circuit board with oscillator

Grow Your Foundational Knowledge Of Crystals and Crystal Oscillators

Today’s digital circuits must ensure that critical processes, both internal and external, occur as planned. Digital circuits operate at extremely high speeds and require exceptional components, including crystals and oscillators, to facilitate communication, the orchestration and synchronization of processes and information storage.

These components are known as frequency control products. They control the accuracy and stability of a digital device’s most essential tasks. You can think of frequency control products as the “heartbeat” of a circuit: a steady, dependable pulse that ensures tasks go as planned.

Why Are Crystal Oscillators Used In Electronics?

Frequency control solutions, also called timing solutions, are one of the most common electronic components. They are also one of the most essential. Today, all digital circuits need clocks to switch them from high to low or on to off. Processors perform these operations at high speeds and need crystals or oscillators to start them up.

For electronics that keep “human time,” such as the time display on your appliances, designers use kHz crystals and crystal oscillators. Spurred by the invention of the digital watch in the 1970s, crystals are the most common choice for electronics. If you divide 32.768kHz by two 15 times, you achieve 1hz. 1hz is equivalent to 1 second. Oscillators can also emit radio frequency (RF) signals that are multiplied to meet mobile phone frequency requirements, such as 2100 MHz.

Further reading: Learn more about the history of using quartz in electronics.

Common Frequency Control Products

Timing solution manufacturers most typically build the following products for use in modern applications.

  • Crystals: These are the most common devices used for most processors. They are available in kHz (watch crystals) and MHz versions. Crystals need matching caps on the printed circuit board (PCB) to make the oscillator loop.
  • Crystal oscillators: Often abbreviated as XOs, crystal oscillators are used to clock processors or other digital circuits. Sometimes engineers use them to simplify designs, as no matching is needed.
  • Voltage-controlled crystal oscillators: Voltage-controlled crystal oscillators are used in RF processors or circuits where a variable frequency is needed, such as in professional RF equipment.
  • Temperature-compensated crystal oscillators: Like VCXOs, TCXOs are used in RF devices like mobile phones or GPS to stabilize the frequency. These products can alter their frequency to safeguard against the effects of temperature.
  • Oven-controlled crystal oscillators: OCXOs are larger devices used to clock master controller boards, like mobile phone base stations or electronic test equipment. Their internal heaters regulate temperature to maintain a high performance.
  • MultiVolt oscillators: These devices fit into many oscillator sockets and cover a broad range of supply voltages. Multivolts are modern ASIC driven oscillators with improvements in performance and function.
  • Programmable oscillators: Programmable devices like ECSpressCON are configurable clock oscillators. They are available as XOs, VCXOs or TCXOs. These products are used where standard frequencies do not exist or require a much higher frequency.
  • AEC-Q200-rated oscillators: The Automotive Electronic Council develops international standards for the automotive industry to ensure that products used in vehicles are highly reliable. These products are typically crystals, XOs or TCXOs.

Further Reading: For a deeper dive, read this technical introduction to frequency control.

What to Know About MEMs Oscillators

Microelectromechanical oscillators (MEMs) are often touted as a competitor to crystal oscillators. However, the benefits of MEMs are particularly niche and, in some cases, irrelevant for most designers.

MEMs deliver improved performance for a longer period of time than crystal oscillators, but this difference in performance takes place at a point beyond the useful life of the application.

MEMs oscillators are also marketed as a durable frequency-control solution, but their level of ruggedization is only necessary under exceptionally harsh and uncommon conditions.

Further reading: For a technical overview of MEMs, explore this white paper, comparing MEMs oscillators to quartz oscillators.

Frequency Control Market Trends

Digital electronics have gotten smaller and more widespread, which understandably affects which frequency control products are in demand.

  • The most common frequency control products: Globally, the most common crystal package is 3.2 x 2.5 mm.
  • Crystal size: 32.768 kHz watch crystals are getting smaller as well. Six years ago, the most common size was 8.0 x 3.8 mm. The 3.2 x 1.5 mm package size now supersedes it.
  • Oscillator size: Over the last five years, the desire for small package sizes has led to demand for oscillators as small as 2.0 x 1.6 mm.
  • The challenges of a smaller form factor: Smaller packages mean smaller crystals are used inside. This size reduction makes these components harder to start up when it is cold. However, crystal oscillator manufacturers have innovated solutions to cut crystals for these components.

Explore These Frequency Control Resources

The timing solutions market will continue to evolve, as the laws of accelerating change allow our technologies to grow exponentially. Stay updated on frequency control innovations by exploring this series of articles.

In particular, these articles from ECS Inc. provide industry-specific overviews that explain how today’s most critical markets use timing:

Your Helpful Guide to Frequency Control Products was last modified: January 27th, 2025 by ECS Inc.