in a product which includes a microchip, and an electromechanical switch and a proximity/touch sensor connected to the microchip, preferably to the same input. The switch is primarily used to activate or deactivate the load and the proximity/touch sensor to vary the effect of operating the switch, or to control additional functions such as the activation of a signal, typically a light signal, which helps to locate the product, particularly in the dark, and to vary the duration of an automatic time-out period at the end of which the load is deactivated.
1. An electronic switch module for use in a product with an energy consuming load, said module comprising:
a microchip;
at least one capacitive sensor forming part of a user interface;
said capacitive sensor at least partially implemented in said microchip;
wherein the electronic switch module is configured to receive signals through the user interface and to interpret such signals as user interface commands; and
wherein the capacitive sensor is configured to establish a reference level during a touch condition that is used to determine when a no-touch condition happens, and wherein the capacitive sensor establishes a no-touch reference level during a no-touch condition that is used to determine the occurrence of a proximity/touch event.
2. The electronic switch module of claim 1 wherein the operating mode of the product is automatically changed when a no-touch condition is detected.
3. The electronic switch module of claim 1 wherein the product further comprises a DC power source and RF circuitry.
4. The electronic switch module of claim 1 wherein the detection of a no-touch condition by the capacitive sensor is used to prevent specific commands or functions of the product.
5. The electronic switch module of claim 1 wherein the capacitive sensor differentiates between signals indicating a proximity event and a touch event.
6. The electronic switch module of claim 1 wherein the microchip controls a delayed de-activation of a function that was activated in response to an activation command received through said capacitive sensor user interface.
7. A product employing the electronic switch module of claim 1 , said product comprising a casing wherein the electronic switch module, a visible indicator that is activated by the microchip in response to the detection of a proximity event and the load are all attached to or enclosed in said casing.
8. A method of operating a user interface module as part of a product, wherein the user interface module comprises a microchip and at least one capacitive sensor, the method including the steps of:
a) using a capacitive sensing touch reference level, established during a time when a touch condition prevails to determine when a no-touch condition happens; and
b) using a capacitive sensing no-touch reference level established during a time when a no-touch condition prevails to determine when a proximity condition or a touch condition happens.
9. The method of claim 8 further including the step of using the same capacitive sensing module to differentiate between proximity and touch events when the reference level used is the no-touch reference level.
10. The method of claim 8 further including the step of halting some functions of the product when a no-touch condition is detected when the reference level used is the touch reference level.
11. The method of claim 10 further including the step of automatically, upon detecting a proximity event, re-activating a function that was de-activated when a no-touch condition was detected.
12. The method of claim 10 further including the step of automatically, upon detecting a touch event, re-activating a function that was de-activated when a no-touch condition was detected.
13. The method of claim 10 further including the step of halting some functions in a way that the functions cannot be re-activated by some touch events, if a no-touch condition prevailed for at least a predefined minimum period of time.
14. The method of claim 8 further including the step of blocking certain commands to the product when a no-touch condition prevails.
15. The method of claim 8 used in a product that comprises a dc power source and radio frequency circuitry.
16. The method of claim 8 further including the step of activating a delayed switch off product function upon detecting a no-touch condition.
17. The method of claim 8 further including the step of changing the operating mode of the product when a no touch condition is detected.