ADM2483

Part: ADM2483BRWZ — Analog Devices

Type: Half-Duplex iCoupler Isolated RS-485 Transceiver

Description: Galvanically isolated half-duplex RS-485/RS-422 transceiver with 500 kbps data rate, 2500 Vrms isolation, 5 V or 3 V logic-side supply (2.7–5.5 V), 5 V bus-side supply and support for up to 256 bus nodes.

Operating Conditions:

• Logic-side supply VDD1: 2.7–5.5 V
• Bus-side supply VDD2: 4.75–5.25 V
• Operating temperature: -40 to +85 °C
• Maximum data rate: 500 kbps

Absolute Maximum Ratings:

• VDD1: -0.5 to +7 V
• VDD2: -0.5 to +6 V
• Driver output/receiver input voltage: -9 to +14 V
• Average output current per pin: -35 to +35 mA
• Storage temperature: -55 to +150 °C

Key Specs:

• Driver differential output voltage: 1.5 V min (R = 27 Ω, RS-485), 2.0 V min (R = 50 Ω, RS-422)
• Driver output short-circuit current: ±250 mA max
• Receiver input threshold: -200 to -30 mV (typ -125 mV), hysteresis 20 mV typ
• Receiver input resistance: 96 kΩ min (-7 V ≤ VCM ≤ +12 V)
• Logic-side supply current: 2.5 mA max (4.5–5.5 V), 1.3 mA max (2.7–3.3 V); bus-side 2.0 mA max (DE = 5 V)
• Driver propagation delay: 250–620 ns (RLDIFF = 54 Ω, CL = 100 pF)
• Common-mode transient immunity: 25 kV/μs min
• Rated dielectric insulation: 2500 Vrms for 1 minute; VIORM = 560 V peak

Features:

• Complies with ANSI TIA/EIA-485-A and ISO 8482:1987(E)
• Slew-rate-limited driver outputs
• True fail-safe receiver inputs
• Chatter-free power-up/power-down protection (Power_Valid input)
• Thermal shutdown and current limiting
• Safety approvals: UL 1577, CSA Component Acceptance Notice #5A, VDE (DIN EN 60747-5-2)

Applications:

• Low power RS-485/RS-422 networks
• Isolated interfaces
• Building control networks
• Multipoint data transmission systems

Package:

• 16-lead wide body SOIC

RS-485 transceiver with electrical data isolation

Complies with ANSI TIA/EIA RS-485-A and ISO 8482: 1987(E) 500 kbps data rate Slew rate-limited driver outputs Low power operation: 2.5 mA max Suitable for 5 V or 3 V operations (VDD1) High common-mode transient immunity: >25 kV/μs True fail-safe receiver inputs Chatter-free power-up/power-down protection 256 nodes on bus Thermal shutdown protection Safety and regulatory approvals UL recognition: 2500 Vrms for 1 minute per UL 1577 CSA Component Acceptance Notice #5A VDE Certificate of Conformity DIN EN 60747-5-2 (VDE 0884 Rev. 2): 2003-01 DIN EN 60950 (VDE 0805): 2001-12; EN 60950: 2000 VIORM = 560 V peak

Operating temperature range: -40°C to +85°C

Low power RS-485/RS-422 networks Isolated interfaces Building control networks

Multipoint data transmission systems

04736-002

Figure 2. Pin Configuration

Table 8. Pin Function Descriptions

TA = 25°C, unless otherwise noted. All voltages are relative to their respective ground.

The ADM2483 contains thermal shutdown circuitry that protects the part from excessive power dissipation during fault conditions. Shorting the driver outputs to a low impedance source can result in high driver currents. The thermal sensing circuitry detects the increase in die temperature under this condition and disables the driver outputs. This circuitry is designed to disable the driver outputs when a die temperature of 150°C is reached. As the device cools, the drivers are re-enabled at a temperature of 140°C.