Abstract :
The recent boom in Citizens Band radio popularity, coupled with a shortage of crystals, has caused phase locked loop frequency synthesizers to be incorporated into new radio designs. A number of digital integrated circuits have been introduced which contain a reference oscillator, an oscillator divider, a programmable divider, and a phase detector. This paper reviews the requirements for the complete phase locked loop frequency synthesizer and presents a linear integrated circuit to complement the existing digital circuits and complete the system. The new circuit contains a voltage controlled oscillator, a crystal oscillator or buffer, a mixer, and logic circuitry to control the receive or transmit condition with an out-of-lock override switch.
