MAX232: May we have USB to RS232 IC?(like FT232R)

Hi Chen,

Something like TUSB3410 could accomplish this function - have you considered that device? Similar to FT232, it would need to be paired with an RS-232 transceiver. You can choose a transceiver device here based on number of channels needed, supply voltage, and ESD rating here:

http://www.ti.com/rs232

Please let us know if you have any questions.

Best regards,
Max