How to choose the appropriate Epson crystal oscillator in different project applications
Release date:2018-10-15 Author:Guan Shuo Click:
Using quartz as raw material, thin slices are cut in accordance with a certain azimuth angle, and small devices are made into crystals, or crystal oscillators. The crystal oscillator is formed by adding IC inside the package. Crystal components have been widely used in various electronic devices, such as mobile phones, personal computers, printers, projectors, smart homes, smart watches, automotive electronics and so on. It can be said that almost all electronic products will use it, and it is also a very critical device. Crystal oscillators are like clocks and watches in electronic devices, giving CPUs time perception.
How do you choose crystal devices as an engineer? How is the most appropriate?
A good design and selection is a compulsory course for engineers. We all know that in the early stage of design, the choice of devices is very important, which directly affects the design quality and cycle of products. If you choose the right one, the less trouble you will encounter in designing the product, the lower the cost, and the faster the project progress. So today we're going to talk about how to choose the right crystal oscillator.
We are divided into several steps:
1. Choose crystal types according to their own applications
At present, many engineers are not particularly familiar with crystals. Crystals are classified into active crystals (crystal oscillators) and passive crystals (crystal oscillators).
The first step is to determine whether you are using source or passive.
What's the difference between passivity and activeness? Actually, it's very simple. Active power is a separate power supply port. Passive means that there is no separate power supply port.
A According to the application category
Consumer products, fast updating, low requirements, generally more passive crystals
Industrial products, update slowly, generally, most of them use ordinary active crystals, long-term stability is better.
Network products, long life, high application environment requirements, high communication quality, often use active crystals with functions, such as TCXO, V-TCXO, low jitter SPSO.
B According to the crystal requirements
For example, the product renewal rate is low, the phase noise is good, the frequency deviation in the whole temperature range is low, and the temperature requirement is high. Active crystals are needed. For example, Epson's ordinary active crystal SG series, SG-210STF, SG7050, temperature compensation crystal TG2520, TG-5006, or real-time clock module RTC.
For example, the product is updated quickly, the design cycle is short, the accuracy is not high, only the accuracy at room temperature is required, at this time passive crystals are generally chosen. For example, Epson FC-135, FA-12M, FA-238 and so on.
2. DETERMINATION OF CRYSTAL PARAMETERS
After determining the type of crystal selection, we further determine the parameters to be selected according to whether the crystal is passive or active. Passive crystals confirm the following parameters: frequency accuracy, load capacitance, operating temperature, size, frequency offset requirements in full temperature range.
3. Finally, communicate with the manufacturer and choose the best product with reasonable price.
Next:Characteristics and advantages of Epson crystal angular velocity sensor