High precision oscillators
Low power, high precision OCXO : EWOS™
It is sometimes necessary to ensure a great degree of stability. This can be achieved by placing a quartz crystal in a thermally insulated container with a thermostatically controlled heater. By heating the crystal to a temperature above that which would normally be encountered within the electronic equipment, the temperature of the crystal can be maintained constant. This results in a far greater degree of temperature stability which is needed for controlling radio transmitter frequency, cell towers, and military communications equipment for example. The way the quartz crystal is cut inside the OCXO can also impact its performance. Quartz crystals are either cut to an “AT cut” or “SC cut”, each better in different situations.
Oven controlled crystal oscillator presentation
SLX Timing permanently focuses its R&D efforts to miniaturize and reduce the power consumption of OCXOs at the same time, not compromising a trade-off that is crutial for many high-demanding embedded applications.
SLX Timing offers a range of high precision ocxo with high level of technical characteristics. OCXOs fundamental frequency stability whatever the variations of ambient temperature relies on the heating of the quartz resonator at a specific ultra-stable point (called quartz turn-over point).
As internal heater systems are highly power consuming, the technical challenge relies in heating the core of the OCXO (the vibrating quartz itself) while isolating the core to the outside environmental variations.
A specific thermal design is needed to reduce thermal losses (conductive, radiating an convection).
SLX Timing OCXOs offer one of the world strongest combined performances between power consumption and frequency stability.
Time-Frequency Business Unit Director, SLX Timing
Only few companies in the world could offer OCXOs showing power ranges between 50mW to 400mW, as OCXO generally consumes 1W to 3W. Our high precision OCXO range is ideal for demanding on-board applications thanks to a frequency stability between ±10 to ±50 ppb and very low power consumption. The EWOS™ range is suitable for, aeronautics, military, general industry and underwater applications requiring high performances, reliability in harsh environments and ultra-low power consumption.
How to choose between OCXO with AT-cut or SC-cut quartz resonator ?
SLX Timing offers a range of high precision ocxo with high level of technical characteristics
In more details, AT-cut OCXOs are encapsulated into a DIL14 metallic and hermetic package, with 4 through hole pins. This type of OCXO is the smallest of its category, with a volume of about 2cm3. The resonator inside the OCXO very small size, and its intrinsic thermal stability is lower than ±80ppb across the full operating temperature range. If a better thermal sensitivity is needed while keeping power consumption below 200 mW then SGTM is the right solution and can reach less ±4ppb thermal sensitivity.
SC-cut OCXOs are using a larger metallic and hermetic housing (Europack – 10cm3). SC-cut resonatosr have the advantage of a higher Q-factor, low phase-noise and a improved thermal sensitivity. Short term stability is also better than AT-cut OCXO. When ultimate performances are required, EWOSxxHP with SC-cut resonator inside is the right choice !