The ISL3232E, ISL4221E, and ISL4223E devices are 2. 7V to 5. 5V powered RS-232 transmitters/receivers that meet ElA/TIA-232 and V. 28/V. 24 specifications, even at VCC = 3. 0V. They provide ±15kV ESD protection (IEC61000-4-2 Air Gap and Human Body Model) on transmitter outputs and receiver inputs (RS-232 pins). Targeted applications are PDAs, Palmtops, and hand-held products where the low operational power consumption and even lower standby power consumption are critical. Efficient on-chip charge pumps, coupled with manual and automatic powerdown functions, reduce the standby supply current to a 150nA trickle. The 5mmx5mm Quad Flat No-Lead (QFN) packaging and the use of small, low value capacitors ensure board space savings. Data rates greater than 250kbps are ensured at worst case load conditions. The ISL4221E is a 1 driver, 1 receiver device and the ISL3232E and ISL4223E are 2 driver, 2 receiver devices that, coupled with the 5mmx5mm QFN package, provide the industry's smallest, lowest power serial port suitable for PDAs, and hand-held applications. The 5mmx5mm QFN requires 40% less board area than a 20 Ld TSSOP, and is nearly 20% thinner. The ISL4221E and ISL4223E versions feature an automatic powerdown function that powers down the on-chip power supply and driver circuits. Automatic powerdown occurs when an attached peripheral device is shut off or the RS-232 cable is removed, and conserves system power automatically without changes to the hardware or operating system. The ISL4221E and ISL4223E power back up automatically when a valid RS-232 voltage is applied to any receiver input.
Schematic symbols, PCB footprints, and 3D CAD models from SamacSys can be found by clicking on products in the Product Options table. If a symbol or model isn't available, it can be requested directly from the website.