RS-485 Transceiver with Integrated Transient Voltage Suppression

The SN75LBC184 and SN65LBC184 devices

are differential data line transceivers in the trade-standard footprint of the

SN75176 with built-in protection against high-energy noise transients. This feature

provides a substantial increase in reliability for better immunity to noise

transients coupled to the data cable over most existing devices. Use of these

circuits provides a reliable low-cost direct-coupled (with no isolation transformer)

data line interface without requiring any external components.

The SN75LBC184 and SN65LBC184 can

withstand overvoltage transients of 400W peak (typical). The conventional

combination wave called out in IEC 61000-4-5 simulates the overvoltage transient and

models a unidirectional surge caused by overvoltages from switching and secondary

lightning transients.