ADM2486BRWZ Analog Devices Inc, ADM2486BRWZ Datasheet - Page 17

• 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

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