TOSHIKATSU MAKUTA, CHISATO ISHIMARU, MASANOBU OKAZAKI
NIHON DEMPA KOGYO CO.,LTD.
1275-2, KAMIHIROSE, SAYAMA CITY, SAITAMA 350-1321, JAPAN
Tel:+81-4-2955-6319 Fax:+81-4-2953-2884
E-mail:
ABSTRACT
The processing technology of IC (Facedown bonding) is effective to making the IC a low height. By using of Facedown bonding technique, we could to develop the ultra slim crystal oscillator as 5 x 3.2 x 1.0mm size. Furthermore by using of the PLL technology, the output frequency can be realized 1-125MHz range.
1. INTRODUCTION
Crystal Oscillators (XO) that are used for personal computer, electric toys and so on show its drastic advancement in term of high frequency and package miniaturization. For example, available frequencies used to be mainly for clock timing purpose and the maximum frequency was 40MHz in early 1980. However, it is not only for the purpose, but also new applications like portable audio / visual equipment are using crystal oscillators recently. Higher frequency than 100MHz is available now. On the other hand, as showing Fig.1, the package size used to be about 13 x 13 x 5mm, but it has been advanced to about 5 x 3.2 x 1.0mm in these days. And Fig.2 shows the out line of 5 x 3.2 x 1.0mm size oscillator.
Therefore, the necessity corresponding to a high frequency is caused by miniaturize being aimed at by using the IC chip and the processing technology in these oscillators and using the technology of PLL. Since miniaturization of oscillator drives the one of crystal units, it is necessary to reinforce the spurious response control of crystal units and to stabilize oscillation frequency.
In this paper, firstly the characteristic of oscillator which uses processing technology (Facedown bonding) of IC is described and the examination result of the frequency temperature characteristic of crystal units is introduced. Next, as an example of execution, We would like to introduce you the design specification which is required for 5.0 x 3.2 x 1.0mm size 27.000MHz clock oscillator used for portable audio / visual equipment. The selection of the size at the crystal blank and the configuration of the electrode are described. In addition, the configuration of an active side where the IC technology was used and the frequency stability of the entire oscillators are described. Then, our anticipation the progress of the technology used with this oscillator in the future is introduced to the end of the paper.
Fig.1 Development road map of clock oscillator
Fig.2 5x3.2.x1.0mm Oscillator Out line