Input buffers with both pull-up, pull-down, and normal functions

摘要

The present invention relates to an input buffer having both pull-up, pull-down, and normal functions. According to another aspect of the present invention, there is provided an input buffer comprising: a pad to which an input signal is applied; buffer means connected to an input terminal of the pad for buffering a signal applied to the pad; Up means for pulling up the input of said buffer means in response to a pull-up control signal; a pull-down means connected in a predetermined position of a connection line between said pad and said buffer means, And a logic means for generating the pull-up control signal and the pull-down control signal by inputting a predetermined enable signal and a predetermined selection signal. Therefore, the input buffer having both pull-up, pull-down, and normal functions according to the present invention has an advantage that the function can be selectively implemented according to the purpose of the designer.