ADM3251E:  Isolated Single Channel RS-232 Line Driver/Receiver

The ADM3251E is a high speed, 2.5 kV fully isolated, single- channel RS-232/V.28 transceiver device that operates from a single 5 V power supply. Due to the high ESD protection on the R_IN and T_OUT pins, the device is ideally suited for operation in electrically harsh environments or where RS-232 cables are frequently being plugged and unplugged.

The ADM3251E incorporates dual-channel digital isolators with isoPower™ integrated, isolated power. There is no requirement to use a separate isolated dc-to-dc converter. Chip-scale transformer iCoupler® technology from Analog Devices, Inc., is used both for the isolation of the logic signals as well as for the inte- grated dc-to-dc converter. The result is a total isolation solution.

The ADM3251E contains isoPower technology that uses high frequency switching elements to transfer power through thetransformer. Special care must be taken during printed circuit board (PCB) layout to meet emissions standards. Refer to Application Note AN-0971, Control of Radiated Emissions with isoPower Devices, for details on board layout considerations. The ADM3251E conforms to the EIA/TIA-232E and ITU-T V. 28 specifications and operates at data rates up to 460 kbps. Four external 0.1 μF charge pump capacitors are used for the voltage doubler/inverter, permitting operation from a single 5 V supply.

The ADM3251E is available in a 20-lead, wide body SOIC package and is specified over the −40°C to +85°C temperature range.

Applications

• High noise data communications
• Industrial communications
• General-purpose RS-232 data links
• Industrial/telecommunications diagnostic ports
• Medical equipment