2021.11.01 - Crystal Oscillator Frequency Ranges and Works

Crystal Oscillator Frequency Ranges and Works

Crystal oscillators are a pivotal component in electronics, offering stability, precision, and consistency. This blog post explains crystal oscillator frequency ranges, focusing on quartz oscillators and how they work.

What is a Crystal in Electronics?

A crystal oscillator is an electronic circuit that uses a vibrating crystal. It creates a precise electrical signal. The signal has a specific frequency.

People commonly use this frequency for various purposes. One of its uses is in measuring time, particularly in wristwatches with quartz. It provides a steady clock signal for digital circuits. Additionally, radios use it to stabilize frequencies.

How Does a Quartz Oscillator Work?

A quartz oscillator works on the principle of piezoelectricity. When you apply pressure to a quartz crystal, it generates an electric charge. The quartz crystal vibrates steadily when using an electric field, making it useful for measuring time. This is the basis of the quartz frequency standard.

The pierce crystal oscillator theory and design is the foundation of quartz oscillators. The design includes two metal plates and an ordinary quartz crystal.

When the metal plates get electricity, they make the quartz crystal shake at its own speed. Counters and other instruments can accurately measure this consistent signal.

Many modern electronic devices use Pierce oscillator circuit design. Pierce crystal oscillator design is highly accurate. Various industries, such as telecommunications, satellite navigation, and medical equipment, use it.

Quartz crystal oscillators also generate frequencies for radio broadcasting. Digital clocks and watches also employ them as a time base. Microcontroller chips often incorporate oscillators to control the timing of different operations in embedded systems.

Quartz oscillators are reliable and accurate for various applications, including communication, navigation systems, medical equipment, and other control systems. The quartz crystal is stable enough to provide frequencies over millions of cycles with minimal loss. You can easily adjust a quartz oscillator using laser trimming or voltage-controlled tuning techniques.

Understanding Crystal Oscillator Circuits

A crystal oscillator circuit, like the Pierce design, uses a crystal with resistors, capacitors, and transistors. The crystal stabilizes the oscillator's frequency by resonating and creating a feedback loop with other parts.

How Does a Crystal Oscillator Circuit Work?

The crystal oscillator circuit works by generating a periodic signal. The device amplifies the signal and then sends it to the output pins. The feedback loop occurs when the input receives some of this output and feeds it back. This allows for greater accuracy and stability in frequency generation, which makes it useful for radios.

The mechanical vibrating or mechanical resonance of the crystal creates the periodic signal. You can do this in two ways: by using a quartz crystal or an LC tank circuit. In a quartz oscillator, the quartz crystal vibrates at a certain frequency due to its shape and size. The crystal's vibration creates an electric field that makes electrons move back and forth around it.

Crystal Oscillator Circuit Design Schematic

A crystal oscillator circuit design schematic includes the following components: a crystal, transistor, resistor, and capacitor. The crystal is what creates the feedback loop by resonating with other members. The transistor boosts the signal to make the output, while the resistor and capacitor adjust the oscillation frequency.

Loop gain measures how much the input signal is amplified before outputting, and changing it affects the circuit's performance.

Frequency Range of Crystal Oscillators

Crystal oscillators can have different frequencies, ranging from a few kHz to hundreds of MHz. The most common frequency for a quartz crystal oscillator is 32.768 kHz, used in many applications like real-time clocks. Contact Harmony for a chart of crystal frequencies or more info on the crystal oscillator circuit pdf and schematics. 32.768 khz crystal oscillator circuits are key in many timing and switching applications.

Frequency controlling with desired frequency is crucial in crystal oscillator circuits. Many methods of frequency control exist, such as adjustment of capacitance, inductance and resistance of the circuit elements, frequency modulation, temperature compensation, etc. Every method has pros and cons, so consider them when using frequency control. Accurate frequencies are necessary for efficient operation.

