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Operate With 3-V to 5.5-V VCC Supply
Operate Up To 1 Mbit/s
Low Standby Current . . . 1 μA Typ
External Capacitors . . . 4 × 0.1 μF
Accept 5-V Logic Input With 3.3-V Supply
Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
RS-232 Bus-Pin ESD Protection Exceeds
±15 kV Using Human-Body Model (HBM)
Applications
− Battery-Powered Systems, PDAs,
Notebooks, Laptops, Palmtop PCs, and
Hand-Held Equipment
description/ordering information
The SN65C3223 and SN75C3223 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). The devices 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 data signaling rates up to 1 Mbit/s and a driver output slew rate of 24 V/μs to 150 V/μs
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 device does 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 μA.
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 device is 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 μs. INVALID is low (invalid data) if the receiver input voltage is between −0.3 V and 0.3 V for more than
30 μs. Refer to Figure 4 for receiver input levels.
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