SN65C3221E, SN75C3221E
3-V TO 5.5-V SINGLE-CHANNEL RS-232 1-Mbit/s LINE DRIVER/RECEIVER
WITH ±15-kV IEC ESD PROTECTION
www.ti.com
SLLS694A–NOVEMBER 2005–REVISED DECEMBER 2005
FEATURES
DB OR PW PACKAGE
•
ESD Protection for RS-232 Pins
(TOP VIEW)
– ±15-kV Human-Body Model (HBM)
– ±8-kV IEC 61000-4-2 Contact Discharge
– ±15-kV IEC 61000-4-2 Air-Gap Discharge
Operate With 3-V to 5.5-V VCC Supply
Operate up to 1 Mbit/s
EN
C1+
V+
FORCEOFF
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
CC
GND
•
•
•
•
•
•
C1−
C2+
C2−
V−
DOUT
FORCEON
DIN
Low Standby Current . . . 1 µA Typ
External Capacitors . . . 4 × 0.1 µF
Accepts 5-V Logic Input With 3.3-V Supply
INVALID
ROUT
RIN
RS-232 Bus-Pin ESD Protection Exceeds ±15
kV Using Human-Body Model (HBM)
•
Auto-Powerdown Feature Automatically
Disables Drivers for Power Savings
APPLICATIONS
•
Battery-Powered, Hand-Held, and Portable
Equipment
•
•
•
•
PDAs and Palmtop PCs
Notebooks, Sub-Notebooks, and Laptops
Digital Cameras
Mobile Phones and Wireless Devices
DESCRIPTION/ORDERING INFORMATION
The SN65C3221E and SN75C3221E consist of one line driver, one line receiver, and a dual charge-pump circuit
with ±15-kV IEC ESD protection pin to pin (serial-port connection pins, including GND). These 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. These 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 devices do not sense a valid RS-232 signal on the receiver input, the driver output is disabled. If
FORCEOFF is set low and EN is high, both the driver and receiver are shut off, and the supply current is
reduced to 1 µA. Disconnecting the serial port or turning off the peripheral drivers causes the auto-powerdown
condition 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 the receiver
input. The INVALID output notifies the user if an RS-232 signal is present at the receiver input. INVALID is high
(valid data) if the 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. See Figure 5 for receiver input levels.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Copyright © 2005, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.