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Abstract
We 英国留学生电子科技研究论文 developed a new custom-made high voltage driver with three voltage levels and with low power consumption for Quick-Response Liquid Powder Display (QR-LPD), which allows variety of driving method. The difference between the driving methods was investigated in terms of image quality and power consumption.

1.Introduction
Almost all the applications of electronic paper are required to have ultra low power consumption. For example, a price tag application requires the lifetime for several years without changing a battery. For a mobile application, there is no doubt that a low power device has much advantage because of freedom from the recharging a battery as well as the smaller battery size. To satisfy this demand the instability of a display is indispensable for an electronic paper application.

The instability of Quick-Response Liquid Powder Display (QRLPD®) [1, 2] is outstanding. The image on the panel can be retained for several years if no electrical shocks are applied. In this pointer-LPD® is thought to be an ideal electronic paper, but to drive the cell relatively high voltage is still needed at present (although the driving voltage is getting lower as the development is progressing) and the power consumption can be reduced efficiently by improving the driving circuit. To treat the high voltage leads disadvantage by itself in the viewpoints of a cost and power consumption. The high voltage transistor takes a large area in LSI and the even small leakage current results in high power consumption in a chip. On the other hand, a large and high-resolution electronic paper display needs a large number of connections to the driver LSI outputs. Assuming the letter size 200dpi electronic paper nearly 4,000outputs is needed, and the driver chip cost becomes dominant in module cost. Therefore, to develop the low cost and low power consumption driver LSI is important.
In this paper we will show some technologies used in the custom driver LSI for QR-LPD®, which realizes low power consumption using a new level shifter circuit and a good image quality applying the three-voltage-level output.

2. Custom Driver LSI
Figure 1 (a) is a whole picture of the developed driver LSI, which has a long shape with 2.3mm×21.4mm. Figure 1 (b) is a close-up picture, which shows that more than half area of the chip is taken by high voltage transistors. This driver has 160 outputs and three voltage levels, that is, high voltage (HV), the middle voltage (MV) and the grand voltage (God). The panel of QR-LPD® has a large capacitance, so the MV level should have a function sourcing the current to the load as well as sinking the current from the load, which enables to fasten the discharge from HV level and to recover the power from the panel. A conventional CMOSadding the 110 V DMOS process was employed. In this process the gate insulator cannot be applied more than 5V even for that of high voltage PMOS. Hence, an ordinal inverter circuit is not available and the bias circuit to generate the voltage for the HVPMOSgate gets complicated and consumes a large power.

References
[1] Reiji Hattori, Shushed Yamada, Yoshitomo Masuda, NorioNihei: “A novel bitable reflective display using quickresponseliquid powder” Journal of Society for Information Display, Vol.12, No.1, pp.75-80 (2004)
[2] Reiji Hattori, Shushed Yamada,本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。