The PD4726 is a high-voltage silicon gate CMOS line driver/receiver conforming to EIA/TIA-232-E Standards. It contains a DC/DC converter and can operate with a +5 V single power supply. In addition, it is also provided with ancillary functions such as a standby function. This IC is equipped with four driver circuits and seven receiver circuits and can configure a simple RS-232 interface circuit with only four external capacitors.