The MAX3318 is a dual-driver, dual-receiver, RS-232 compatible transceiver. The device features auto-power-down plus and enhanced electrostatic discharge (ESD) protection integrated into the chip. Driver output and receiver input are protected to ±8 kV using the IEC 61000 Air-Gap Discharge method, ±8 kV using the IEC 61000 Contact Discharge method, and ±15 kV using the Human-Body Model (HBM).

The device operates at a data rate of 460 kbps. The transceiver has a proprietary low-dropout driver output stage enabling RS-232-compatible operation from a 2.25-V to 3-V supply with a dual charge pump. The charge pump requires only four 0.1-μF capacitors and features a logic-level output (READY) that asserts when the charge pump is regulating and the device is ready to begin transmitting.

The MAX3318 achieves a 1-μA supply current using the auto-power-down feature. This device automatically enters a low-power power-down mode when the RS-232 cable is disconnected or the drivers of the connected peripherals are inactive for more than 30 s. The device turns on again when it senses a valid transition at any driver or receiver input. Auto power down saves power without changes to the existing BIOS or operating system.

This device is available in two space-saving packages: 20-pin SSOP and 20-pin TSSOP.