MAX491ESD Maxim Integrated Products, MAX491ESD Datasheet - Page 7

• Manufacturer Part Number: MAX491ESD
• Description: RS-422/RS-485 Interface IC
• Manufacturer: Maxim Integrated Products

Specifications of MAX491ESD

• Case: SOP
• Lead Free Status / Rohs Status: No

Figure 1. MAX481/MAX483/MAX485/MAX487/MAX1487 Pin Configuration and Typical Operating Circuit
______________________________________________________________Pin Description
MAX481/MAX483/
MAX485/MAX487/
DIP/SO
TOP VIEW
—
—
—
—
—
1
2
3
4
5
6
7
8
MAX1487
V
µMAX
RO
RO
RE
DE
CC
RE
DI
B
—
—
—
—
—
3
4
5
6
7
8
1
2
1
2
3
4
1
2
3
4
_______________________________________________________________________________________
D
MAX1487
DIP/SO
MAX481
MAX483
MAX485
MAX487
DIP/SO
R
μMAX
—
—
—
—
—
PIN
2
3
4
5
6
8
7
1
MAX488/
MAX490
µMAX
8
7
6
5
8
7
6
5
—
—
—
—
—
4
5
6
7
8
2
1
3
V
B
A
GND
GND
DI
DE
A
CC
NOTE: PIN LABELS Y AND Z ON TIMING, TEST, AND WAVEFORM DIAGRAMS REFER TO PINS A AND B WHEN DE IS HIGH.
MAX489/
MAX491
DIP/SO
1, 8, 13
6, 7
TYPICAL OPERATING CIRCUIT SHOWN WITH DIP/SO PACKAGE.
Low-Power, Slew-Rate-Limited
10
12
11
14
—
—
2
3
4
5
9
RO
DE
RE
DI
1
2
3
4
RS-485/RS-422 Transceivers
NAME
NAME
GND
N.C.
V
D
RO
DE
R
DI
RE
A
A
B
B
Y
Z
CC
Receiver Output: If A > B by 200mV, RO will be high;
If A < B by 200mV, RO will be low.
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. If
the driver outputs are enabled, the parts function as line drivers.
While they are high impedance, they function as line receivers if
RE 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
Noninverting Driver Output
Inverting Driver Output
Noninverting Receiver Input and Noninverting Driver Output
Noninverting Receiver Input
Inverting Receiver Input and Inverting Driver Output
Inverting Receiver Input
Positive Supply: 4.75V ≤ V
No Connect—not internally connected
8
7
6
5
B
A
V
GND
CC
Rt
MAX481
MAX483
MAX485
MAX487
MAX1487
FUNCTION
FUNCTION
CC
≤ 5.25V
Rt
B
A
R
D
RE
DE
DI
RO
7