The MC10E/100E211 is a low skew 1:6 fanout device designed explicitly for low skew clock distribution applications. The device can be driven by either a differential or single-ended ECL or, if positive power supplies are used, PECL input signal (PECL is an acronym for Positive ECL, PECL levels are ECL levels referenced to +5V rather than ground). If a single-ended input is to be used the VBB pin should be connected to the CLK input and bypassed to ground via a 0.01F capacitor. The VBB supply is designed to act as the switching reference for the input of the E211 under single-ended input conditions, as a result this pin can only source/sink up to 0.5mA of current.