Dual-Level LVDS Circuit with Common Mode Bias Compensation Technique for LCD Driver ICs

공통모드 전압 보정기능을 갖는 LCD 드라이버용 듀얼모드 LVDS 전송회로

  • 김두환 (충북대학교 정보통신공학과) ;
  • 김기선 (충북대학교 정보통신공학과) ;
  • 조경록 (충북대학교 정보통신공학과)
  • Published : 2006.03.01

Abstract

A dual-level low voltage differential signalling (DLVDS) circuit is proposed aiming at reducing transmission lines for a LCD driver IC. We apply two data to the proposed DLVDS circuit as inputs. Then, the transmitter converts two inputs to two kinds of fully differential signals. In this circuit, two transmission lines are sufficient to transfer two inputs while keeping the LVDS feature. However, the circuit has a common mode bias fluctuation due to difference of the input bias and the reference bias. We compensate the common mode bias fluctuation using a feedback circuit of the current source bias. The receiver recovers the original input data through a level decoding circuit. We fabricated the proposed circuit using $0.25{\mu}m$ CMOS technology. The simulation results of proposed circuit shows 1-Gbps/2-line data rate and 35mW power consumption at 2.5V supply voltage, respectively.

Keywords

LVDS;Low Power;Low Voltage;Differential Signal;I/O Circuit