A Mixed-Signal Driver Chip for 65K-Color Passive-Matrix OLED

Abstract

Organic light emitting display (OLED) is a new type of flat-panel display (FPD). And the research on the mix-signal driver chip for OLED is still going on. A single-chip passive-matrix OLED driver for 96 (RGB) X 64-pixel panel is presented in this paper. This driver chip has a 256-step contrast control and a 65k-color control. It consists of a digital controller, a SRAM as display data memory, a built-in DC-DC boost converter, an oscillator, 3 (RGB) reference current generators, 64 common drivers, and 96 X 3 segment drivers. The segment drivers use the pulse amplitude modulation (PAM) method to modulate grayscales and the voltage pre-charge technology to pre-charge the OLED pixels. This chip is a typical current-drive circuit. Simulation and analysis of its power consumption indicate that it is necessary for us to research the circuit design of the drivers and display mechanism (including pre-charge and discharge) further.