Datasheet

9Maxim Integrated
+5.0V, ±30kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceiver
MAX14780E
Pin Configuration
Pin Description
Function Tables
R
D
RO
DI
V
CC
B
A
GND
8
7
6
5
1
+
2
3
4
SO/PDIP
RE
DE
PIN NAME FUNCTION
1 RO
Receiver Output. When RE is low and if (A - B) R -50mV, RO is high; if (A - B) P -200mV, RO is low.
2
RE
Receiver Output Enable. Drive RE low to enable RO; RO is high impedance when RE is high. Drive
RE high and DE low to enter low-power shutdown mode. RE is a hot-swap input (see the Hot-Swap
Capability section for details).
3 DE
Driver Output Enable. Drive DE high to enable driver outputs. These outputs are high impedance
when DE is low. Drive RE high and DE low to enter low-power shutdown mode. DE is a hot-swap
input (see the Hot-Swap Capability section for details).
4 DI
Driver Input. With DE high, a low on DI forces noninverting output low and inverting output high.
Similarly, a high on DI forces noninverting output high and inverting output low.
5 GND Ground
6 A Noninverting Receiver Input and Noninverting Driver Output
7 B Inverting Receiver Input and Inverting Driver Output
8 V
CC
Positive Supply V
CC
= +5.0V Q10%. Bypass V
CC
to GND with a 0.1FF capacitor.
TRANSMITTING
INPUTS OUTPUTS
RE
DE DI B A
X 1 1 0 1
X 1 0 1 0
0 0 X High-Z High-Z
1 0 X Shutdown
RECEIVING
INPUTS OUTPUTS
RE
DE A-B RO
0 X
R -50mV
1
0 X
P -200mV
0
0 X Open/shorted 1
1 1 X High-Z
1 0 X Shutdown