SN65LBC182 Datasheet, PDF (1/15 Pages) Texas Instruments – DIFFERENTIAL BUS TRANSCEIVER

SN65LBC182
SN75LBC182
SLLS500A − MAY 2001 − REVISED MARCH 2005
DIFFERENTIAL BUS TRANSCEIVER
FEATURES
D One-Fourth Unit Load Allows up to 128
Devices on a Bus
D ESD Protection for Bus Terminals:
− ±15-kV Human Body Model
− ±8-kV IEC61000-4-2, Contact Discharge
− ±15-kV IEC61000-4-2, Air-Gap Discharge
D Meets or Exceeds the Requirements of ANSI
Standard TIA/EIA-485-A and ISO 8482: 1987(E)
D Controlled Driver Output-Voltage Slew Rates
Allow Longer Cable Stub Lengths
D Designed for Signaling Rates^† Up to 250-kbps
D Low Disabled Supply Current . . . 250 µA Max
D Thermal Shutdown Protection
D Open-Circuit Fail-Safe Receiver Design
D Receiver Input Hysteresis . . . 70 mV Typ
D Glitch-Free Power-Up and Power-Down
Protection
APPLICATIONS
D Utility Meters
D Industrial Process Control
D Building Automation
DESCRIPTION
The SN65LBC182 and SN75LBC182 are differential
data line transceivers with a high level of ESD protection
in the trade-standard footprint of the SN75176. They are
designed for balanced transmission lines and meet
ANSI standard TIA/EIA-485-A and ISO 8482. The
SN65LBC182 and SN75LBC182 combine a 3-state,
differential line driver and differential input line receiver,
both of which operate from a single 5-V power supply.
The driver and receiver have active-high and active-low
enables, respectively, which can be externally
connected together to function as a direction control.
The driver outputs and the receiver inputs connect
internally to form a differential input/output (I/O) bus port
that is designed to offer minimum loading to the bus.
This port operates over a wide range of common-mode
voltage, making the device suitable for party-line
applications. The device also includes additional
features for party-line data buses in electrically noisy
environment applications such as industrial process
control or power inverters.
The SN75LBC182 and SN65LBC182 bus pins also
exhibit a high input resistance equivalent to one-fourth
unit load allowing connection of up to 128 similar
devices on the bus. The high ESD tolerance protects
the device for cabled connections. (For an even higher
level of protection, see the SN65/75LBC184, literature
number SLLS236.)
The differential driver design incorporates
slew-rate-controlled outputs sufficient to transmit data
up to 250 kbps. Slew-rate control allows longer
unterminated cable runs and longer stub lengths from
the main backbone than possible with uncontrolled
voltage transitions. The receiver design provides a
fail-safe output of a high level when the inputs are left
floating (open circuit). Very low device supply current
can be achieved by disabling the driver and the receiver.
The SN65LBC182 is characterized for operation from
−40°C to 85°C, and the SN75LBC182 is characterized
for operation from 0°C to 70°C.
functional block diagram
3
DE
4
D
RE
2
R
1
6
A
7
B
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.
†The _{signaling rate of a line, is the number of voltage transitions that are made per second expressed in the units bps (bits per second).}
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.
Copyright  2001, Texas Instruments Incorporated
www.ti.com
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