Ep1c6t144c8的io口最高能承受多高电压：

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Ep1c6t144c8的io口最高能承受多高电压： 

最近做一个项目，设计的核心板上用到ep1c6t144c8，485通信接口芯片sn75176，铁电存储器fm31256等，ep1c6t144c8的vccio用3.3v电压，sn75176和fm31256的电源都用5v电压。  问题是，ep1c6t144c8的io口与sn75176、fm31256的输入或输出口连接时，因为用3千欧电阻加5v电压上拉，所以要考虑ep1c6t144c8的io口最高能承受多大电压，能否承受5v电压？承受的电压范围是几伏到几伏（推荐值）？

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Check out Cyclone Device Handbook Page11-3. There you'll find the pullup resistor value and an additional series resistor necessary to work with a 5V input. 

    --- Quote Start ---  Ep1c6t144c8的io口最高能承受多高电压:  最近做一个项目,设计的核心板上用到ep1c6t144c8,485通信接口芯片sn75176,铁电存储器fm31256等,ep1c6t144c8的vccio用3.3v电压,sn75176和fm31256的电源都用5v电压。  问题是,ep1c6t144c8的io口与sn75176、fm31256的输入或输出口连接时,因为用3千欧电阻加5v电压上拉,所以要考虑ep1c6t144c8的io口最高能承受多大电压,能否承受5v电压?承受的电压范围是几伏到几伏(推荐值)?  --- Quote End ---  

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Thank you very much!