ICL3221E RS-232 Interface ICs Renesas Electronics ICL3221E RS-232 Interface ICs is 3.0V to 5.5V powered RS-232 transmitters/receivers that meet ElA/TIA-232 and V.28/V.24 specifications, even at VCC=3.0V. Additionally, the devices provide ±15kV ESD protection (IEC61000-4-2 Air Gap and Human Body Model) on transmitter outputs and receiver inputs (RS-232 pins).