Learn more from our Frequently Asked Questions
Yes; if the device that you are looking for is not a stock part then a programmable oscillator may be available, these are compatible with the fixed frequency device and can often be supplied in just a few working days. By comparison, a custom fixed frequency part may take up to 6 weeks in production. Programmable oscillators (or Fast-make Oscillators) particularly lend themselves to prototyping where time is critical. Despatch times are dependent on quantity; please contact us for further details.
The capacitance of the oscillator circuit is connected to the quartz crystal, whether in series or parallel configuration. The most common type of crystal is parallel resonant, where the crystal operates at a frequency above its series resonant frequency (the point of lowest impedance). The capacitance value is also crucial for determining the frequency tolerance. To learn more about this topic refer to our blog regarding: The common myths around load capacitance
Quartz crystals rely on the piezoelectric effect for their operation. This involves a quartz resonator connected with electrodes on both faces and mounted in a sealed holder. Applying an external AC voltage to these electrodes generates a mechanical vibration. To know more characteristics of Quartz crystal, refer to our Application Note.
The following specifications are required to be able to quote the correct part:
Yes! For example, if a crystal is specified over –10 to +60°C it will perform without any issue over –40 to +85°C but it is possible that it will fall outside its specified stability. This may not matter if the application needs just a stable frequency rather than an accurate frequency.
If the temperature goes significantly outside the specified temperature range it is possible that damage to the crystal may be caused. Also, refer above.
A fundamental crystal oscillates at a frequency determined by the dimensions of the quartz blank. Overtone crystals operate at the 3rd, 5th, or 7th multiple of the fundamental frequency. The crystal is specifically designed to operate in overtone mode, and enables higher frequencies to be achieved.
This depends upon the application. For example, if the crystal is pullable i.e. the frequency can be changed by varying the load capacitance of the crystal by electrical means, then this may be difficult to achieve. For example strip blank SMD crystals have a very much lower pullability than the HC49 style round blank package.
This exercise should not be undertaken lightly and if you are in any doubt, contact IQD's Applications Support department for further advice. Get in touch to get support from our Tech Experts.
This depends upon the application. If you are designing a discrete circuit and have little or no experience of oscillator design then it may be preferable to use a packaged oscillator since this will remove any tolerance issues. It is "easy" to design a "one off" for lab use but if you have to manufacture large numbers in volume this may give rise to a variety of issues. If you are using a chipset which requires a crystal to drive it then this decision is much simpler since the on board oscillator circuit should have been optimised.
SPXO - Simple Packaged Crystal Oscillator
An SPXO or a Simple Clock Oscillator is the most basic type of oscillator and consists of a crystal and a basic drive circuit. Since there is no form of compensation the frequency/ temperature stability is essentially that of the crystal itself – typically ±50ppm. For more information, check out our Application Note.
VCXO - Voltage Controlled Crystal Oscillator
A VCXO relies on the inherent pullability of the quartz crystal to allow the output frequency of the oscillator to be changed by applying an external voltage. This change is limited to a few tens of ppm, typically ±100ppm. As with SPXO's, the frequency/ temperature stability is that of the crystal itself. For more information, check out our Application Note.
TCXO - Temperature Compensated Crystal Oscillators
Where the stability of the crystal is not sufficient it may be necessary to use a TCXO. This type of device is used where the stability of a basic quartz crystal is insufficient. Typically, TCXO's can achieve a stability of less than ±1ppm in preference to a typical crystal of 30ppm. For more information, check out our Application Note.
OCXO - Oven Controlled Crystal Oscillators
The "ultimate" piezoelectric product is the OCXO, it offers performances of typically 3E10-9. In applications where high stability is required then this type of product should be considered. For more information, check out our Application Note.
Disciplined OCXOs
They are essentially OCXOs with additional capability for precise timing synchronization down to 1 pulse per second (1pps). This clock module is exceptionally accurate as it is synchronized with GNSS signals. DOCXOs play a crucial role in environments where regular signal outages should not disrupt the intended application. For more information, check out our Application Note.
Rubidium XOs
Rubidium oscillators are atomic clock modules that are preferred for their long-term stability. They also have an OCXO along with a physics-package at the centre of their circuitry and the change in the energy levels in the rubidium gas chamber generates the desired o/p frequency. For more information, check out our Application Note.
To review our parts and their respective specifications, you can visit our Parametric Search page. If you need additional information, please visit our Contact page.
Our technical team is experienced and among the best in the industry, capable of providing you with information regarding our extensive catalog of frequency products. We also offer additional technical support for your designs, including custom product development, testing and more.
Call us directly at +44 (0) 1460 270 200, or check out our dedicated page Engineering Support Services for more details on technical support or visit our Contact page.
If a product has become obsolete or is reaching its end of life, our Applications Support team will be happy to advise you with a suitable alternative product. Please contact us at +44 (0) 1460 270 200 or email us at info@IQDfrequencyproducts.com.
The answer is yes. Please look under the Distributors page. Find the link here: Distributors.
Yes; our engineering department is constantly developing our product range and indeed much of its capability is in customisation. If you have a requirement for a custom product or looking for a specific competitor’s part, our team will be delighted to assist and advise you. You can get in touch with us here.
Miniaturisation is an ongoing trend in the electronics industry. Wearables, smart home devices, mobile devices and electronics in automotive applications are just a few examples demanding progressively smaller components. However, this size reduction can cause issues during the designing process – in general, the smaller the crystal blank, the higher the starting frequency.
For example, the lowest frequency in a 7x5mm package is approximately 6MHz, whereas it is approximately12MHz in a 2.5x2mm package. Achieving lower frequencies in smaller packages is done through external frequency division, which, in turn, increases circuit complexity. To get more idea on miniaturisation and its effects in designing, visit Design effect of crystal downsizing blog post.
All sample orders are dispatched with the appropriate test result data. Production order quantities are tested to the Appropriate Quality Level (AQL), and the test result data is retained in our company records. For further information, please contact us.
AT-cut quartz accounts for the majority of crystals produced in the 1 to 200MHz range. This term simply refers to the nominal angle with respect to the Z-axis of the quartz bar. The cut angle determines the frequency/temperature performance and is typically chosen by the crystal manufacturer.
For more information about any of our parts or for help with your design-in, you can contact our Sales Team, Application Support or Engineering on +44 (0) 1460 270200, or click Contact Us below to submit your enquiry.
