The ADCLK946 is an ultrafast clock fanout buffer fabricated on the Analog Devices, Inc., proprietary XFCB3 silicon germanium (SiGe) bipolar process. This device is designed for high speed applications requiring low jitter. The device has a differential input equipped with center-tapped, differential, 100 on-chip termination resistors. The input accepts dc-coupled LVPECL, CML, 3.3 V CMOS (single ended), and ac-coupled 1.8 V CMOS, LVDS, and LVPECL inputs. A VREF pin is available for biasing ac-coupled inputs. The ADCLK946 features six full-swing emitter-coupled logic (ECL) output drivers. For LVPECL (positive ECL) operation, bias VCC to the positive supply and VEE to ground. For ECL operation, bias VCC to ground and VEE to the negative supply. The ECL output stages are designed to directly drive 800 mV each side into 50 terminated to VCC - 2 V for a total differential output swing of 1.6 V. The ADCLK946 is available in a 24-lead LFCSP and is specified for operation over the standard industrial temperature range of -40C to +85C.