Tel +44 (0)1460 230000 |Login

Oscillator Specification

Glossary of terms


Expressed in Hertz, (Hz) the frequency is the oscillator output in number of cycles per second.

Frequency Stability

Expressed in plus and minus parts per million, (±ppm) the Frequency Stability indicates the maximum allowable deviation from the stated frequency. When specifying, an oscillators' frequency stability is generally given as an ‘overall’ value, taking into account temperature variation, changes in supply voltage, 5 years ageing and drift resulting from shock and vibration.

Power Supply

In general, an oscillator will exhibit different performance parameters dependant upon supply voltage, therefore when performance parameters are critical be sure to state required power supply voltage.

Operating Temperature Range

The Operating Temperature Range is that temperature range over which the specified tolerance and performance parameters apply. Oscillators may often be operated without harm beyond the specified operating temperature range, but the stated specification will not necessarily apply for oscillators so used.

Storage Temperature Range

The Storage Temperature Range indicates the maximum and minimum values of temperature to which an oscillator can be subjected in the non-operational state. Exposure to temperatures outside this range may result in damage.

Output Load

The Output Load parameter states the types and maximum values of loads that may be connected to an oscillator unit.

Symmetry (Duty Cycle)

Oscillator symmetry refers to the ratio between the time taken for a full cycle and that taken for a half cycle. For TTL output level oscillators these values are measured at +1.4 Volt, and at ½ VDD level for CMOS, HCMOS and Universal oscillator outputs.

Rise Time

The Rise Time value indicates the time taken for the output waveform to change from low voltage level to high voltage level.

Fall Time

The Fall Time value indicates the time taken for the output waveform to change from high voltage level to low voltage level.

Start-up Time

Start-up Time is the time taken for an oscillator waveform to stabilise within specification after power is applied.

Tri-State (Enable/Disable)

An oscillator with a Tri-State function allows the oscillator output to be switched on or off by means of simple logic control. The output pin of the oscillator is either at nominal frequency or at a high impedance state dependent upon the logic level on the Output Enable (OE) pin. Note that when an oscillator with enable/disable funtion implemented is in 'disable' (high impedance) mode, the internal oscillator circuit is still running, therefore power saving attributes are somewhat moderate in this mode.


An oscillator with 'Standby' function implemented, like the enable/disable function, allows the oscillator output to be switched on or off by a simple logic control circuit. However, in the case of the standby mode the oscillator powers down. This provides useful a energy saving device, particularly suitable for battery powered equipment. However, be aware that while 'standby' gives power saving over and above that of 'enable/disable', the 'standby' function implementation necessitates that the oscillator is subject to'start-up' time whenever the output is switched.

Voltage Controlled Crystal Oscillator (VCXO)

A Voltage Controlled Crystal Oscillator has its output frequency varied by means of an external control voltage. The most common application for VCXOs are in phase-locked loops, although other applications such as frequency shift keying in data transfer also require this function.

Temperature Compensated Crystal Oscillators (TCXO)

Temperature Compensated Crystal Oscillators have a highly stable frequency output over a wide operating temperature range. High stability is achieved by utilising a compensation network internally derived from measured frequency deviations during manufacture.

If you require any further information, please complete our simple contact form, or call us on Tel +44 (0)1460 230000or email and one of our engineers will be touch.

Latest News

Euroquartz Exhibit New Crystals and Oscillators.

Euroquartz are showing their latest Military spec oscillators and MEMS filters at the Embedded Design and Electronica Exhibitions Read more

Mil-Spec High Reliability Crystal Oscillators Launched.

Frequency control specialist, Euroquartz has launched two new ranges of military specification crystal oscillators designed for use in applications that require high reliability. Read more

New Low Profile Differential Output Oscillator Launched.

Euroquartz has launched a new low-profile, differential output crystal oscillator (DFXO) from Statek, designed for use in applications requiring low jitter and ultra-high frequency differential outputs in a small footprint. Read more

More News

Subscribe to our newsletter

Please enter your email address and you will receive the news direct into your inbox.



Euroquartz Accreditations

Partnership companies


Euroquartz are the specialist European supplier of Statek Inc.~ Unique designs, high-relieability crystals and oscillators, specialist manufacturer of components for use in extreme environments.


With Axtal GmbH products Euroquartz provides European-manufactured high quality oscillators, VCXOs, TCXOs and OCXOs, specifically applicable to tight tolerance and high reliability requirements.


Euroquartz supply the Greenray Inc. range of high-reliability oscillators, TCXOs, VCXOs and OCXOs. High-precision parts for exacting requirements.