38.1: A Novel 2‐Stage Analog Amplifier with Self‐Compensated Current Loads using Low Temperature Poly‐Si (LTPS) TFTs for Flat Panel Displays

Abstract

A novel 2‐stage analog amplifier with self‐compensated p‐type current loads for LTPS TFT‐LCDs is proposed. The proposed 2‐stage analog buffer has three phases for compensation. The first and second compensation phases are self‐compensation for the p‐type TFT active loads and third compensation phase is typical auto‐zeroing compensation for a 2‐stage buffer. This method can suppress the offset voltage generated by the mismatch of the current loads and input differential pair. We fabricated the proposed buffer using LTPS TFTs and measured its electrical characteristics. The measured maximum offset voltage is 10mV for the full output voltage to range.