m CMOS 5 V工艺的参数进行了仿真验证。在此像素电路中,当OLED发光时流过OLED的电流是恒定的,并且通过控制OLED的发光时间来实现不同的灰度。此像素电路完全由数字信号控制,能实现精确的灰度调节。通过6个子场,实现了21级灰度,进而论证了实现64级灰度(0~63)的可能性。当OLED发光时,流过的恒定电流是35.3 nA。
Abstract
In OLED-on-silicon micro-display
how to realize a small pixel driving current is the pixel circuit's difficulty. To solve this issue
a novel pixel circuit is presented in this paper. The pixel circuit is composed of two PMOS
two NMOS
one storage capacitor
one OLED and four signal lines. This circuit is verified by HSPICE basing on TSMC 0.35
m CMOS 5 V process. In this circuit
the current flowing through the OLED is constant when OLED is light-emitting and grayscale modulation is realized by controlling the OLED light-emitting time. This pixel circuit is fully controlled by digital signal and can achieve precise grayscale. In this paper
21 grayscale is achieved by six sub-frames. And then 64 grayscales (from 0 to 63) can be achieved by changing signals timing. When OLED is light-emitting
the constant current is 35.3 nA.
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references
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