The MAX3221 device includes a line driver, a line receiver with a dedicated enable pin, and a dual charge-pump circuit with pin-for-pin (serial port connection pins, including GND) ±15kV ESD protection. The device is TIA/EIA-232-F compliant and provides an electrical interface between an asynchronous communications controller and a serial port connector. A charge pump and four small external capacitors support operation from a single 3V to 5.5V supply. The devices operate at data signaling rates up to 250kbps and driver output slew rates of 30V/µs maximum.

Flexible power management control options are provided when the serial port is inactive. When FORCEON is low and FORCEOFF is high, the automatic power-off function is enabled. In this mode of operation, if the device does not sense a valid RS-232 signal at the receiver input, the driver output is disabled and the supply current is reduced to 1 µA. The INVALID output notifies the user of the presence of an RS-232 signal at the receiver input.

Product Features:

RS-232 Bus Pin ESD Protection >±15kV Using Human Body Model (HBM)

Meets or exceeds the requirements of TIA/EIA-232-F and ITU V.28 standards

Operates from 3V to 5.5V VCC Supply

Operates at up to 250kbps

a driver and a receiver

Low Standby Current: 1 µA (Typical)

External Capacitors: 4 × 0.1µF

Accepts 5V logic input and 3.3V supply

Alternative high-speed pin-compatible device (1Mbps)

Auto power-off feature automatically disables drives to save energy