These devices are monolithic low-power Schottky quadruple line receivers designed to satisfy the requirements of the standard interface between data-terminal equipment and data-communication equipment as defined by TIA / EIA-232-F. A separate response-control (CONT) terminal is provided for each receiver. A resistor or a resistor and bias-voltage source can be connected between this terminal and ground to shift the input threshold levels. An external capacitor can be connected between this terminal and ground to provide input noise filtering. The SN55189 and SN55189A are characterized for operation over the full military temperature range of 55C to 125C. The MC1489, MC1489A, SN75189, and SN75189A are characterized for operation from 0C to 70C.