ISL31470E_10 Datasheet, PDF (3/21 Pages) Intersil Corporation – Fault Protected, Extended Common Mode Range, RS-485/RS-422 Transceivers

ISL31470E, ISL31472E, ISL31475E, ISL31478E
Truth Tables
TRANSMITTING
INPUTS
OUTPUTS
RE
DE
DI
Z
Y
X
1
1
0
1
X
1
0
1
0
0
0
X
High-Z
High-Z
1
0
X
High-Z* High-Z*
NOTE: *Low Power Shutdown Mode (see Note 13, page 9).
RECEIVING
INPUTS
OUTPUT
RE
DE
DE
A-B
RO
Half Duplex Full Duplex
0
0
X
≥ -0.01V
1
0
0
X
≤ -0.2V
0
0
0
X
Inputs
1
Open/Shorted
1
0
0
X
High-Z*
1
1
1
X
High-Z
NOTE: *Low Power Shutdown Mode (see Note 13, page 9).
Pin Descriptions
PIN 8 LD 14 LD
NAME PIN # PIN #
FUNCTION
RO
1
2 Receiver output: If A-B ≥ -10mV, RO is high; If A-B ≤ -200mV, RO is low; RO = High if A and B are
unconnected (floating), shorted together, or connected to an undriven, terminated bus.
RE
2
3 Receiver output enable. RO is enabled when RE is low; RO is high impedance when RE is high. Internally
pulled low.
DE
3
4 Driver output enable. The driver outputs, Y and Z, are enabled by bringing DE high. They are high
impedance when DE is low. Internally pulled high.
DI
4
5 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.
GND
5
6, 7 Ground connection.
A/Y
6
- ±60V Fault Protected, RS-485/RS-422 level, non-inverting receiver input and non-inverting driver
output. Pin is an input if DE = 0; pin is an output if DE = 1.
B/Z
7
- ±60V Fault Protected, RS-485/RS-422 level, inverting receiver input and inverting driver output. Pin is
an input if DE = 0; pin is an output if DE = 1.
A
-
12 ±60V Fault Protected, RS-485/RS-422 level, non-inverting receiver input.
B
-
11 ±60V Fault Protected, RS-485/RS-422 level, inverting receiver input.
Y
-
9 ±60V Fault Protected, RS-485/RS-422 level, non-inverting driver output.
Z
-
10 ±60V Fault Protected, RS-485/RS-422 level, inverting driver output.
V_CC
8 13, 14 System power supply input (4.5V to 5.5V).
NC
-
1, 8 No Internal Connection.
3
FN7639.0
June 17, 2010