Sep 17, 2009

   NIHON DEMPA KOGYO CO., LTD. (President : Hiroshi Takeuchi) has developed and started to ship mass-produced compact high frequency range type VCXO (Voltage-Controlled Crystal Oscillators).

   Miniaturization of devices is required at high-speed wireless broadband networks and base stations for mobile communications from the perspective of establishing low-cost installations and operation. High frequency clock signals between 600 MHz to 700 MHz are required for the optical transmission devices and optical multiple-wavelength transmission devices used in these base stations and core networks.

   In order to meet the market requirements, NDK has developed the “NV7050SA” VCXO. It handles high frequency and has a small package, 7.0 × 5.0mm (one-tenth volume compared to the conventional products) while maintaining the same frequency stability and pull-ability range as the conventional products. Furthermore, ultralow phase jitter is achieved at a few tens of femtoseconds, which is an order of magnitude lower than previously developed products.

   PLL frequency multiplication is generally used to obtain high frequencies in the range of hundreds of MHz, however the drawback is phase jitter is magnified during this process which can significantly degrade the quality of transmission signals. Through NDK's proprietary technical knowledge, high frequency fundamental crystal units were designed and applied to obtain high frequencies without the need for PLL frequency multiplication processing. This has enabled the phase jitter to reduce to values of one quarter to one fifth the level of phase jitter produced by conventional PLL multiplication type VCXO [See Table 1].

[Model] NV7050SA	NV7050SA
[Sample]  available now. Sample price : JPY 3,000 to JPY 5,000.
[Main Specifications]
•  Dimensions : Typ. 7.0×5.0×1.6 (mm)
•  Nominal frequency range : 170 MHz to 700 MHz
•  Output voltage : +3.3V ±10%
•  Overall frequency tolerance : Max. ±50×10-6
•  APR (Absolute Pull Range*1) : Min. ±100×10-6
•  Operating temperature range : –40°C to +85°C
•  Output : LVPECL / LVDS
•  Phase Jitter (rms) :  Max. 100 fs (12 kHz to 20 MHz)  Max. 100 fs (50 kHz to 80 MHz)
•  Clock oscillator type is also available, please contact us for further details.

[Table 1] Phase jitter characteristics (conversion from Phase noise [See Figure 1])
  

[Figure 1] Phase noise characteristics
  

[Contact]
  NIHON DEMPA KOGYO CO., LTD.   Sales Representative
  TEL : 03-5453-6751   FAX : 03-5453-6756
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