Stable frequencies are also necessary to ensure the crystal oscillator circuit works as expected. When using an external frequency source, additional considerations include the temperature range and frequency accuracy of the device. Quartz crystals are precise at various temperatures but can be pricier than alternative sources.

You can change the frequency of an oscillator by adjusting the voltage, capacitance, or inductance of a circuit element. Frequency-determining elements must be stable and precisely adjusted to ensure accuracy. Frequency modulation is another method used to change the frequency of an oscillator.

Other methods are available. One method involves using a device that splits a signal into multiple signals with lower frequencies. Another method involves adjusting the timing of a waveform to make two waves of the same frequency out of sync. Digital systems can split a signal into multiple lower-frequency signals using counters or dividers.

Frequency Controlling Parameters

The resistor and capacitor are the two frequency-controlling components. The type of crystal used in the oscillator is also an important factor. When creating a circuit, it's crucial to think about load capacitance, ESR, and crystal aging for precise frequency stability. The applied voltage can also have a major effect on oscillation frequency.

Operating Frequency

To build a device, one must understand how to generate and control a signal frequency. Different circuits have different operating frequencies and bandwidths. Setting up the correct control parameters for your process is also essential. A timer, voltage-controlled oscillator (VCO), or counter/divider circuit can determine the output signal frequency.

When determining the optimal frequency for your crystal oscillator, consider various factors. Factors affecting it are how often it works, the temperature it faces, its size, cost, and reliability. Even 32.768 khz crystal oscillator datasheets are available.

Our Harmony engineering team and technical support can assist you in finding what you require. Contact us today!

Real-Time Clock Crystal Frequency

RTC Crystal frequency is a measure of the frequency of the crystal used in a real-time clock. The most common RTC Crystal frequencies are 32kHz, 4MHz, and 8MHz.

Different frequencies have advantages and disadvantages. These include accuracy, power usage, cost, and more.

People commonly use RC Crystal frequencies for alarms, timers, and other time-measurement purposes. They provide accurate time measurements.

Resonant Frequencies

The exact resonant frequency of the crystal used depends on its design and size. The number of electrodes present, the specific thickness of the material, and more determine this. Sometimes, certain things like remote control, satellite navigation, and wireless communication need higher frequencies.

The frequency of oscillations of a resonant circuit will depend on the size and shape of the crystal. The frequency chosen depends on its intended use. For example, watch crystals use 20-32kHz, oscillators use 4MHz, and microprocessors use 8-16MHz.

Crystal Oscillator Accuracy

A crystal oscillator's accuracy depends on how much it differs from the expected frequency in certain conditions. Typically, we specify the accuracy of a quartz crystal in parts per million (ppm) or hertz (Hz). Crystal oscillator circuit schematics are available. Crystal frequency charts are also available.

Crystal Oscillator Advantages

Crystal oscillators have numerous applications, from consumer electronics to telecommunications and aerospace applications. People prize them for their stability, accuracy, and reliability. The crystal oscillator application note provides more detailed information on this.

Some key advantages of crystal oscillators include their excellent frequency stability and low phase noise. They make precise and steady frequencies, perfect for timing devices like clocks and watches.

CMOS crystal oscillator technology is also popular for its low power consumption and cost efficiency. With this technology, designers can create a high-temperature oscillator for use in extreme environmental conditions, such as those found in automotive, defense, and space applications.

Other precision timing crystal manufacturers leverage many other types of oscillators, including quartz crystal, AT-cut Crystal Oscillator, MEMS oscillators, and surface acoustic wave (SAW) oscillators.

In Conclusion

Understanding how a crystal oscillator works, its circuit design, and its frequency range can help you decide which type is best for your specific needs. Harmony Electronics can help you with RTC, RC, or 32kHz crystal oscillator frequencies.

For more information about crystal oscillators, download our crystal oscillators pdf. We look forward to your positive feedback in helping you navigate the fascinating world of crystal oscillators and their myriad applications.





- 意林行銷 -