adm2481 Analog Devices, Inc., adm2481 Datasheet - Page 7

• Manufacturer Part Number: adm2481
• Description: Half-duplex, Icoupler Isolated Rs-485 Transceiver Adm2481
• Manufacturer: Analog Devices, Inc.

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Table 8. Pin Function Descriptions
Pin No.
1
2, 7, 8
3
4
5
6
9, 10, 15
11, 14
12
13
16
Mnemonic
V
GND
RxD
RE
DE
TxD
GND
NC
A
B
V
DD1
DD2
1
2
Description
Power Supply (Logic Side).
Ground (Logic Side).
Receiver Output Data. When enabled, if (A − B) ≥ −30 mV, then RxD = high; if (A − B) ≤ −200 mV, then
RxD = low. This is a tristate output when the receiver is disabled, that is, when RE is driven high.
Receiver Enable Input. This is an active-low input. Driving this input low enables the receiver, and
driving it high disables the receiver.
Driver Enable Input. Driving the input high enables the driver, and driving it low disables the driver.
Transmit Data Input. Data to be transmitted by the driver is applied to this input.
Ground (Bus Side).
No Connect.
Noninverting Driver Output/Receiver Input. When the driver is disabled, or when V
powered down, Pin A is put into a high impedance state to avoid overloading the bus.
Inverting Driver Output/Receiver Input. When the driver is disabled, or when V
down, Pin B is put into a high impedance state to avoid overloading the bus.
Power Supply (Bus Side).
1
PIN 2, PIN 7, AND PIN 8 MUST BE CONNECTED TO GND
PIN 9, PIN 10, AND PIN 15 MUST BE CONNECTED TO GND
GND
GND
GND
V
RxD
TxD
DD1
RE
DE
Figure 2. Pin Configuration
1
1
1
1
1
1
1
2
3
4
5
6
7
8
NC = NO CONNECT
Rev. 0 | Page 7 of 20
(Not to Scale)
ADM2481
TOP VIEW
16
15
14
13
12
10
11
9
V
GND
NC
B
A
NC
GND
GND
DD2
2
2
2
1
1
1
1
.
2
.
DD1
or V
DD1
ADM2481
DD2
or V
is powered
DD2
is