A direct drive circuit and method for plugging and unplugging detection of audio wires

Abstract

Direct drive circuitry and a method for the hot plug detection of an audio line end. The circuitry includes an audio line end jack, a pull-up circuit, a pull-down circuit and an operational amplifier. Two ends of the audio line end jack are connected to the pull-up circuit and pull-down circuit respectively, the positive input end of the operational amplifier inputs a reference voltage, the negative input end and output end of the operational amplifier are connected to two ground ends of the audio line end jack respectively, and by detecting the voltage at the negative input end of the operational amplifier, the hot plug state of the audio line end is determined according to the detected voltage . The direct drive circuitry for the hot plug detection of an audio line end is simple and reliable without occupying an additional GPIO port to perform detection, saving Pin resources; moreover, whether or not the operational amplifier is opened will not affect the accuracy of the detection result, which can reduce power consumption and at the same time reduce the number of elements used by the direct drive circuitry for detection, saving the area of the printed circuit board (PCB) and lowering the cost.

Description

technical field [0001] The invention relates to detection technology, in particular to a direct drive circuit and method for plugging and unplugging detection of audio cable ends. Background technique [0002] In the application field of electronic equipment, it is often necessary to detect the insertion and removal of audio cables, and report the detection results to the control circuit of the terminal product for the next step. [0003] figure 1 It is a schematic diagram of a commonly used direct-drive circuit for plugging and unplugging detection of audio cables. The direct-drive circuit is widely used because it omits the DC blocking capacitor of the audio cable. Its function is that the node VRO provides the same DC voltage as the output terminals OL and OR of the audio cable socket. . Such as figure 1 As shown, the connection end of the audio cable head includes the left channel L end, the right channel R end and the grounding terminal GND, the connection end of the...

AI Technical Summary

Problems solved by technology

[0006] The present invention provides a direct drive circuit and method for plugging and unplugging detection of audio plugs, which are used to solve the problems in the prior art that an additional GPIO port needs to be occupied to detect plugging and unplugging of audio plugs, and the operational amplifier needs to be continuously turned on

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