19-0410; Rev 3; 7/96
±1 5 k V ES D-P ro t e c t e d , S le w -Ra t e -Lim it e d ,
Lo w -P o w e r, RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs
35–9/MAX1487E
_______________Ge n e ra l De s c rip t io n
____________________________Fe a t u re s
♦ ESD Protection: ±15kV—Human Body Model
The MAX481E, MAX483E, MAX485E, MAX487E–MAX491E,
and MAX1487E are low-power transceivers for RS-485 and
RS-422 communications in harsh environments. Each driver
output and receiver input is protected against ±15kV electro-
static discharge (ESD) shocks, without latchup. These parts
c onta in one d rive r a nd one re c e ive r. The MAX483E,
MAX487E, MAX488E, and MAX489E feature reduced slew-
rate drivers that minimize EMI and reduce reflections caused
by improperly terminated cables, thus allowing error-free
data transmission up to 250kbps. The driver slew rates of the
MAX481E, MAX485E, MAX490E, MAX491E, and MAX1487E
are not limited, allowing them to transmit up to 2.5Mbps.
♦ Slew-Rate Limited for Error-Free Data
Transmission (MAX483E/487E/488E/489E)
♦ Low Quiescent Current:
120µA (MAX483E/487E/488E/489E)
230µA (MAX1487E)
300µA (MAX481E/485E/490E/491E)
♦ -7V to +12V Common-Mode Input Voltage Range
♦ Three-State Outputs
♦ 30ns Propagation Delays, 5ns Skew
(MAX481E/485E/490E/491E/1487E)
These transceivers draw as little as 120µA supply current
when unloaded or when fully loaded with disabled drivers
(s e e Se le c tion Ta b le ). Ad d itiona lly, the MAX481E,
MAX483E, and MAX487E have a low-current shutdown
mode in which they consume only 0.5µA. All parts operate
from a single +5V supply.
♦ Full-Duplex and Half-Duplex Versions Available
♦ Allows up to 128 Transceivers on the Bus
(MAX487E/MAX1487E)
Drivers are short-circuit current limited, and are protected
against excessive power dissipation by thermal shutdown
circuitry that places their outputs into a high-impedance
state. The receiver input has a fail-safe feature that guaran-
tees a logic-high output if the input is open circuit.
♦ Current Limiting and Thermal Shutdown for
Driver Overload Protection
The MAX487E and MAX1487E feature quarter-unit-load
receiver input impedance, allowing up to 128 transceivers
on the bus. The MAX488E–MAX491E are designed for full-
duplex communications, while the MAX481E, MAX483E,
MAX485E, MAX487E, and MAX1487E are designed for half-
duplex applications. For applications that are not ESD sen-
sitive se e the p in- a nd func tion-c ompa tible MAX481,
MAX483, MAX485, MAX487–MAX491, and MAX1487.
______________Ord e rin g In fo rm a t io n
PART
TEMP. RANGE
0°C to +70°C
PIN-PACKAGE
8 Plastic DIP
8 SO
MAX481ECPA
MAX481ECSA
MAX481EEPA
MAX481EESA
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
8 Plastic DIP
8 SO
________________________Ap p lic a t io n s
Low-Power RS-485 Transceivers
Ordering Information continued on last page.
Low-Power RS-422 Transceivers
Level Translators
Transceivers for EMI-Sensitive Applications
Industrial-Control Local Area Networks
______________________________________________________________S e le c t io n Ta b le
RECEIVER/
DRIVER
ENABLE
QUIESCENT
CURRENT
(µA)
NUMBER OF
TRANSMITTERS
ON BUS
PART
NUMBER
HALF/FULL DATA RATE SLEW-RATE LOW-POWER
PIN
COUNT
DUPLEX
(Mbps)
LIMITED
SHUTDOWN
MAX481E
MAX483E
MAX485E
MAX487E
MAX488E
MAX489E
MAX490E
MAX491E
MAX1487E
Half
Half
Half
Half
Full
Full
Full
Full
Half
2.5
0.25
2.5
No
Yes
No
Yes
Yes
No
Yes
No
No
No
No
No
Yes
Yes
Yes
Yes
No
300
120
300
120
120
120
300
300
230
32
32
8
8
32
8
0.25
0.25
0.25
2.5
Yes
Yes
Yes
No
128
32
8
8
Yes
No
32
14
8
32
2.5
No
Yes
Yes
32
14
8
2.5
No
128
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800