The SN75LBC184D is a transient voltage suppression Differential Transceiver 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 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 over voltages from switching and secondary lightning transients.