Patent ID: 8487921
Filing Date: 2013-07-16
Classification: G09G

Abstract:
1. A display panel driver comprising: an output amplifier circuit; a first output terminal; and a second output terminal, wherein said output amplifier circuit comprises: a first output stage configured to receive a power supply voltage and a first voltage lower than said power supply voltage and to output a drive voltage in a first voltage range defined between said power supply voltage and a middle power supply voltage which is higher than a ground voltage and is lower than said power supply voltage; and a second output stage configured to receive said power supply voltage and the ground voltage and to output a drive voltage between said power supply voltage and said ground voltage, wherein said first output stage comprises a first pull-down output transistor configured to pull down an output terminal of said first output stage, wherein said second output stage comprises a second pull-down output transistor configured to pull down an output terminal of said second output stage, wherein said first pull-down output transistor is a depletion-type NMOS transistor, wherein said second pull-down output transistor is an enhancement-type NMOS transistor, wherein when said output amplifier circuit is set to a first mode that said first voltage is set as said middle power supply voltage, said first output stage outputs a first drive voltage in said first voltage range to one of said first output terminal and said second output terminal, and wherein when said output amplifier circuit is set to a second mode that said first voltage is set as said ground voltage, said second output stage outputs a first drive voltage in said first voltage range to one of said first output terminal and said second output terminal.