Initializing a capacitive sensing switch for a wireless device

摘要

An apparatus, system, and method that initialize a capacitive sensing switch and detects a pushed button are described. The apparatus comprises a keypad, a logic component, an initialization threshold, a measured capacitive value, and a processor. The keypad comprises at least one capacitive sensing switch. The logic component is configured to determine a capacitive sensing range for each capacitive sensing switch, wherein the range corresponds to the difference between the maximum and minimum capacitance. Each capacitive sensing switch is initialized when the capacitive sensing range exceeds the initialization threshold. The measured capacitive value measures the capacitive value for each switch and a corresponding push-button threshold determines whether the button has been pushed. The processor is configured to process computer instructions that correspond to each switch when the capacitive sensing range exceeds the initialization threshold and when the measured capacitive value for each capacitive sensing switch exceeds the push-button threshold.

主权项

1. An apparatus for initializing a capacitive sensing switch and detecting a pushed button, the apparatus comprising:
a keypad associated with a wireless device, wherein the keypad comprises a plurality of capacitive sensing switches; a logic component determines a capacitive sensing range for each capacitive sensing switch of the plurality of capacitive sensing switches, wherein the capacitive sensing range corresponds to a difference between a maximum capacitance and a minimum capacitance, wherein the minimum capacitance and the maximum capacitance are measured by calculating a RC time constant; an initialization threshold associated with the capacitive sensing range, wherein the logic component determines whether the capacitive sensing range exceeds the initialization threshold, wherein said each capacitive sensing switch is initialized when the capacitive sensing range exceeds the initialization threshold; a corresponding measured capacitive value that measures a corresponding capacitive value for said each capacitive sensing switch is associated with a corresponding push-button threshold that determines whether a corresponding button has been pushed; and a processor processes computer instructions that correspond to said each capacitive sensing switch when the capacitive sensing range exceeds the initialization threshold and when the corresponding measured capacitive value for said each capacitive sensing switch exceeds the corresponding push-button threshold.