|
DS36277 Datasheet, PDF (1/12 Pages) National Semiconductor (TI) – Dominant Mode Multipoint Transceiver | |||
|
July 1998
DS36277
Dominant Mode Multipoint Transceiver
General Description
The DS36277 Dominant Mode Multipoint Transceiver is de-
signed for use on bi-directional differential busses. It is opti-
mal for use on Interfaces that utilize Society of Automotive
Engineers (SAE) J1708 Electrical Standard.
The device is similar to standard TIA/EIA-485 transceivers,
but differs in enabling scheme. The Driverâs Input is normally
externally tied LOW, thus providing only two states: Active
(LOW), or Disabled (OFF). When the driver is active, the
dominant mode is LOW, conversely, when the driver is dis-
abled, the bus is pulled HIGH by external bias resistors.
The receiver provides a FAILSAFE feature that guarantees a
known output state when the Interface is in the following con-
ditions: Floating Line, Idle Line (no active drivers), and Line
Fault Conditions (open or short). The receiver output is
HIGH for the following conditions: Open Inputs, Terminated
Inputs (50â¦), or Shorted Inputs. FAILSAFE is a highly desir-
able feature when the transceivers are used with Asynchro-
nous Controllers such as UARTs.
Features
n FAILSAFE receiver, RO = HIGH for:
â OPEN inputs
â Terminated inputs
â SHORTED inputs
n Optimal for use in SAE J1708 Interfaces
n Compatible with popular interface standards:
â TIA/EIA-485 and TIA/EIA-422-A
â CCITT recommendation V.11
n Bi-directional transceiver
â Designed for multipoint transmission
n Wide bus common mode range
â (â7V to +12V)
n Available in plastic DIP and SOIC packages
Connection and Logic Diagram
Truth Tables
DS011384-1
Order Number DS36277TM or DS36277TN
See NS Package Number M08A or N08E
Driver
Inputs
DE
DI
L
L
L
H
H
X
Outputs
DO/RI
DO /RI
L
H
H
L
Z
Z
Receiver
Inputs
RE
DO/RIâDO /RI
L
⥠0 mV
L
⤠â500 mV
L
SHORTED
L
OPEN
H
X
Output
RO
H
L
H
H
Z
TRI-STATE® is a registered trademark of National Semiconductor Corporation.
© 1999 National Semiconductor Corporation DS011384
www.national.com
|
▷ |