Multiway switch volume collection system based on AD sampling circuit

Multiway switch volume collection system based on AD sampling circuit, the volume of relating to in the multiway switch acquisition technique. The problem of must select the CPU of many IO mouth or increase IO mouth dilatation drive circuit to lead to that the cost is too high, the interference killing feature is poor at the current multiway switch's of collection circuit is solved. Every button of device is all established ties one resistance and is formed one button branch road, between the analog signal input that all button branch roads all connected in parallel at AD sampling circuit and the ground of power, series connection one resistance between analog signal input and the positive, button S1 steadily decrease to the resistance resistance that SN establishes ties gradually. The method obtains the button resistance value according to the voltage that AD sampling circuit gathered to according to button resistance value and the closed state of button parallel circuit structure determination one or more button. The utility model is suitable for a need to gather the circuit design technique field of multiway switch volume, also be applicable to the transformation that increases the available circuit of switch acquisition quantity to needs.