Input/output circuit

Abstract

In some embodiments, an input / output (I / O) circuit sends and receives a high-level signal and a low-level signal via a coupling capacitance provided on a communication line. The I / O circuit includes a receiving portion including a first detection circuit arranged to detect one of the signals and a second detection circuit arranged to detect the other signal, a transmitting portion including a three-value output circuit configured to output one of signals consisting of a high-level signal, a low-level signal, and a high impedance signal, and a control circuit configured to control the receiving portion and the transmitting portion. The control circuit judges a level of an inputted signal depending on detection results of the first detection circuit and the second detection circuit in a receiving state and controls an output value of the three-value output circuit in a transmitting state.

Description

[0001]This application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2009-224992 filed on Sep. 29, 2009, the entire disclosure of which is incorporated herein by reference in its entirety.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]Some preferred embodiments of the present invention relate to an input / output circuit (I / O circuit), and, more specifically to a communication I / O interface capable of reducing power consumption.[0004]2. Description of the Related Art[0005]The following description sets forth the inventor's knowledge of related art and problems therein and should not be construed as an admission of knowledge in the prior art.[0006]In recent years, considering environments, electronic products are required to be operated at a low power consumption rate. In a capacity-coupled type communication device commonly used in a signal I / O circuit arranged between ICs mounted in an electronic product, the power consumption can be roughly...

AI Technical Summary

Benefits of technology

[0012]The preferred embodiments of the present invention have been developed in view of the above-mentioned and / or other problems in the related art. The preferred embodiments of the present invention can significantly improve upon existing methods and / or apparatuses.

[0013]Among other potential advantages, some embodiments can provide a signal I / O circuit low in power consumption or capable of minimizing power consumption.

Problems solved by technology

This constant electric flow flowing through the comparator causes a large amount of power consumption.

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