FEATURES
· ESD Protection for RS-232 Bus Pins
– ±15-kV Human-Body Model (HBM)
– ±8-kV IEC 61000-4-2, Contact Discharge
– ±15-kV IEC 61000-4-2, Air-Gap Discharge
· Meet or Exceed the Requirements of
TIA/EIA-232-F and ITU v.28 Standards
· Operate With 3-V to 5.5-V VCC Supply
· Operate up to 1000 kbit/s
· Two Drivers and Two Receivers
· Low Standby Current . . . 1 mA Typ
· External Capacitors . . . 4 ´ 0.1 mF
· Accepts 5-V Logic Input With 3.3-V Supply

APPLICATIONS
· Battery-Powered Systems
· PDAs
· Notebooks
· Laptops
· Palmtop PCs
· Hand-Held Equipment

DESCRIPTION/ORDERING
INFORMATION
The SN65C3223E and SN75C3223E consist of two
line drivers, two line receivers, and a dual
charge-pump circuit with ±15-kV ESD protection pin
to pin (serial-port connection pins, including GND).
These devices meet the requirements of
TIA/EIA-232-F and provide 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. The devices operate at
typical data signaling rates up to 1000 kbit/s.
Flexible control options for power management are available when the serial port is inactive. The
auto-powerdown feature functions when FORCEON is low and FORCEOFF is high. During this mode of
operation, if the devices do not sense a valid RS-232 signal, the driver outputs are disabled. If FORCEOFF is
set low and EN is high, both drivers and receivers are shut off, and the supply current is reduced to 1 mA.
Disconnecting the serial port or turning off the peripheral drivers causes auto-powerdown to occur.
Auto-powerdown can be disabled when FORCEON and FORCEOFF are high. With auto-powerdown enabled,
the devices are activated automatically when a valid signal is applied to any receiver input. The INVALID output
is used to notify the user if an RS-232 signal is present at any receiver input. INVALID is high (valid data) if any
receiver input voltage is greater than 2.7 V or less than –2.7 V, or has been between –0.3 V and 0.3 V for less
than 30 ms. INVALID is low (invalid data) if the receiver input voltage is between –0.3 V and 0.3 V for more than
30 ms. Refer to Figure 4 for receiver input levels.