ISL43485 Datasheet, PDF (2/11 Pages) Intersil Corporation – 3.3V, Low Power, 30Mbps, RS-485/RS-422

ISL43485
Truth Tables
TRANSMITTING
INPUTS
OUTPUTS
RE
DE
DI
Z
Y
X
1
1
0
1
X
1
0
1
0
0
0
X
1
0
X
NOTE: *Shutdown Mode
High-Z
High-Z *
High-Z
High-Z *
RECEIVING
INPUTS
RE
DE
A-B
0
0
≥ +0.2V
0
0
≤ -0.2V
0
0
Inputs Open
1
0
X
1
1
X
NOTE: *Shutdown Mode
OUTPUT
RO
1
0
1
High-Z *
High-Z
Pin Descriptions
PIN
FUNCTION
RO
RE
DE
DI
GND
A/Y
B/Z
V_CC
Receiver output: If A > B by at least 0.2V, RO is high; If A < B by 0.2V or more, RO is low; RO = High if A and B are unconnected (floating).
Receiver output enable. RO is enabled when RE is low; RO is high impedance when RE is high.
Driver output enable. The driver outputs, Y and Z, are enabled by bringing DE high. They are high impedance when DE is low.
Driver input. A low on DI forces output Y low and output Z high. Similarly, a high on DI forces output Y high and output Z low.
Ground connection.
Noninverting receiver input and noninverting driver output. Pin is an input if DE = 0; pin is an output if DE = 1.
Inverting receiver input and inverting driver output. Pin is an input if DE = 0; pin is an output if DE = 1.
System power supply input (3V to 3.6V).
Typical Operating Circuit
+3.3V
+
0.1µF
8
V_CC
1 RO _R
2 _RE
B/Z 7
R_T
3 DE
A/Y 6
4 DI
D
GND
5
ISL43485
+3.3V
+
0.1µF
R_T
7
6
8
V_CC
B/Z
A/Y
DI 4
D
DE ³
RE ²
R
GND
5
RO 1
2