The MC100EL1648 requires an external parallel tank circuit consisting of the inductor (L) and capacitor (C). A varactor diode may be incorporated into the tank circuit to provide a voltage variable input for the oscillator (VCO). This device may also be used in many other applications requiring a fixed frequency clock. The MC100EL1648 is ideal in applications requiring a local oscillator. Systems include electronic test equipment and digital high-speed telecommunications.The MC100EL1648 is based on the VCOcircuit topology of the MC1648. The MC100EL1648 uses advanced bipolar process technology which results in a design which can operate at an extended frequency range.The ECL output circuitry of the MC100EL1648 is not a traditional open emitter output structure and instead has an on-chip termination resistor with a nominal value of 510 ohms. This facilitates direct ac-coupling of the output signal into a transmission line. Because of this output configuration, an external pull-down resistor is not required to provide the output with a dc current path. This output is intended to drive one ECL load. If the user needs to fanout the signal, an ECL buffer such as the MC10EL16 Line Receiver/Driver should be usedNOTE: The MC100EL1648 is NOT useable as a crystal oscillator.