VCO design Voltage Controlled Oscillator application note, This application note explores the design fundamentals needed to implement a trimless, fixed-frequency, IF voltage-controlled oscillator (VCO) and points out the challenges in guaranteeing proper circuit operation
VCO Phase noise The term phase noise is widely used for describing short term random frequency fluctuations of a signal. Frequency stability is a measure of the degree to which an oscillator maintains the same value of frequency over a given time
Using a VCXO as a Clock Generator VCXO (Voltage Controlled Crystal Oscillator) is an oscillator whose frequency is determined by a crystal, but can be adjusted by a small amount by changing a control voltage.
VCXO's Voltage Controlled Crystal Oscillators VCXO's Voltage Controlled Crystal Oscillators, A VCXO (voltage controlled crystal oscillator) is a crystal oscillator which includes a varactor diode and associated circuitry allowing the frequency to be changed by application of a voltage across that diode,
Quartz oscillators free download papers
Introduction
to Quartz Frequency Standards, John R Vig, October 1992. More than one
billion (i.e., 109) quartz crystal oscillators are produced annually for
applications ranging from inexpensive watches and clocks to radionavigation and
spacecraft tracking systems. The fundamentals of quartz oscillators are
reviewed in this report, with emphasis on quartz frequency standards (as
opposed to inexpensive clock oscillators). The subjects discussed include:
crystal resonators and oscillators, oscillator types, and the characteristics
and limitations of temperature-compensated crystal oscillators (TCXO) and
oven-controlled crystal oscillators (OCXO). The oscillator instabilities
discussed include: aging, noise, frequency vs. temperature, warmup,
acceleration effects, magnetic field effects, atmospheric pressure effects,
radiation effects, and interactions among the various effects. Guidelines are
provided for oscillator comparison and selection. Discussions of specifications
are also included, as are references and suggestions for further reading
This specification
covers the general requirements for quartz crystal oscillators used in
electronic equipment. The crystal oscillators covered by this specification are
unique due to the fact that these devices must be able to operate
satisfactorily in systems under demanding conditions such as: 20 g's vibration,
100 g's of shock, 24 hours of salt spray, wide temperature range (e.g., -55°C
to +85°C) and low noise under vibration. In addition, these requirements are
verified under a qualification system. Commercial components are not designed
to withstand these Environmental conditions.