SN65C3243, SN75C3243
3-V TO 5.5-V MULTICHANNEL COMPATIBLE RS-232 LINE DRIVERS/RECEIVERS
SLLS353C – JUNE 1999 – REVISED MARCH 2002
D
D
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D
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DB, DW, OR PW PACKAGE
(TOP VIEW)
Operate With 3-V to 5.5-V VCC Supply
Always-Active Noninverting Receiver
Output (ROUT2B)
Low Standby Current . . . 1 µA Typical
External Capacitors . . . 4 × 0.1 µF
Accept 5-V Logic Input With 3.3-V Supply
Inter-Operable With SN65C3238,
SN75C3238
Support Operation From 250 kbit/s to
1 Mbit/s
RS-232 Bus-Pin ESD Protection Exceeds
±15-kV Using Human-Body Model (HBM)
Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
Applications
– Battery-Powered Systems, PDAs,
Notebooks, Laptops, Palmtop PCs, and
Hand-Held Equipment
Package Options Include Plastic
Small-Outline (DW), Shrink Small-Outline
(DB), and Thin Shrink Small-Outline (PW)
Packages
C2+
C2–
V–
RIN1
RIN2
RIN3
RIN4
RIN5
DOUT1
DOUT2
DOUT3
DIN3
DIN2
DIN1
1
28
2
27
3
26
4
25
5
24
6
23
7
22
8
21
9
20
10
19
11
18
12
17
13
16
14
15
C1+
V+
VCC
GND
C1–
FORCEON
FORCEOFF
INVALID
ROUT2B
ROUT1
ROUT2
ROUT3
ROUT4
ROUT5
description
The SN65C3243 and SN75C3243 consist of three line drivers, five line receivers, and a dual charge-pump
circuit with ±15-kV 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. In addition, these devices include an always-active noninverting output (ROUT2B), which allows
applications using the ring indicator to transmit data while the devices are powered down. The devices operate
at data signaling rates up to 1 Mbit/s, and an increased slew-rate range 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, the driver outputs are disabled. If FORCEOFF is
set low, both drivers and receivers (except ROUT2B) 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, and should be done when driving
a serial mouse. 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 all receiver input
voltages are between –0.3 V and 0.3 V for more than 30 µs. Refer to Figure 5 for receiver input levels.
The SN65C3243 is characterized for operation from –40°C to 85°C. The SN75C3243 is characterized for
operation from 0°C to 70°C.
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.
Copyright 2002, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
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