Earphone key detection device, method and mobile terminal

Abstract

The invention provides an earphone key detection device, comprising a microphone sound track signal line, a field effect transistor and a detection signal line. The microphone sound track signal line can jump from high level to low level; a grid electrode of the NMOS (N-type Metal Oxide Semiconductor) field effect transistor is connected to the microphone sound track signal line and a source electrode of the NMOS field effect transistor is grounded; a drain electrode of the NMOS field effect transistor is connected with a pull-up resistor branch in one hand and the detection signal line in the other hand; and the detection signal line generates an interruption signal when jumping from low level to high level. The invention further discloses an earphone key detection method and a mobile terminal using the earphone key detection device. The earphone key detection device saves CPU (Central Processing Unit) resources and lowers detection cost, development cost and detection time.

Description

technical field [0001] The invention belongs to the technical field of earphones, and in particular relates to an earphone button detection device, method and mobile terminal. Background technique [0002] With the continuous popularization of mobile terminals, users have higher and higher requirements for mobile terminal functions. [0003] The setting of the earphone circuit on the mobile terminal should have the following identification functions: [0004] 1 Headphone insertion detection: detect whether there is a headphone plugged in, so that the system can switch the voice channel; [0005] 2. Headphone button detection: detect whether the button on the headset is pressed, so that the system can answer and hang up the call. [0006] At present, most of the headphone key detections of mobile terminals use the ADC (Analog-to-Digital Conversion) method and poll with the help of a software system, so that the system can answer and hang up the phone. [0007] Such as fig...

AI Technical Summary

Problems solved by technology

[0008] However, the above-mentioned headphone button detection method consumes CPU resources and increases detection costs; the polling frequency must be adjusted during mobile terminal development, which increases development costs; the priority of ADC in the system is relatively low (after the interruption), and the response speed Not as fast as interruption, when the workload of the mobile terminal system is heavy, the response may be slower, thus increasing the detection time

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