Development Trend of Epson Programmable Crystal Vibrator
Release date:2018-12-19 Author:Guan Shuo Click:
Development Trend of Epson Programmable Crystal Oscillator
1. Low power consumption, fast start-up, low voltage operation, low level drive and low current consumption have become a trend. Power supply voltage is generally 3.3V. For many TCXO and VCXO products, the current loss does not exceed 2mA. The rapid start-up technology of quartz crystal oscillator has also made breakthroughs. For example, VG-2320SC VCXO manufactured by Japanese Seiko has a frequency stabilization time of less than 4 ms under the specified value range of <0.1 ppm. SMDTCXO manufactured by Tokyo Ceramics Company of Japan can reach 90% of the rated value after starting the oscillation for 4ms. The OCXO products of OAK company with 10-25MHz can reach the stability of <0.01ppm after 5 minutes'preheating.
2. Low noise and high frequency are not allowed to cause frequency jitter in GPS communication system. Phase noise is an important parameter to characterize oscillator frequency jitter. The phase noise performance of OCXO mainstream products has been greatly improved. Except for VCXO, the maximum output frequency of other types of crystal oscillators does not exceed 200 MHz. For example, UCV4 series voltage controlled oscillators for mobile phones such as GSM have a frequency of 650-1700MHz, a power supply voltage of 2.2-3.3V and an operating current of 8-10mA.
3. High precision and high stability. The total accuracy of the uncompensated crystal oscillator can also reach (+25 ppm). The frequency stability of VCXO can generally reach (+20-100 ppm) in the range of 10-7 C, while the frequency stability of OCXO is (+0.0001-5 ppm) in the same temperature range. The VCXO is controlled below (+25 ppm).
4. Miniaturization, flaking and flaking: In order to meet the requirements of light, thin and short portable products represented by mobile phones, the packaging of quartz crystal oscillator has changed from traditional bare metal enclosure coated with plastic metal to ceramic encapsulation. For example, the volume of TCXO devices has been reduced by 30 to 100 times. The thickness of TCXO packaged with SMD is less than 2 mm. At present, devices with 5 *3 mm size have been put on the market.