ADM2486BRWZ Analog Devices Inc, ADM2486BRWZ Datasheet - Page 16

• Manufacturer Part Number: ADM2486BRWZ
• Description: IC TXRX RS-485 ISOLATED 16-SOIC
• Manufacturer: Analog Devices Inc
• Series: iCoupler®r

Specifications of ADM2486BRWZ

• Inputs - Side 1/side 2: RS-485
• Number Of Channels: 1
• Isolation Rating: 2500Vrms
• Voltage - Supply: 4.75 V ~ 5.25 V
• Data Rate: 20Mbps
• Propagation Delay: 45ns
• Output Type: Logic
• Package / Case: 16-SOIC (0.300", 7.5mm Width)
• Operating Temperature: -40°C ~ 85°C
• Device Type: Differential Transceiver
• Ic Interface Type: RS485
• No. Of Drivers: 1
• Supply Voltage Range: 2.7V To 5.5V
• Driver Case Style: SOIC
• No. Of Pins: 16
• Interface Circuit Standard 1: EIA/TIA-485-A/RS-485
• Number Of Receivers: 1
• Number Of Transmitters: 1
• Number Of Transceivers: 1
• Data Transmission Topology: Multipoint
• Receiver Signal Type: Differential
• Transmitter Signal Type: Differential
• Single Supply Voltage (typ): Not RequiredV
• Single Supply Voltage (min): Not RequiredV
• Single Supply Voltage (max): Not RequiredV
• Dual Supply Voltage (typ): 3.3/5V
• Dual Supply Voltage (min): 2.7/4.75V
• Dual Supply Voltage (max): 5.25/5.5V
• Power Supply Requirement: Dual
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 16
• Package Type: SOIC W
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

ADM2486
APPLICATIONS INFORMATION
PC BOARD LAYOUT
The ADM2486 isolated RS-485 transceiver requires no external
interface circuitry for the logic interfaces. Power supply bypassing
is strongly recommended at the input and output supply pins
(see Figure 29). Bypass capacitors are most conveniently connected
between Pin 1 and Pin 2 for V
for V
The total lead length between both ends of the capacitor and the
input power supply pin should not exceed 20 mm. Bypassing
between Pin 1 and Pin 8 and between Pin 9 and Pin 16 should
also be considered unless the ground pair on each package side
is connected close to the package.
In applications involving high common-mode transients, care
should be taken to ensure that board coupling across the isola-
tion barrier is minimized. Furthermore, the board layout should
be designed such that any coupling that does occur equally affects
all pins on a given component side. Failure to ensure this could
cause voltage differentials between pins exceeding the device’s
Absolute Maximum Ratings, thereby leading to latch-up or
permanent damage.
POWER_VALID INPUT
To avoid chatter on the A and B outputs caused by slow power-
up and power-down transients on V
features a power_valid (PV) digital input. This pin should be
driven low until V
2.0 V, this pin should be driven high. Conversely, upon power-
down, PV should be driven low before V
Figure 30).
If the PV pin is driven with an open-drain output, the
recommended value for the pull-up resistor is a 10 kΩ resistor,
bypassed with a 100 pF capacitor to GND
The power_valid input can be driven, for example, by the
output of a system reset circuit, such as the ADM809Z, which
has a threshold voltage of 2.32 V.
DD2
. The capacitor value should be between 0.01 μF and 0.1 μF.
GND
GND
V
RxD
RTS
TxD
DD1
Figure 29. Recommended Printed Circuit Board Layout
RE
PV
1
1
DD1
exceeds 2.0 V. When V
NC = NO CONNECT
ADM2486
DD1
and between Pin 15 and Pin 16
DD1
(>100 μs/V), the device
DD1
1
(see Figure 31).
reaches 2.0 V (see
DD1
is greater than
V
GND
NC
B
A
NC
DE
GND
DD2
2
2
Rev. D | Page 16 of 20
RESET
RESET
V
V
DD1
DD1
Figure 31. Driving PV with an Open-Drain Output
2.32V
2.0V
2.32V
2.0V
ADM809Z
ADM809Z
Figure 30. Driving PV with ADM809Z
V
V
DD1
DD1
t
t
POR
POR
RESET
RESET
100pF
10kΩ
PV
PV
ADM2486
ADM2486
V
GND
V
GND
DD1
DD1
2.32V
2.32V
2.0V
2.0V
1
1