2.5V, ±15kV ESD-Protected RS-232 Transceivers for PDAs and Cell Phones

The MAX3388E/MAX3389E are 2.5V-powered EIA/TIA-232 and V.28/V.24 communications interfaces with low power requirements, high data-rate capabilities, and enhanced electrostatic discharge (ESD) protection. The MAX3388E/MAX3389E have two receivers and three transmitters. All RS-232 inputs and outputs are protected to ±15kV using the IEC 1000-4-2 Air-Gap Discharge method, ±8kV using the IEC 1000-4-2 Contact Discharge method, and ±15kV using the Human Body Model.

In addition to the traditional RS-232 I/O, these devices have dedicated logic-level I/O pins for additional device-to-device handshaking. During shutdown the logic-level I/O pins are active for the MAX3389E. An internal 62Ω switch is provided to switch power to external circuitry or modules.

A proprietary low-dropout transmitter output stage enables RS-232 compatible performance from a +2.35V to +3.0V supply with a dual charge pump. The charge pump requires only four small 0.1µF capacitors for operation from a +2.5V supply. The MAX3388E/MAX3389E are capable of running at data rates up to 460kbps while maintaining RS-232-compatible output levels.

The MAX3388E/MAX3389E have a unique VL pin that allows interoperation in mixed-logic voltage systems. Both input and output logic levels are pin programmable through the VL pin. The MAX3388E/MAX3389E are available in a space-saving TSSOP package.

Applications

* Battery-Powered Applications * Cellular Data Cables * Handheld Equipment * PDAs and PDA Cradles * Peripherals * Subnotebook and Palmtop Computers

* VL Pin for Compatibility with Mixed-Voltage Systems

* Additional I/O for Hot-Sync Applications

* ±15kV ESD Protection on Rx Inputs, Tx Outputs, LIN, and SWIN

* Low 300µA Supply Current

* Guaranteed 460kbps Data Rate

* 1µA Low-Power Shutdown

* Integrated Switch for Powering Remote Circuitry

* Flow-Through Pinout

* LOUT Active During Shutdown (MAX3389E)