NONPOLAR RS485 CIRCUIT FOR REALIZING POLARITY REVERSAL

摘要

The present invention relates to a nonpolar RS485 circuit for realizing polarity reversal, comprising: an A/B comparison module, an oscillator, a timer, an XNOR gate and an RS485 interface circuit, wherein the A/B comparison module comprises a first PMOS transistor, a second PMOS transistor, a third PMOS transistor, a first resistor, a second resistor, a first triode, a second triode and a comparator. By means of the nonpolar RS485 circuit for realizing polarity reversal, four MOS switches in a traditional scheme are removed by using a new logical structure to replace the MOS switches so as to switch the polarity of a circuit, and the polarity is switched by carrying out XNOR processing on an output signal OUT2 of an A/B comparison module and an interrupt signal EN generated by a timer. In this way, the influence of MOS switches can be eliminated, the polarity (data) reversal threshold value consistency of different circuits and the parameter consistency of a single circuit before and after polarity reversal are improved, and the yield of the circuits is improved. The invention has a wide range of application.