ANALOG BUFFER CIRCUIT, DISPLAY, AND PORTABLE TERMINAL

摘要

PROBLEM TO BE SOLVED: To solve problems of an increased input and output offset in an analog buffer circuit and its increased variation in forming the analog buffer circuit by using a TFT (Thin Film Transistor) on an insulating substrate. SOLUTION: Two capacitors Cn1, Cn2, for example, are connected to the gate of an NMOS transistor Qn11 in a source follower. Control for the continuity and discontinuity of switches Sn1-Sn5 is appropriately done to perform the two-divided offset detection of the source follower. The detected offsets are successively canceled to sufficiently reduce the final offset voltage to materialize highly accurate offset cancellation. COPYRIGHT: (C)2004,JPO