MAX3221IDBR

The MAX3221 device consists of one line driver, one
line receiver with dedicated enable pin, and a dual
charge-pump circuit with ±15-kV ESD protection pin
to pin (serial-port connection pins, including GND).
The device meets the requirements of TIA/EIA-232-
F and provides the electrical interface between
an asynchronous communication controller and the
serial-port connector. The charge pump and four small
external capacitors allow operation from a single
3-V to 5.5-V supply. These devices operate at data
signaling rates up to 250 kbps and a maximum of
30-V/μs driver output slew rate.
Flexible control options for power management
are available when the serial port is inactive.
The automatic power-down feature functions when
FORCEON is low and FORCEOFF is high. During
this mode of operation, if the device does not sense a
valid
RS-232 signal on the receiver input, the driver output
is disabled and the supply current is reduced to 1 μA.
The INVALID output notifies the user if an RS-232
signal is present at the receiver input.