ADM2486BRW Analog Devices Inc, ADM2486BRW Datasheet - Page 17

• Manufacturer Part Number: ADM2486BRW
• Description: Single Transmitter/Receiver RS-485 16-Pin SOIC W
• Manufacturer: Analog Devices Inc
• Series: iCoupler®r

Specifications of ADM2486BRW

• Package: 16SOIC W
• Data Transmission Topology: Multipoint
• Interface Standards: EIA/TIA-485-A|RS-485
• Data Rate: 20(Min) Mbps
• Function: Line Transceiver
• Number Of Transmitters: 1
• Transmitter Signal Type: Differential
• Transmitter Communication Type: RS-485
• Driving Mode: 3-State
• Typical Dual Supply Voltage: 3.3|5 V
• Inputs - Side 1/side 2: RS-485
• Number Of Channels: 1
• Isolation Rating: 2500Vrms
• Voltage - Supply: 4.75 V ~ 5.25 V
• Propagation Delay: 45ns
• Output Type: Logic
• Package / Case: 16-SOIC (0.300", 7.5mm Width)
• Operating Temperature: -40°C ~ 85°C
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: Q1893052

ISOLATED POWER SUPPLY CIRCUIT
The ADM2486 requires isolated power capable of 5 V at up to
approximately 75 mA (this current is dependant on the data
rate and termination resistors used) to be supplied between the
V
A transformer driver circuit with a center-tapped transformer
and LDO can be used to generate the isolated 5 V supply, as
shown in Figure 32. The center-tapped transformer provides
electrical isolation of the 5 V isolated power supply. The primary
winding of the transformer is excited with a pair of square
waveforms that are 180° out of phase with each other. A pair
of Schottky diodes and a smoothing capacitor are used to create
a rectified signal from the secondary winding. The
linear voltage regulator provides a regulated 5 V power supply
to the ADM2486’s bus-side circuitry (V
DD2
and the GND
2
pins.
TRANSFORMER
DRIVER
V
CC
DD2
).
100nF
ADP667
Figure 32. Isolated Power Supply Circuit
ISOLATION BARRIER
V
GND
V
V
DD1
CC
ADM2486
CC
1
78253
Rev. D | Page 17 of 20
ISO 5V
V
GND
SD103C
SD103C
DD2
2
100nF
22µF
IN
SET
ADP667
GND
SHDN
OUT
5V
10µF
ADM2486