Patent ID: 7518415
Filing Date: 2009-04-14
Classification: G09G,H03K

Abstract:
1. A voltage buffer, comprising: an operational amplifier, having a positive input terminal, a negative input terminal and an output terminal, wherein the output terminal is coupled to the negative input terminal and outputs an output voltage; and an overdriving unit, coupled between an input voltage and the operational amplifier for comparing the input voltage with the output voltage and outputting an overdriving voltage to the positive input terminal of the operational amplifier; wherein if the input voltage is greater than the output voltage, the overdriving unit makes the overdriving voltage greater than the input voltage; if the input voltage is less than the output voltage, the overdriving unit makes the overdriving voltage less than the input voltage; if the input voltage is equal to the output voltage, the overdriving voltage is equal to the input voltage.