The invention discloses a signal conversion device; a voice frequency signal sent by an intelligent mobile device is sampled, decoded and converted into an infrared signal, and the signal conversion device is composed of three parts: an intelligent device interface part, a voice frequency signal sampling sorting circuit and an infrared emission head. With utilization of editability of the voice frequency signal and the multi-functional characteristic and controllability of the intelligent mobile device, the signal conversion device has versatility of editable signal and controllable multiple application programs, has no need of changing intelligent mobile device hardware, also can realize the plug-and-play effect, is convenient and quick, and can be applied in the fields of consumer electronic products and intelligent furniture.