DS485_15 Datasheet, PDF (1/16 Pages) Texas Instruments – Low Power RS-485/RS-422 Multipoint Transceiver

DS485
www.ti.com
SNLS122C – JULY 1998 – REVISED APRIL 2013
DS485 Low Power RS-485/RS-422 Multipoint Transceiver
Check for Samples: DS485
FEATURES
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• Meets TIA/EIA RS-485 Multipoint Standard
• ensured Full Load Output Voltage (V _OD3)
• Low Quiescent Current: 200 μA typ
• −7V to +12V Common-Mode Input Voltage
Range
• TRI-STATE Outputs on Driver and Receiver
• AC Performance:
– Driver Transition Time: 25 ns typ
– Driver Propagation Delay: 40 ns typ
– Driver Skew: 1 ns typ
– Receiver Propagation Delay: 200 ns typ
– Receiver Skew: 20 ns typ
• Half-Duplex Flow Through Pinout
• Operates From a Single 5V Supply
• Allows Up To 32 Transceivers on the Bus
• Current-Limiting and Thermal Shutdown For
Driver Overload Protection
• Industrial Temperature Range Operation
• Pin and Functional Compatible With MAX485
and LTC485
DESCRIPTION
The DS485 is a low-power transceiver for RS-485
and RS-422 communication. The device contains one
driver and one receiver. The drivers slew rate allows
for operation up to 2.5 Mbps (see Applications
Information section).
The transceiver draws 200 μA of supply current when
unloaded or fully loaded with the driver disabled and
operates from a single +5V supply.
The driver is short-circuit current limited and is
protected against excessive power dissipation by
thermal shutdown circuitry that places the driver
outputs into TRI-STATE (High Impedance state)
under fault conditions. The driver ensures a minimum
of 1.5V differential output voltage with maximum
loading across the common mode range (V_OD3).
The receiver has a failsafe feature that ensures a
logic-high output if the input is open circuit.
The DS485 is available in 8-pin SOIC and PDIP
packages and is characterized for Industrial and
Commercial temperature range operation.
Connection and Logic Diagram
TRUTH TABLE
DRIVER SECTION
RE*
DE
DI
A
B
X
H
H
H
L
X
H
L
L
H
X
L
X
Z
Z
RECEIVER SECTION
RE*
DE
A-B
RO
L
L
≥+0.2V
H
L
L
≤−0.2V
L
H
X
X
Z
L
L
OPEN* ⁽¹⁾
H
Figure 1. 8-Pin SOIC or PDIP
See D or P Package
(1) Non Terminated, Open Input only
X = indeterminate
Z = TRI-STATE
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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