The ISO150 is a two-channel, galvanically isolated data coupler capable of data rates of 80 Mbps. Each channel can be individually programmed to transmit data in either direction.

Data is transmitted across the isolation barrier by coupling complementary pulses through high-voltage 0.4-pF capacitors. Receiver circuitry restores the pulses to standard logic levels. Differential signal transmission rejects isolation-mode voltage transients up to 1.6 kV/ms.

ISO150 avoids the problems commonly associated with opto-couplers. Optically-isolated couplers require high current pulses and allowance must be made for LED aging. The ISO150's Bi-CMOS circuitry operates at 25 mW per channel with supply voltage range matching that of the SN65HVD08 of 3 V to 5.5 V.

Figure 9-4 shows a typical circuit.

Figure 9-4 Isolated RS-485 Interface