The ICL3225 and ICL3245 are 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. Targeted applications are PDAs, Palmtops, and notebook and laptop computers where the low operational power consumption and even lower standby power consumption is critical. Efficient on-chip charge pumps coupled with manual and enhanced automatic powerdown functions reduce the standby supply current to a 1µA trickle. Small footprint packaging and the use of small, low value capacitors ensure board space savings. Data rates greater than 1Mbps are ensured at worst case load conditions. The ICL3225 and ICL3245 are fully compatible with 3. 3V only systems, mixed 3. 3V and 5. 0V systems, and 5. 0V only systems. The ICL3245 is a 3-driver, 5-receiver device that provides a complete serial port suitable for laptop or notebook computers. It also includes a noninverting always-active receiver for "wake-up" capability. The ICL3225 and ICL3245 feature an enhanced automatic powerdown function that powers down the on-chip power-supply and driver circuits. Automatic powerdown occurs when all receiver and transmitter inputs detect no signal transitions for a period of 30s. The ICL3225 and ICL3245 automatically power back up whenever they sense a transition on any transmitter or receiver input.