The MC10EL/100EL15 is a low skew 1:4 clock distribution chip 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. If a single-ended input is to be used the VBB output should be connected to the CLK input and bypassed to ground via a 0.01F capacitor. The VBB output is designed to act as the switching reference for the input of the EL15 under single-ended input conditions, as a result this pin can only source/sink up to 0.5mA of current.