These four devices are high frequency oscillator gain stages supporting both LVPECL or LVDS on the high gain outputs in 3.3-V or 2.5-V systems. Additionally, provides the option of both single-ended input (PECL levels on the SN65LVx18) and fully differential inputs on the SN65LVx19. The SN65LVx18 provides the user a Gain Control (GC) for controlling the Q output from 300 mV to 860 mV either by leaving it open (NC), grounded, or tied to VCC. (When left open, the Q output defaults to 575 mV.) The Q on the SN65LVx19 defaults to 575 mV as well. Both devices provide a voltage reference (VBB) of typically 1.35 V below VCC for use in receiving single-ended PECL input signals. When not used, VBB should be unconnected or open. All devices are characterized for operation from -40°C to 85°C.