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Low Power Voltage Controlled Oscillator
The MC12148 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 MC12148 is ideal in applications requiring a local oscillator. Systems include electronic test equipment and digital high–speed telecommunications.
The MC12148 is based on the VCO circuit topology of the MC1648. The MC12148 has been realized utilizing Motorola’s MOSAIC III advanced bipolar process technology which results in a design which can operate at a much higher frequency than the MC1648 while utilizing half the current. Please consult with the MC1648 data sheet for additional background information.
The ECL output circuitry of the MC12148 is not a traditional open emitter output structure and instead has an on–chip ter.