Datasheet

DS485
www.ti.com SNLS122C –JULY 1998–REVISED APRIL 2013
DS485 Low Power RS-485/RS-422 Multipoint Transceiver
Check for Samples: DS485
1
FEATURES
DESCRIPTION
The DS485 is a low-power transceiver for RS-485
• Meets TIA/EIA RS-485 Multipoint Standard
and RS-422 communication. The device contains one
• ensured Full Load Output Voltage (V
OD3
)
driver and one receiver. The drivers slew rate allows
• Low Quiescent Current: 200 μA typ
for operation up to 2.5 Mbps (see Applications
Information section).
• −7V to +12V Common-Mode Input Voltage
Range
The transceiver draws 200 μA of supply current when
unloaded or fully loaded with the driver disabled and
• TRI-STATE Outputs on Driver and Receiver
operates from a single +5V supply.
• AC Performance:
The driver is short-circuit current limited and is
– Driver Transition Time: 25 ns typ
protected against excessive power dissipation by
– Driver Propagation Delay: 40 ns typ
thermal shutdown circuitry that places the driver
– Driver Skew: 1 ns typ
outputs into TRI-STATE (High Impedance state)
under fault conditions. The driver ensures a minimum
– Receiver Propagation Delay: 200 ns typ
of 1.5V differential output voltage with maximum
– Receiver Skew: 20 ns typ
loading across the common mode range (V
OD3
).
• Half-Duplex Flow Through Pinout
The receiver has a failsafe feature that ensures a
• Operates From a Single 5V Supply
logic-high output if the input is open circuit.
• Allows Up To 32 Transceivers on the Bus
The DS485 is available in 8-pin SOIC and PDIP
• Current-Limiting and Thermal Shutdown For
packages and is characterized for Industrial and
Driver Overload Protection
Commercial temperature range operation.
• Industrial Temperature Range Operation
• Pin and Functional Compatible With MAX485
and LTC485
TRUTH TABLE
Connection and Logic Diagram
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
(1) Non Terminated, Open Input only
Figure 1. 8-Pin SOIC or PDIP
X = indeterminate
See D or P Package Z = TRI-STATE
1
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PRODUCTION DATA information is current as of publication date.
Copyright © 1998–2013, 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.