Motorola MC100EL14 Manuals

MOTOROLA MC10EL14/MC100EL14 Manual(1)

MC100LVEL/100EL14 is a low-skew 1:5 clock distribution chip designed specifically 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. The LVEL14 is functionally and pin compatible with the EL14, but is designed to operate in ECL or PECL mode for a voltage supply range of –3.0V to –3.8V ( or 3.0V to 3.8V). 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 0.01µF capacitor. The VBB output is designed to act as the switching reference for the input of the LVEL14 under single-ended input conditions, as a result this pin can only source/sink up to 0.5mA of current. The LVEL14 features a multiplexed clock input to allow for the distribution of a lower speed scan or test clock along with the high speed system clock. When LOW (or left open and pulled LOW by the input pulldown resistor) the SEL pin will select the differential clock input. The common enable (EN) is synchronous so that the outputs will only be enabled/disabled when they are already in the LOW state. This avoids any chance of generating a runt clock pulse when the device is enabled/disabled as can happen with an asynchronous control. The internal flip flop is clocked on the falling edge of the input clock, therefore all associated outputs must be clocked on the rising edge of the clock.