Voltage and current type analog quantity automatic switching acquisition circuit

A voltage/current type analog quantity automatic switching acquisition circuit relates to the technical field of rail transit signal acquisition, is used for a locomotive system, the locomotive system comprises a locomotive recorder, the locomotive system is provided with an acquisition chip MCU corresponding to the locomotive recorder, and the acquisition chip MCU is provided with an I/O pin, and is characterized in that the locomotive system is provided with an analog input INP, an analog input INI and an analog input INN; the automatic switching acquisition circuit is set as a voltage type analog quantity acquisition module, an analog input INP, an analog input INI and an analog input INN are respectively connected with the voltage type analog quantity acquisition module, and when the analog input INI and the analog input INN are connected, the voltage type analog quantity acquisition module can realize current type analog quantity acquisition. According to the utility model, the acquisition of two signals