Overdrive amplifier and semiconductor device

Abstract

The present invention relates to an overdrive amplifier and a semiconductor device. An overdrive amplifier that satisfies both low current consumption and high-speed drive can be realized by adding a small-scale circuit. The overdrive amplifier has: a differential input circuit (100) having an input transistor (MP12, MN12) supplying an input signal to a gate and a feedback input transistor (MP11, MN11) feeding back an output signal to the gate as a pair of differential input transistors a current mirror load (101) with a mirrored input current path connected to the current path of the feedback input transistor and a mirrored output current path connected to the current path of the input transistor; input and output from the mirrored output current path of the current mirror load an output circuit (102) of a control signal; and a bias current (Ip, In) that enhances a direction of an output of the output circuit using the output control signal during overdrive to flow through the An overdrive circuit (103) for a current mirror load.

Description

technical field [0001] The present invention relates to an overdrive amplifier, and further relates to a semiconductor device including the overdrive amplifier, and relates to effective technology applied to an LCD (liquid crystal display) driver IC (Integrated Circuit, for example). Background technique [0002] The drive performance of a load driven by a buffer amplifier or the like differs between the near end and the far end of the load, and also differs depending on the temperature of the load. For example, in a liquid crystal display panel, a plurality of liquid crystal display elements are arranged in a matrix in the row and column directions, the gate lines are connected to the selection terminals of the liquid crystal display elements in units of display rows in the row direction, and the source lines are connected in units of column directions. It is used as the data terminal of the liquid crystal display element. A plurality of source lines are driven by a drivin...

AI Technical Summary

Problems solved by technology

The resistance component and the capacitance component of the liquid crystal display element are distributed in the source line, and the load component of the remote end becomes larger. Even if the drive amplifier is operated at high speed, the convergence time at the near end of the load is short. There is also a difference in the convergence time of the remote end of the load, and the convergence time of the remote end tends to be delayed

When the panel load is large, the RC of the panel load dominates the convergence time at the far end of the load, and even if the drive amplifier is increased in speed, it is difficult to increase the speed of the drive amplifier.

[0003] The difference in the drive convergence time between the near end and the far end of the load is noticeable depending on the size of the liquid crystal display panel, the size of the allowable power consumption, etc., and the difference may also occur in a low temperature environment

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