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A Closer Look at Quartz Crystal Components

What is crystal device?

What is crystal device?

Because crystal devices such as quartz crystal units and quartz crystal oscillators have high stability against an environment change such as temperature, they are used as frequency control devices in electronic circuits. From smartphones, digital still cameras, automobiles, medical devices, to Ubiquitous Network, the product category for crystal devices are becoming wider.

“Mystical” Quartz Crystals?Surprisingly Practical

Of precious stones, crystals are relatively familiar. They are used in traditional crafts, jewelry, and even mystical crystal balls. But quartz crystals are also key objects in modern lifestyles, where they fulfill a vital role in smartphones and other mobile phones, digital cameras, and automotive electronics.

Discovery of a Key Effect

Composed of silicon dioxide, these clear, colorless crystals are piezoelectric, generating a voltage when their structures are deformed. Subjecting quartz crystals to mechanical stresses generates a charge across the surface, a phenomenon known as the piezoelectric effect (illustrated at left below). This effect is reversible; applying a voltage can deform crystals (illustrated at right below). Discovered more than a century ago by French physicists Pierre and Jacques Curie, this effect is harnessed by quartz crystal components.

機械的な圧力を加えると水晶は電気を発生します

Characteristics of Quartz Crystal Components

Applying an electric field to crystal wafers cut at specific angles causes them to oscillate at constant frequencies. Due to their purity, quartz crystals continue to generate very stable oscillation frequencies. Electric signals derived from these frequencies are used in electric circuits of many kinds. Quartz crystal components are extremely stable at various temperatures and other environmental conditions. For this reason, they are used in electronics that must operate at precise frequencies. Without accurate computers, smartphones, or navigation systems, life as we know it would certainly be different. We enjoy the benefits of quartz crystal oscillation without knowing it.

Roles of Quartz Crystal Components

Although the roles fulfilled by quartz crystal components may vary by component, all are critical. It is no exaggeration to say their use in electronics is all but universal. Here, we describe quartz crystal units and oscillators, as manufactured by RIVER ELETEC, which primarily fulfill the following two roles in electronics:

Maintaining stable frequencies

Producing steady reference signals

The first role?maintaining stable frequencies?is essential for radios, televisions, mobile phones, and other devices that rely on wireless signals. These products cannot send or receive information unless they operate at the specific designed frequency. For example, the radio frequency spectrum is subdivided into precise frequency bands assigned to mobile phones to allow many people to communicate with base stations in the same area at the same time. If phones operate at the wrong frequencies, crosstalk and interference result, preventing communication. Quartz crystal units and oscillators oscillate at constant frequencies, providing a reference signal for stable device operation at specific frequencies. This enables devices to send and receive signals at the frequency they were designed for.

The second role is to produce steady reference signals. Most electronic systems consist of multiple parts. Computers comprise hard disks, internal memory, optical drives, and other peripheral circuitry, as well as a CPU. Although forming a single system, these systems serve different purposes. Unless the timing of their operation is coordinated efficiently, the system as a whole will not function as designed. This timing requires a steady clock signal. Quartz crystal units and oscillators produce this signal, acting in a sense in the same way a conductor directs a symphony orchestra.

Roles of quartz crystal units and oscillators can be further summarized as follows:

role and use

Unexpected Prevalence of Quartz Crystal Components

As a core part in electronics, quartz crystal components are used across a wide range of products. On average, a single digital camera incorporates three quartz crystal components. And as electronics gain more features or more advanced features, they are likely to use more quartz crystal components. The market for quartz crystal components is all but certain to continue expanding.

market

Quartz Crystal Components from RIVER ELETEC

These components can be broadly classified into five types: quartz crystal units, quartz crystal oscillators, quartz crystal filters, SAW devices, and optical devices. Of these, RIVER ELETEC production focuses on two types---quartz crystal units and oscillators. Our specialty is surface-mount devices (SMDs).

Many Applications of Quartz crystal units and oscillators

Quartz crystal units fulfill the two roles mentioned: maintaining stable frequencies and generating steady clock signals. Additionally, they offer various oscillation modes, depending on how the wafer is cut and where electrodes are attached. AT-cut and tuning fork quartz crystal units are the best known. These types of quartz crystal components are probably the most familiar, because their frequency and temperature characteristics make them more versatile. Quartz crystal oscillators incorporate oscillation circuitry in the quartz crystal unit, in the form of an integrated circuit. Various subtypes are available, such as temperature-compensating and voltage-controlled. RIVER ELETEC focuses on the general-purpose quartz crystal oscillators used across a wide array of electronics.

RIVER Technology

The evidence of RIVER ELETEC technology is “sealing method by electron beam.” With this most advanced technology, we have successfully developed the quartz crystal unit in world’s smallest class, FCX-07. Further, such technologies as a design of crystal elements, fine processing skills, and high accuracy loading skills on containers are matured as technologies which create small-sized, high performance crystal devices.

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