SP3232E串口电路，有需要的朋友下来看看。

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SP3222E3232E True 30V to 55V RS232 Transceivers FEATURES Meets true EIATIA232F Standards from a 30V to 55V power supply Minimum 120Kbps Data Rate Under Full Load 1A LowPower Shutdown with Receivers Active SP3222E Interoperable with RS232 down to 27V power source Enhanced ESD Specifications 15kV Human Body Model 15kV IEC100042 Air Discharge 8kV IEC100042 Contact Discharge EN C1 V C1 C2 C2 V T2OUT R2IN 1 2 3 4 5 6 7 8 9 18 17 16 15 14 13 12 11 10 SHDN VCC GND T1OUT R1IN R1OUT T1IN T......