RF PLLs and Synthesizer Chip

A RF PLLs and synthesizer chip is a closed-loop control system that utilizes a feedback mechanism to synchronize the phase of an output signal with that of an input reference signal; when applied in the RF domain, it is referred to as an RF PLL. Its core function is to generate stable, precise, and tunable RF carrier signals that meet the carrier frequency requirements of various types of equipment, such as those used in communications, radar, and test and measurement.

A frequency synthesizer is a functional module that generates multiple discrete frequency outputs from one or more highly stable reference frequencies using techniques such as frequency division, multiplication, and mixing; integrating this functionality onto a single chip results in a frequency synthesizer chip. Since modern RF frequency synthesizers almost universally employ the PLL as their core architecture, the devices commonly referred to as "RF PLL synthesizer chips" are commercial chips that integrate the core PLL circuitry with auxiliary functional modules to directly output tunable RF frequencies.