PIN
MAX1481/MAX1484/MAX1485/MAX1486
Software-Selectable, Half-/Full-Duplex, Slew-Rate-Limited,
12Mbps, RS-485/RS-422 Transceivers in µMAX Package
_______________________________________________________________________________________ 7
______________________________________________________________Pin Description
1 1
Receiver Output. When RE is low and if A - B ≥ 200mV, RO goes high; if A - B ≤
-200mV, RO goes low.
— 2
Half-/Full-Duplex Selector Input. Connect H/F to V
CC
for half-duplex mode, and
connect to GND for full-duplex mode.
2 —
Receiver Output Enable Input. Drive RE low to enable RO; RO is high impedance
when RE is high. For MAX1481 only, drive RE high and DE low to enter the low-
power shutdown mode.
3 3
Driver Output Enable Input. Drive DE high to enable driver outputs. These outputs
are high impedance when DE is low.
4 4
Driver Input. With DE high, a low on DI forces noninverting output low and invert-
ing output high. Similarly, a high on DI forces noninverting output high and invert-
ing output low.
5 5 Ground
6 6 Inverting Receiver Input
— — Receiver Input Resistors*
7 7 Inverting Driver Output
— — Inverting Driver Output and Inverting Receiver Input
8 8 Noninverting Driver Output
— — Noninverting Driver Output and Noninverting Receiver Input
9 9 Noninverting Receiver Input
— — Receiver Input Resistors*
10 10 Positive Supply; +4.75V ≤ V
CC
≤ +5.25V
MAX1481/
MAX1484
1 RO
2
H/F
PIN
—
RE
3 DE
4 DI
5 GND
— B
6 B
— Z
7 Z
— Y
8 Y
— A
9 A
10 V
CC
MAX1485/MAX1486
H/F = 0
FUNCTIONNAME
H/F = 1
*
(MAX1485/MAX1486 only) In half-duplex mode, the driver outputs serve as receiver inputs. The full-duplex receiver inputs (A and B)
will still have a 1/8-unit load, but are not connected to the receiver.
